Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mec...Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process.展开更多
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre...To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.展开更多
In the field of advanced oxidation processes(AOPs) of wastewater, many materials can be used as heterogeneous catalysts. The role of these catalysts is to activate oxidants and generate reactive oxygen species(ROS) to...In the field of advanced oxidation processes(AOPs) of wastewater, many materials can be used as heterogeneous catalysts. The role of these catalysts is to activate oxidants and generate reactive oxygen species(ROS) to decompose refractory pollutants. Perovskite oxide, an emerging catalyst in the field of AOPs, has been extensively studied in wastewater treatment. Nevertheless, the application of perovskite in AOP systems still faces some problems, such as leaching of metal ions, a small surface area, a low number of active sites, etc. Herein, this critical review comparatively examines the activation mechanisms of peroxymonosulfate, hydrogen peroxide, and peroxydisulfate. Furthermore, the formation pathways of oxidizing species based on recent advances in experimental and theoretical studies were evaluated. In addition, the impacts of water parameters and constituents such as initial p H, oxidant concentration, catalyst dosage,natural organic matter, halide, phosphate, and carbonate were discussed. Finally, a critical discussion and prospects of mechanism exploration and possible materials development are proposed to confront the existing challenges in the application of perovskite oxides in AOPs.展开更多
Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the el...Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.展开更多
The electrocatalytic urea oxidation reaction(UOR)has emerged as an energy-efficient alternative to the traditional oxygen evolution reaction for hydrogen production,with mechanistic understanding being critical for th...The electrocatalytic urea oxidation reaction(UOR)has emerged as an energy-efficient alternative to the traditional oxygen evolution reaction for hydrogen production,with mechanistic understanding being critical for the rational design of catalysts.This review systematically summarizes recent advances in in situ characterization techniques for elucidating the dynamic reaction mechanisms of UOR.Studies reveal that phase transitions,valence state migration,and electronic structure evolution of catalysts under operational conditions are key factors governing activity and stability.Techniques such as in situ X-ray diffraction,X-ray absorption spectroscopy,Raman spectroscopy,and Fourier-transform infrared spectroscopy enable real-time monitoring of catalyst reconstruction,intermediate evolution,and interfacial adsorption behavior,overcoming the environmental deviations inherent in conventional ex situ characterization.When combined with theoretical calculations,these methods provide direct evidence for identifying active-site configurations,reaction pathways,and rate-determining steps.In addition,special emphasis is placed on multimodal in situ strategies for deciphering synergistic effects in nickel-based catalysts,while current challenges,including non-alkaline systems,real wastewater environments,and multi-metal cooperation mechanisms,are critically discussed.Future research should focus on developing novel in situ approaches for complex systems and establishing a mutually reinforcing framework integrating theoretical prediction and experimental validation,thereby advancing UOR catalyst design from empirical exploration to mechanism-guided optimization.展开更多
Low-valent sulfur oxy-acid salts(LVSOs)represent a category of oxygen-containing salts characterized by their potent reducing capabilities.Notably,sulfite,dithionite,and thiosulfate are prevalent reducing agents that ...Low-valent sulfur oxy-acid salts(LVSOs)represent a category of oxygen-containing salts characterized by their potent reducing capabilities.Notably,sulfite,dithionite,and thiosulfate are prevalent reducing agents that are readily available,cost-effective,and exhibit minimal ecological toxicity.These LVSOs have the ability to generate or promote the generation of strong oxidants or reductants,which makes them widely used in advanced oxidation processes(AOPs)and advanced reduction processes(ARPs).This article provides a comprehensive review of the recent advancements in AOPs and ARPs involving LVSOs,alongside an examination of the fundamental principles governing the generation of active species within these processes.LVSOs fulfill three primary functions in AOPs:Serving as sources of reactive oxygen species(ROS),auxiliary agents,and activators.Particular attention is devoted to elucidating the reaction mechanisms through which LVSOs,in conjunction with metal ions,metal oxides,ultraviolet light(UV),and ozone,produce potent oxidizing agents in both homogeneous and heterogeneous systems.Regarding ARPs,this review delineates the mechanisms by which LVSOs generate strong reducing agents,including hydrated electrons,hydrogen radicals,and sulfite radicals,under UV irradiation,while also exploring the interactions between these reductants and pollutants.The review identifies existing gaps within the current framework and proposes future research avenues to address these challenges.展开更多
The employment of single atom catalysts(SACs)remarkably increases atomic utilization and catalytic efficiency in various electrochemical processes,especially when coupled with metal clusters/nanoparticles.However,the ...The employment of single atom catalysts(SACs)remarkably increases atomic utilization and catalytic efficiency in various electrochemical processes,especially when coupled with metal clusters/nanoparticles.However,the synergistic effects mainly focus on the energetics of key intermediates during the electrocatalysis,while the properties of electrode surface and electric-double-layer(EDL)structure are largely overlooked.Herein,we report the synthesis of Ru nanoparticles integrated with neighboring Ru single atoms on nitrogen doped carbon(Ru1,n/NC)as efficient catalysts toward hydrogen oxidation reaction(HOR)under alkaline electrolytes.Electrochemical data,in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy,and density functional theory calculations reveal that the positively charged Ru single atoms could lead to the dynamically regulated proportion of strongly hydrogen-bonded interfacial water structure with O-down conformation and optimized connectivity of the hydrogen-bond network in the EDL region,which contribute to the accelerated diffusion of hydroxide ions to the electrified interfaces.Consequently,the obtained Ru1,n/NC catalyst displays remarkable HOR performance with the mass activity of 1.15 mAμgPGM^(-1) under alkaline electrolyte.This work demonstrates the promise of single atoms for interfacial water environment adjustment and mass transfer process modulation,providing new insights into rational design of highly-effective SAC-based electrocatalysts.展开更多
Hexafluoropropylene oxide(HFPO)is a crucial fluorinated chemical mainly synthesized from hexafluoropropylene(HFP)through the oxidation of oxygen.However,the reaction network and kinetic characteristics are not fully u...Hexafluoropropylene oxide(HFPO)is a crucial fluorinated chemical mainly synthesized from hexafluoropropylene(HFP)through the oxidation of oxygen.However,the reaction network and kinetic characteristics are not fully understood yet,resulting in a lack of theoretical basis for synthesis process improvement.Here,the free radical reaction mechanism and complete reaction network involved in the noncatalytic oxidation of HFP to synthesize HFPO was explored by density functional theory.Transition state theory was employed to calculate the intrinsic reaction rate constants for elementary reactions.Based on theoretical reaction rate ratios,reaction pathways were selected,and a simplified reaction network was derived.It was found that byproducts were formed owing to the decomposition of HFPO and subsequent reactions with excessive oxygen while oxygen tended to participate more in the main reaction under oxygen-deficient conditions.The variations in reaction pathways occurring at different HFP/oxygen molar ratios was well elucidated by comparing with experimental data.This research establishes a robust theoretical foundation for optimizing and regulating the synthesis of HFPO.展开更多
Storing hydrogen in green methanol is a well-known and cost-effective way for long-term energy storage.However,using green methanol in fuel cell technologies requires electrocatalysts with superior resistance to poiso...Storing hydrogen in green methanol is a well-known and cost-effective way for long-term energy storage.However,using green methanol in fuel cell technologies requires electrocatalysts with superior resistance to poisoning induced by intermediate species.This study introduces a new class of palladium-based rare earth(RE)alloys with exceptional resistance to methanol for the oxygen reduction reaction(ORR)and outstanding resistance to carbon monoxide poisoning for the hydrogen oxidation reaction(HOR).The PdEr catalyst achieved unparalleled ORR activity amongst the Pd-based rare earth alloys and demonstrated remarkable resistance to methanol poisoning,which is two orders of magnitude higher than commercial Pt/C catalysts.Furthermore,the PdEr catalyst shows high hydrogen oxidation activity under 100 ppm CO.Comprehensive analysis demonstrates that the RE element-enriched sublayer tuning of the Pd-skin's surface strain is responsible for the enhanced ORR and HOR capabilities.This modification allows for precise control over the adsorption strength of critical intermediates while concurrently diminishing the adsorption energy of methanol and CO on the PdEr surface.展开更多
The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vi...The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vital role of noble metals in electrocatalytic activity,this work focuses on the rational synthesis of Ni-noble metal composite nanocatalysts for overcoming the drawbacks of high cost and susceptible oxidized surfaces of noble metals.The inherent catalytic activity is improved by the altered electronic structure and effective active sites of the catalyst induced by the size effect of noble metal clusters.In particular,a series of Ni-noble metal nanocomposites are successfully synthesized by partially introducing noble metal into Ni with porous interfacial defects derived from Ni-Al layered double hydroxide(LDH).The Ni_(10)Pd_(1)nanocomposite exhibits high OER catalytic activity with an overpotential of 0.279 V at 10 m A/cm^(2),surpassing Ni_(10)Ag_(1)and Ni_(10)Au_(1)counterparts.Furthermore,the average diameter of Pd clusters gradually increases from 5.57 nm to 44.44 nm with the increased proportion of doped Pd,leading to the passivation of catalytic activity due to the exacerbated surface oxidation of Pd in the form of Pd^(2+).After optimization,Ni_(10)Pd_(1)delivers significantly enhanced OER and MOR electroactivities and long-term stability compared to that of Ni_(2)Pd_(1),Ni_(1)Pd_(1)and Ni_(1)Pd_(2),which is conducive to the effective utilization of Pd and alleviation of surface oxidation.展开更多
The structural modulation of metal-based heterostructure plays a vital role in achieving enhanced performances for highly efficient electrocatalysis.Here we design submonolayered Ru-modified Pd mesoporous nanosheets(P...The structural modulation of metal-based heterostructure plays a vital role in achieving enhanced performances for highly efficient electrocatalysis.Here we design submonolayered Ru-modified Pd mesoporous nanosheets(Pd-Ru MNSs)with the exposure of both Pd and Ru active sites as well as the high atomic utilization of two-dimensional structure.The obtained Pd-Ru MNSs can act as a highly efficient multifunctional catalyst for hydrogen evolution reaction(HER)and alcohol oxidation reactions including ethylene glycol oxidation(EGOR)and ethanol oxidation(EOR),offering new opportunities towards the alcohol oxidation assisted hydrogen production.Specifically,Pd-Ru MNSs demonstrate excellent HER performance in alkaline electrolyte,requiring an overpotential of only 16mV to reach 10mAcm^(−2),significantly outperforming Pd mesoporous nanosheets and commercial catalysts.Density functional theory calculations reveal that the Ru sites in Pd-Ru MNSs could facilitate the water adsorption,accelerate the water dissociation,and optimize the hydrogen desorption,leading to the superior HER activity.Pd-Ru MNSs also exhibit high mass activities of 11.19 A mg^(−1)Pd for EGOR and 8.84 A mg^(−1)Pd for EOR,which is 7.8 and 9.6 times than that of commercial Pd/C,respectively.The EGOR reaction pathway over Pd-Ru MNSs was further investigated by using in situ Fourier-transform infrared spectroscopy.展开更多
Formic acid holds great potential as a fuel for low-temperature proton-exchange membrane fuel cells and portable power devices because of its excellent safety profile and high energy density.However,formic acid oxidat...Formic acid holds great potential as a fuel for low-temperature proton-exchange membrane fuel cells and portable power devices because of its excellent safety profile and high energy density.However,formic acid oxidation reactions(FAOR)face challenges such as low catalytic activity,poor stability,and catalyst poisoning.Atomically dispersed catalysts(ADCs)address these issues by providing a direct oxidation pathway,inhibiting catalyst poisoning,and offering well-defined catalytic sites with ultimate atomic efficiency.This review provides a comprehensive summary of recent breakthroughs in ADCs for FAOR.First,we discuss the structural design and mechanism validation methods of ADCs using enhanced sensitivity,in situ/operando,and high-resolution techniques.Next,we summarize bottom-up optimization strategies for ADCs,guided by the structure-activity relationship and reaction mechanisms at the atomic and electronic levels.Finally,we offer insights into device design and scale-up efforts for FAOR applications and provide an overlook from fundamental catalyst design to practical applications.展开更多
Hydrogen peroxide(H_(2)O_(2))electrosynthesis via two-electron oxygen reduction reaction(2e-ORR)is a promising alternative for the energy-intensive anthraquinone process.However,the instability of the catalytic metal ...Hydrogen peroxide(H_(2)O_(2))electrosynthesis via two-electron oxygen reduction reaction(2e-ORR)is a promising alternative for the energy-intensive anthraquinone process.However,the instability of the catalytic metal sites in the state-of-the-art metal single-atom catalysts(M-SACs)hinders their further industrial applications,and the high potential and valueless oxygen product of the conventional anodic oxygen evolution reaction(OER)further limit the economic efficiency of this technology.To address this,a dynamically local structure reconstruction strategy is proposed to in situ transfer the active sites from unstable metal sites to the stable surrounding carbon sites for efficient and durable 2e^(-)ORR electrocatalysis.For the as-designed Mn-N_(3)O-C catalyst,by reconstructing Mn sites into Mn(^(*)OH),the Mn sites were passivated and carbon sites adjacent to the O atom were verified to be the actual active sites by in situ characterization and theoretical calculation.Consequently,Mn-N_(3)O-C exhibited>80%Faradaic efficiency and superior long-term durability over 100 h for H_(2)O_(2)electrosynthesis at~120 mA cm^(-2).In addition,coupling anodic ethylene glycol oxidation reaction(EGOR)further improves the efficiency and economic viability of the H_(2)O_(2)electrosynthesis system.This two-pronged strategy thus opens up a new opportunity for the development of stable H_(2)O_(2)electrosynthesis with low energy consumption and superior economic performance.展开更多
Efficient and innovative nano-catalytic oxidation technologies offer a breakthrough in removing emerging contaminants(ECs)from water,surpassing the limitations of traditional methods.Environmental functional materials...Efficient and innovative nano-catalytic oxidation technologies offer a breakthrough in removing emerging contaminants(ECs)from water,surpassing the limitations of traditional methods.Environmental functional materials(EFMs),particularly high-end oxidation systems using eco-friendly nanomaterials,show promise for absorbing and degrading ECs.This literature review presents a comprehensive analysis of diverse traditional restoration techniques-biological,physical,and chemical-assessing their respective applications and limitations in pesticide-contaminated water purification.Through meticulous comparison,we unequivocally advocate for the imperative integration of environmentally benign nanomaterials,notably titanium-based variants,in forthcoming methodologies.Our in-depth exploration scrutinizes the catalytic efficacy,underlying mechanisms,and adaptability of pioneering titanium-based nanomaterials across a spectrum of environmental contexts.Additionally,strategic recommendations are furnished to surmount challenges and propel the frontiers of implementing eco-friendly nanomaterials in practical water treatment scenarios.展开更多
Herein,three supported catalysts,CuO/Al_(2)O_(3),CeO_(2)/Al_(2)O_(3),and CuO-CeO_(2)/Al_(2)O_(3),were synthesized by the convenient impregnation method to reveal the effect of CeO_(2)addition on catalytic performance ...Herein,three supported catalysts,CuO/Al_(2)O_(3),CeO_(2)/Al_(2)O_(3),and CuO-CeO_(2)/Al_(2)O_(3),were synthesized by the convenient impregnation method to reveal the effect of CeO_(2)addition on catalytic performance and reaction mechanism for toluene oxidation.Compared with CuO/Al_(2)O_(3),the T_(50)and T_(90)(the temperatures at 50%and 90%toluene conversion,respectively)of CuO-CeO_(2)/Al_(2)O_(3)were reduced by 33 and 39°C,respectively.N_(2)adsorptiondesorption experiment,XRD,SEM,EDS mapping,Raman,EPR,H_(2)-TPR,O_(2)-TPD,XPS,NH_(3)-TPD,Toluene-TPD,and in-situ DRIFTS were conducted to characterize these catalysts.The excellent catalytic performance of CuO-CeO_(2)/Al_(2)O_(3)could be attributed to its strong coppercerium interaction and high oxygen vacancies concentration.Moreover,in-situ DRIFTS proved that CuO-CeO_(2)/Al_(2)O_(3)promoted the conversion of toluene to benzoate and accelerated the deep degradation path of toluene.This work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.展开更多
Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uro...Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research.展开更多
The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and u...The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and uncertainties during optimization remains a formidable challenge. In this study, a strategy combining interpretable machine learning with metaheuristic optimization algorithms is employed to optimize the reaction process. First, experimental data from a biodiesel production process are collected to establish a database. These data are then used to construct a predictive model based on artificial neural network (ANN) models. Subsequently, interpretable machine learning techniques are applied for quantitative analysis and verification of the model. Finally, four metaheuristic optimization algorithms are coupled with the ANN model to achieve the desired optimization. The research results show that the methanol: palm fatty acid distillate (PFAD) molar ratio contributes the most to the reaction outcome, accounting for 41%. The ANN-simulated annealing (SA) hybrid method is more suitable for this optimization, and the optimal process parameters are a catalyst concentration of 3.00% (mass), a methanol: PFAD molar ratio of 8.67, and a reaction time of 30 min. This study provides deeper insights into reaction process optimization, which will facilitate future applications in various reaction optimization processes.展开更多
The widespread occurrence of antibiotics in wastewater aroused serious attention.UV-based advanced oxidation processes(UV-AOPs)are powerful technologies in removing antibiotics in wastewater,which include UV/catalyst,...The widespread occurrence of antibiotics in wastewater aroused serious attention.UV-based advanced oxidation processes(UV-AOPs)are powerful technologies in removing antibiotics in wastewater,which include UV/catalyst,UV/H_(2)O_(2),UV/Fenton,UV/persulfate,UV/chlorine,UV/ozone,and UV/peracetic acid.In this review,we collated recent advances in application of UV-AOPs for the abatement of fiuoroquinolones(FQs)as widely used class of antibiotics.Representative FQs of ciprofioxacin,norfioxacin,ofioxacin,and enrofioxacin were most extensively studied in the state-of-art studies.The evolvement of gas-state and solid-state UV light sources was presented and batch and continuous fiow UV reactors were compared towards practical applications in UV-AOPs.Generally,degradation of FQs followed the pseudo-first order kinetics in UV-AOPs and strongly affected by the operating factors and components of water matrix.Participation of reactive species and transformation mechanisms of FQs were compared among different UV-AOPs.Challenges and future prospects were pointed out for providing insights into the practical application of UV-AOPs for antibiotic remediation in wastewater.展开更多
In this study, we proposed a novel method to investigate the advanced oxidation process of neonicotinoids(NNIs) from the perspective of concomitant chemiluminescence(CL) reaction. It was found that in the presence of ...In this study, we proposed a novel method to investigate the advanced oxidation process of neonicotinoids(NNIs) from the perspective of concomitant chemiluminescence(CL) reaction. It was found that in the presence of cobalt ions with cyanoimino NNIs, acetamiprid(ACE) and thiacloprid(THI), could promote peroxymonosulfate and Ru(bpy)_(3)^(2+) to produce strong CL, but no CL occurred with nitro-involved NNIs as alternatives. Experimental dada from UV absorption spectra and chemiluminescence spectra suggested that new cyclic compounds might be formed during the reaction. Based on the results of free radical scavenging experiment and mass spectra, a new degradation and reaction mechanism of cyanoiminocontaining NNIs was proposed. ACE or THI were first attacked by SO_(4)^(·-) to form benzyl radicals, which in turn reacted with the carbon atoms of cyano group through electrophilic addition reaction in the formation of intramolecular ring. Then a redox reaction between Ru(bpy)_(3)^(3+) and imino group immediately took place with CL emission(610 nm). The new mechanistic knowledge would be meaningful for other contaminants for their interactions with PMS.展开更多
The development of efficient and robust non-precious metal electrocatalyst to drive the sluggish hydrogen oxidation reaction(HOR)is the key to the practical application of anion exchange membrane fuel cells(AEMFC),whi...The development of efficient and robust non-precious metal electrocatalyst to drive the sluggish hydrogen oxidation reaction(HOR)is the key to the practical application of anion exchange membrane fuel cells(AEMFC),which relies on the rational regulation of intermediates’binding strength.Herein,we reported a simple strategy to manipulate the adsorption energy of OH^(∗)on electrocatalyst surface via engineering Ni/NbO_(x) heterostructures with manageable oxygen vacancy(Ov).Theoretical calculations confirm that the electronic effect between Ni and NbO_(x) could weaken the hydrogen adsorption on Ni,and the interfacial oxygen vacancy tailor hydroxide binding energy(OHBE).The optimized HBE and OHBE contribute to reduce formation energy of water during the alkaline HOR process.Furthermore,in situ Raman spectroscopy monitor the dynamic process that OH^(∗)adsorbed on oxygen vacancy and react with adjacent H^(∗)adsorbed Ni,confirming the vital role of OH^(∗)for alkaline HOR process.As a result,the optimal Ni/NbO_(x) exhibits a remarkable intrinsic activity with a specific activity of 0.036mA/cm^(2),which is 4-fold than that of pristine Ni counterpart and surpasses most non-precious electrocatalysts ever reported.展开更多
基金Project(52274348)supported by the National Natural Science Foundation of ChinaProject(2022JH1/10400024)supported by the Major Projects for the“Revealed Top”Science and Technology of Liaoning Province,China。
文摘Applying bio-oxidation waste solution(BOS)to chemical-biological two-stage oxidation process can significantly improve the bio-oxidation efficiency of arsenopyrite.This study aims to clarify the enhanced oxidation mechanism of arsenopyrite by evaluating the effects of physical and chemical changes of arsenopyrite in BOS chemical oxidation stage on mineral dissolution kinetics,as well as microbial growth activity and community structure composition in bio-oxidation stage.The results showed that the chemical oxidation contributed to destroying the physical and chemical structure of arsenopyrite surface and reducing the particle size,and led to the formation of nitrogenous substances on mineral surface.These chemical oxidation behaviors effectively promoted Fe^(3+)cycling in the bio-oxidation system and weakened the inhibitory effect of the sulfur film on ionic diffusion,thereby enhancing the dissolution kinetics of the arsenopyrite.Therefore,the bio-oxidation efficiency of arsenopyrite was significantly increased in the two-stage oxidation process.After 18 d,the two-stage oxidation process achieved total extraction rates of(88.8±2.0)%,(86.7±1.3)%,and(74.7±3.0)%for As,Fe,and S elements,respectively.These values represented a significant increase of(50.8±3.4)%,(47.1±2.7)%,and(46.0±0.7)%,respectively,compared to the one-stage bio-oxidation process.
基金National Natural Science Foundation of China(52071274)Key Research and Development Projects of Shaanxi Province(2023-YBGY-442)Science and Technology Nova Project-Innovative Talent Promotion Program of Shaanxi Province(2020KJXX-062)。
文摘To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.
基金financial support from National Key R&D Program of China (No.2019YFD1100200)National Natural Science Foundation of China (Nos.51878431,51961145106)+2 种基金Shanghai Rising-Star Program (No.20QC1401200)Shanghai Science and Technology Committee (No.19DZ1208400)State Key Laboratory of Pollution Control and Resource Reuse Foundation,(No.PCRRE20002)。
文摘In the field of advanced oxidation processes(AOPs) of wastewater, many materials can be used as heterogeneous catalysts. The role of these catalysts is to activate oxidants and generate reactive oxygen species(ROS) to decompose refractory pollutants. Perovskite oxide, an emerging catalyst in the field of AOPs, has been extensively studied in wastewater treatment. Nevertheless, the application of perovskite in AOP systems still faces some problems, such as leaching of metal ions, a small surface area, a low number of active sites, etc. Herein, this critical review comparatively examines the activation mechanisms of peroxymonosulfate, hydrogen peroxide, and peroxydisulfate. Furthermore, the formation pathways of oxidizing species based on recent advances in experimental and theoretical studies were evaluated. In addition, the impacts of water parameters and constituents such as initial p H, oxidant concentration, catalyst dosage,natural organic matter, halide, phosphate, and carbonate were discussed. Finally, a critical discussion and prospects of mechanism exploration and possible materials development are proposed to confront the existing challenges in the application of perovskite oxides in AOPs.
基金supported by the National Key Research and Development Program of China(2022YFC3205300)the National Natural Science Foundation of China(22176124).
文摘Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.
文摘The electrocatalytic urea oxidation reaction(UOR)has emerged as an energy-efficient alternative to the traditional oxygen evolution reaction for hydrogen production,with mechanistic understanding being critical for the rational design of catalysts.This review systematically summarizes recent advances in in situ characterization techniques for elucidating the dynamic reaction mechanisms of UOR.Studies reveal that phase transitions,valence state migration,and electronic structure evolution of catalysts under operational conditions are key factors governing activity and stability.Techniques such as in situ X-ray diffraction,X-ray absorption spectroscopy,Raman spectroscopy,and Fourier-transform infrared spectroscopy enable real-time monitoring of catalyst reconstruction,intermediate evolution,and interfacial adsorption behavior,overcoming the environmental deviations inherent in conventional ex situ characterization.When combined with theoretical calculations,these methods provide direct evidence for identifying active-site configurations,reaction pathways,and rate-determining steps.In addition,special emphasis is placed on multimodal in situ strategies for deciphering synergistic effects in nickel-based catalysts,while current challenges,including non-alkaline systems,real wastewater environments,and multi-metal cooperation mechanisms,are critically discussed.Future research should focus on developing novel in situ approaches for complex systems and establishing a mutually reinforcing framework integrating theoretical prediction and experimental validation,thereby advancing UOR catalyst design from empirical exploration to mechanism-guided optimization.
基金supported by Natural Science Foundation of China(Nos.52070133,42107073,42477075)Natural Science Foundation of Sichuan Province(No.2024NSFSC0130)+2 种基金the Sichuan Science and Technology Program(No.2024NSFTD0014)Key Laboratory of Jiangxi Province for Persistent Pollutants Prevention Control and Resource Reuse(No.2023SSY02061)Key R&D Program of Heilongjiang Province(No.2023ZX02C01)。
文摘Low-valent sulfur oxy-acid salts(LVSOs)represent a category of oxygen-containing salts characterized by their potent reducing capabilities.Notably,sulfite,dithionite,and thiosulfate are prevalent reducing agents that are readily available,cost-effective,and exhibit minimal ecological toxicity.These LVSOs have the ability to generate or promote the generation of strong oxidants or reductants,which makes them widely used in advanced oxidation processes(AOPs)and advanced reduction processes(ARPs).This article provides a comprehensive review of the recent advancements in AOPs and ARPs involving LVSOs,alongside an examination of the fundamental principles governing the generation of active species within these processes.LVSOs fulfill three primary functions in AOPs:Serving as sources of reactive oxygen species(ROS),auxiliary agents,and activators.Particular attention is devoted to elucidating the reaction mechanisms through which LVSOs,in conjunction with metal ions,metal oxides,ultraviolet light(UV),and ozone,produce potent oxidizing agents in both homogeneous and heterogeneous systems.Regarding ARPs,this review delineates the mechanisms by which LVSOs generate strong reducing agents,including hydrated electrons,hydrogen radicals,and sulfite radicals,under UV irradiation,while also exploring the interactions between these reductants and pollutants.The review identifies existing gaps within the current framework and proposes future research avenues to address these challenges.
文摘The employment of single atom catalysts(SACs)remarkably increases atomic utilization and catalytic efficiency in various electrochemical processes,especially when coupled with metal clusters/nanoparticles.However,the synergistic effects mainly focus on the energetics of key intermediates during the electrocatalysis,while the properties of electrode surface and electric-double-layer(EDL)structure are largely overlooked.Herein,we report the synthesis of Ru nanoparticles integrated with neighboring Ru single atoms on nitrogen doped carbon(Ru1,n/NC)as efficient catalysts toward hydrogen oxidation reaction(HOR)under alkaline electrolytes.Electrochemical data,in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy,and density functional theory calculations reveal that the positively charged Ru single atoms could lead to the dynamically regulated proportion of strongly hydrogen-bonded interfacial water structure with O-down conformation and optimized connectivity of the hydrogen-bond network in the EDL region,which contribute to the accelerated diffusion of hydroxide ions to the electrified interfaces.Consequently,the obtained Ru1,n/NC catalyst displays remarkable HOR performance with the mass activity of 1.15 mAμgPGM^(-1) under alkaline electrolyte.This work demonstrates the promise of single atoms for interfacial water environment adjustment and mass transfer process modulation,providing new insights into rational design of highly-effective SAC-based electrocatalysts.
基金supported by the National Key Research&Development Program of China(2021YFB3803200)the National Natural Science Foundation of China(22288102).
文摘Hexafluoropropylene oxide(HFPO)is a crucial fluorinated chemical mainly synthesized from hexafluoropropylene(HFP)through the oxidation of oxygen.However,the reaction network and kinetic characteristics are not fully understood yet,resulting in a lack of theoretical basis for synthesis process improvement.Here,the free radical reaction mechanism and complete reaction network involved in the noncatalytic oxidation of HFP to synthesize HFPO was explored by density functional theory.Transition state theory was employed to calculate the intrinsic reaction rate constants for elementary reactions.Based on theoretical reaction rate ratios,reaction pathways were selected,and a simplified reaction network was derived.It was found that byproducts were formed owing to the decomposition of HFPO and subsequent reactions with excessive oxygen while oxygen tended to participate more in the main reaction under oxygen-deficient conditions.The variations in reaction pathways occurring at different HFP/oxygen molar ratios was well elucidated by comparing with experimental data.This research establishes a robust theoretical foundation for optimizing and regulating the synthesis of HFPO.
基金supported by the National Key Research and Development Program of China,China(2023YFB4006202)the National Natural Science Foundation of China,China(22272206)the Natural Science Foundation of Hunan Province,China(2023JJ10061).
文摘Storing hydrogen in green methanol is a well-known and cost-effective way for long-term energy storage.However,using green methanol in fuel cell technologies requires electrocatalysts with superior resistance to poisoning induced by intermediate species.This study introduces a new class of palladium-based rare earth(RE)alloys with exceptional resistance to methanol for the oxygen reduction reaction(ORR)and outstanding resistance to carbon monoxide poisoning for the hydrogen oxidation reaction(HOR).The PdEr catalyst achieved unparalleled ORR activity amongst the Pd-based rare earth alloys and demonstrated remarkable resistance to methanol poisoning,which is two orders of magnitude higher than commercial Pt/C catalysts.Furthermore,the PdEr catalyst shows high hydrogen oxidation activity under 100 ppm CO.Comprehensive analysis demonstrates that the RE element-enriched sublayer tuning of the Pd-skin's surface strain is responsible for the enhanced ORR and HOR capabilities.This modification allows for precise control over the adsorption strength of critical intermediates while concurrently diminishing the adsorption energy of methanol and CO on the PdEr surface.
基金support by the National Natural Science Foundation of China(Nos.U20A20123,51874357,22379166)Natural Science Foundation for Distinguished Young Scholars of Hunan Province(No.2022JJ10089)。
文摘The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vital role of noble metals in electrocatalytic activity,this work focuses on the rational synthesis of Ni-noble metal composite nanocatalysts for overcoming the drawbacks of high cost and susceptible oxidized surfaces of noble metals.The inherent catalytic activity is improved by the altered electronic structure and effective active sites of the catalyst induced by the size effect of noble metal clusters.In particular,a series of Ni-noble metal nanocomposites are successfully synthesized by partially introducing noble metal into Ni with porous interfacial defects derived from Ni-Al layered double hydroxide(LDH).The Ni_(10)Pd_(1)nanocomposite exhibits high OER catalytic activity with an overpotential of 0.279 V at 10 m A/cm^(2),surpassing Ni_(10)Ag_(1)and Ni_(10)Au_(1)counterparts.Furthermore,the average diameter of Pd clusters gradually increases from 5.57 nm to 44.44 nm with the increased proportion of doped Pd,leading to the passivation of catalytic activity due to the exacerbated surface oxidation of Pd in the form of Pd^(2+).After optimization,Ni_(10)Pd_(1)delivers significantly enhanced OER and MOR electroactivities and long-term stability compared to that of Ni_(2)Pd_(1),Ni_(1)Pd_(1)and Ni_(1)Pd_(2),which is conducive to the effective utilization of Pd and alleviation of surface oxidation.
基金financial support from the National Natural Science Foundation of China(No.52471219)the Fundamental Research Funds for the Central Universities(No.00007838)+5 种基金financial support from the National Natural Science Foundation of China(No.52471220 and U2441264)the Guangdong Basic and Applied Basic Research Foundation(No.2022A1515140051)financial support from the National Natural Science Foundation of China(No.92163209)Beijing Natural Science Foundation(No.JQ22004)financial support from the National Natural Science Foundation of China(No.52476146)Guangdong Basic and Applied Basic Research Foundation(2023A1515140059,2025A1515011255).
文摘The structural modulation of metal-based heterostructure plays a vital role in achieving enhanced performances for highly efficient electrocatalysis.Here we design submonolayered Ru-modified Pd mesoporous nanosheets(Pd-Ru MNSs)with the exposure of both Pd and Ru active sites as well as the high atomic utilization of two-dimensional structure.The obtained Pd-Ru MNSs can act as a highly efficient multifunctional catalyst for hydrogen evolution reaction(HER)and alcohol oxidation reactions including ethylene glycol oxidation(EGOR)and ethanol oxidation(EOR),offering new opportunities towards the alcohol oxidation assisted hydrogen production.Specifically,Pd-Ru MNSs demonstrate excellent HER performance in alkaline electrolyte,requiring an overpotential of only 16mV to reach 10mAcm^(−2),significantly outperforming Pd mesoporous nanosheets and commercial catalysts.Density functional theory calculations reveal that the Ru sites in Pd-Ru MNSs could facilitate the water adsorption,accelerate the water dissociation,and optimize the hydrogen desorption,leading to the superior HER activity.Pd-Ru MNSs also exhibit high mass activities of 11.19 A mg^(−1)Pd for EGOR and 8.84 A mg^(−1)Pd for EOR,which is 7.8 and 9.6 times than that of commercial Pd/C,respectively.The EGOR reaction pathway over Pd-Ru MNSs was further investigated by using in situ Fourier-transform infrared spectroscopy.
基金supported by The National Key R&D Program of China(2022YFA1505700)National Natural Science Foundation of China(22475214 and 22205232)+3 种基金Talent Plan of Shanghai Branch,Chinese Academy of Sciences(CASSHB-QNPD-2023-020)Natural Science Foundation of Fujian Province(2023J06044)the SelfDeployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences(CXZX-2022-JQ06 and CXZX-2022-GH03)the Postdoctoral Fellowship Program of the China Postdoctoral Science Foundation(CPSF,GZC20241727)。
文摘Formic acid holds great potential as a fuel for low-temperature proton-exchange membrane fuel cells and portable power devices because of its excellent safety profile and high energy density.However,formic acid oxidation reactions(FAOR)face challenges such as low catalytic activity,poor stability,and catalyst poisoning.Atomically dispersed catalysts(ADCs)address these issues by providing a direct oxidation pathway,inhibiting catalyst poisoning,and offering well-defined catalytic sites with ultimate atomic efficiency.This review provides a comprehensive summary of recent breakthroughs in ADCs for FAOR.First,we discuss the structural design and mechanism validation methods of ADCs using enhanced sensitivity,in situ/operando,and high-resolution techniques.Next,we summarize bottom-up optimization strategies for ADCs,guided by the structure-activity relationship and reaction mechanisms at the atomic and electronic levels.Finally,we offer insights into device design and scale-up efforts for FAOR applications and provide an overlook from fundamental catalyst design to practical applications.
基金supported by the National Natural Science Foundation of China(22379111 and 22179093)。
文摘Hydrogen peroxide(H_(2)O_(2))electrosynthesis via two-electron oxygen reduction reaction(2e-ORR)is a promising alternative for the energy-intensive anthraquinone process.However,the instability of the catalytic metal sites in the state-of-the-art metal single-atom catalysts(M-SACs)hinders their further industrial applications,and the high potential and valueless oxygen product of the conventional anodic oxygen evolution reaction(OER)further limit the economic efficiency of this technology.To address this,a dynamically local structure reconstruction strategy is proposed to in situ transfer the active sites from unstable metal sites to the stable surrounding carbon sites for efficient and durable 2e^(-)ORR electrocatalysis.For the as-designed Mn-N_(3)O-C catalyst,by reconstructing Mn sites into Mn(^(*)OH),the Mn sites were passivated and carbon sites adjacent to the O atom were verified to be the actual active sites by in situ characterization and theoretical calculation.Consequently,Mn-N_(3)O-C exhibited>80%Faradaic efficiency and superior long-term durability over 100 h for H_(2)O_(2)electrosynthesis at~120 mA cm^(-2).In addition,coupling anodic ethylene glycol oxidation reaction(EGOR)further improves the efficiency and economic viability of the H_(2)O_(2)electrosynthesis system.This two-pronged strategy thus opens up a new opportunity for the development of stable H_(2)O_(2)electrosynthesis with low energy consumption and superior economic performance.
基金supported by the Research Platform Open Fund Project of Zhejiang Industry and Trade Vocation College(No.Kf202203)the Scientific Research Project of CCCC First Harbor Engineering Company Ltd.(No.2022-7-2)+3 种基金the National Natural Science Foundation of China(No.22406142)the Fellowship of China National Postdoctoral Program for Innovative Talents(No.BX20230262)the Fellowship of China Postdoctoral Science Foundation(No.2023M732636)the Shanghai Post-doctoral Excellence Program(No.2023755).
文摘Efficient and innovative nano-catalytic oxidation technologies offer a breakthrough in removing emerging contaminants(ECs)from water,surpassing the limitations of traditional methods.Environmental functional materials(EFMs),particularly high-end oxidation systems using eco-friendly nanomaterials,show promise for absorbing and degrading ECs.This literature review presents a comprehensive analysis of diverse traditional restoration techniques-biological,physical,and chemical-assessing their respective applications and limitations in pesticide-contaminated water purification.Through meticulous comparison,we unequivocally advocate for the imperative integration of environmentally benign nanomaterials,notably titanium-based variants,in forthcoming methodologies.Our in-depth exploration scrutinizes the catalytic efficacy,underlying mechanisms,and adaptability of pioneering titanium-based nanomaterials across a spectrum of environmental contexts.Additionally,strategic recommendations are furnished to surmount challenges and propel the frontiers of implementing eco-friendly nanomaterials in practical water treatment scenarios.
基金supported by the Science and Technology Program of Guangzhou,China(No.202002020020)the National Natural Science Foundation of China(Nos.51878292 and 42002035).
文摘Herein,three supported catalysts,CuO/Al_(2)O_(3),CeO_(2)/Al_(2)O_(3),and CuO-CeO_(2)/Al_(2)O_(3),were synthesized by the convenient impregnation method to reveal the effect of CeO_(2)addition on catalytic performance and reaction mechanism for toluene oxidation.Compared with CuO/Al_(2)O_(3),the T_(50)and T_(90)(the temperatures at 50%and 90%toluene conversion,respectively)of CuO-CeO_(2)/Al_(2)O_(3)were reduced by 33 and 39°C,respectively.N_(2)adsorptiondesorption experiment,XRD,SEM,EDS mapping,Raman,EPR,H_(2)-TPR,O_(2)-TPD,XPS,NH_(3)-TPD,Toluene-TPD,and in-situ DRIFTS were conducted to characterize these catalysts.The excellent catalytic performance of CuO-CeO_(2)/Al_(2)O_(3)could be attributed to its strong coppercerium interaction and high oxygen vacancies concentration.Moreover,in-situ DRIFTS proved that CuO-CeO_(2)/Al_(2)O_(3)promoted the conversion of toluene to benzoate and accelerated the deep degradation path of toluene.This work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.
基金financially supported by National Natural Science Foundation of China(No.22207113 to J.Zhang)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110588to J.Zhang)Natural Science Foundation of Shanghai Municipality(No.22ZR1474000 to L.Wen)。
文摘Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research.
基金supported by the National Natural Science Foundation of China(22408227,22238005)the Postdoctoral Research Foundation of China(GZC20231576).
文摘The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and uncertainties during optimization remains a formidable challenge. In this study, a strategy combining interpretable machine learning with metaheuristic optimization algorithms is employed to optimize the reaction process. First, experimental data from a biodiesel production process are collected to establish a database. These data are then used to construct a predictive model based on artificial neural network (ANN) models. Subsequently, interpretable machine learning techniques are applied for quantitative analysis and verification of the model. Finally, four metaheuristic optimization algorithms are coupled with the ANN model to achieve the desired optimization. The research results show that the methanol: palm fatty acid distillate (PFAD) molar ratio contributes the most to the reaction outcome, accounting for 41%. The ANN-simulated annealing (SA) hybrid method is more suitable for this optimization, and the optimal process parameters are a catalyst concentration of 3.00% (mass), a methanol: PFAD molar ratio of 8.67, and a reaction time of 30 min. This study provides deeper insights into reaction process optimization, which will facilitate future applications in various reaction optimization processes.
基金the financial support from National Natural Science Foundation of China(Nos.52100204 and 52330005)Beijing Outstanding Young Scientist Program(No.BJJWZYJH01201910004016)。
文摘The widespread occurrence of antibiotics in wastewater aroused serious attention.UV-based advanced oxidation processes(UV-AOPs)are powerful technologies in removing antibiotics in wastewater,which include UV/catalyst,UV/H_(2)O_(2),UV/Fenton,UV/persulfate,UV/chlorine,UV/ozone,and UV/peracetic acid.In this review,we collated recent advances in application of UV-AOPs for the abatement of fiuoroquinolones(FQs)as widely used class of antibiotics.Representative FQs of ciprofioxacin,norfioxacin,ofioxacin,and enrofioxacin were most extensively studied in the state-of-art studies.The evolvement of gas-state and solid-state UV light sources was presented and batch and continuous fiow UV reactors were compared towards practical applications in UV-AOPs.Generally,degradation of FQs followed the pseudo-first order kinetics in UV-AOPs and strongly affected by the operating factors and components of water matrix.Participation of reactive species and transformation mechanisms of FQs were compared among different UV-AOPs.Challenges and future prospects were pointed out for providing insights into the practical application of UV-AOPs for antibiotic remediation in wastewater.
基金financial supports from the National Natural Science Foundation of China(Nos.81960600and 81760601)the Natural Science Foundation of Jiangxi Province(Nos.20192BAB205089 and 20192BAB205091)。
文摘In this study, we proposed a novel method to investigate the advanced oxidation process of neonicotinoids(NNIs) from the perspective of concomitant chemiluminescence(CL) reaction. It was found that in the presence of cobalt ions with cyanoimino NNIs, acetamiprid(ACE) and thiacloprid(THI), could promote peroxymonosulfate and Ru(bpy)_(3)^(2+) to produce strong CL, but no CL occurred with nitro-involved NNIs as alternatives. Experimental dada from UV absorption spectra and chemiluminescence spectra suggested that new cyclic compounds might be formed during the reaction. Based on the results of free radical scavenging experiment and mass spectra, a new degradation and reaction mechanism of cyanoiminocontaining NNIs was proposed. ACE or THI were first attacked by SO_(4)^(·-) to form benzyl radicals, which in turn reacted with the carbon atoms of cyano group through electrophilic addition reaction in the formation of intramolecular ring. Then a redox reaction between Ru(bpy)_(3)^(3+) and imino group immediately took place with CL emission(610 nm). The new mechanistic knowledge would be meaningful for other contaminants for their interactions with PMS.
基金supported by Jilin Province Science and Technology Development Program(Nos.20200201001JC,20210502002ZP,20230101367JC,20220301011GX)Jilin Province Science and Technology Major Project(No.222648GX0105103875).
文摘The development of efficient and robust non-precious metal electrocatalyst to drive the sluggish hydrogen oxidation reaction(HOR)is the key to the practical application of anion exchange membrane fuel cells(AEMFC),which relies on the rational regulation of intermediates’binding strength.Herein,we reported a simple strategy to manipulate the adsorption energy of OH^(∗)on electrocatalyst surface via engineering Ni/NbO_(x) heterostructures with manageable oxygen vacancy(Ov).Theoretical calculations confirm that the electronic effect between Ni and NbO_(x) could weaken the hydrogen adsorption on Ni,and the interfacial oxygen vacancy tailor hydroxide binding energy(OHBE).The optimized HBE and OHBE contribute to reduce formation energy of water during the alkaline HOR process.Furthermore,in situ Raman spectroscopy monitor the dynamic process that OH^(∗)adsorbed on oxygen vacancy and react with adjacent H^(∗)adsorbed Ni,confirming the vital role of OH^(∗)for alkaline HOR process.As a result,the optimal Ni/NbO_(x) exhibits a remarkable intrinsic activity with a specific activity of 0.036mA/cm^(2),which is 4-fold than that of pristine Ni counterpart and surpasses most non-precious electrocatalysts ever reported.
