In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to sign...In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to significant environmental issues[1].Currently,sustainable biomass resources have attracted much attention as potential substitutes to fossil fuels for producing biofuels and commodity chemicals[2].展开更多
The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human health.Therefore,it is very important to develop a con-venient and effective method ...The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human health.Therefore,it is very important to develop a con-venient and effective method to detect and degrade phenolic compounds.Herein,we report a new keggin-type polyoxometallate-based metal-organic complex self-assembled under solvothermal condition,{[Cu(dap)(3-PA)]4(SiW_(12)O_(40))(H_(2)O)_(2)}·2H_(2)O(1,dap=1,2-diaminopropane,3-HPA=3-pyridineacrylic acid).1 shows an interesting 1D ladder-like structure.As a bifunctional catalyst,1 can be employed as a colori-metric sensor toward phenol with the relatively low detection limit(LOD)of 0.36μmol/L(S/N=3)in the wide range(0.001-0.1 mmol/L).The title colorimetric sensor is applied to determine phenol in various water environment with good recoveries ranging from 95%-105%.In addition,1 also exhibits excellent photocatalytic degradation toward phenol under visible light with the highest removal efficiency at 96%for 100 min and wide pH universality.The selectivity,stability and reliability of the detection of 1 towards phenol,as well as the detection for 4-chlorophenol,o-cresol,4-nitrophenol and phloroglucinol were stud-ied.Furthermore,the photocatalytic reaction kinetics and the mechanisms of photodegradation of phenol were also investigated in detail.展开更多
The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling.Herein,in this work,CuO/Co_(3)O_(4)with heterogeneous interfa...The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling.Herein,in this work,CuO/Co_(3)O_(4)with heterogeneous interface is successfully constructed as a bifunctional catalyst for the electrooxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid and the electroreduction of nitrate to ammonia(NH_(3)).The open-circuit potential spontaneous experiment shows that more 5-hydroxymethylfurfural molecules are adsorbed in the Helmholtz layer of the CuO/Co_(3)O_(4)composite,which certifies that the CuO/Co_(3)O_(4)heterostructure is conducive to the kinetic adsorption of 5-hydroxymethylfurfural.In situ electrochemical impedance spectroscopy further shows that CuO/Co_(3)O_(4)has faster reaction kinetics and lower reaction potential in oxygen evolution reaction and 5-hydroxymethylfurfural electrocatalytic oxidation.Moreover,CuO/Co_(3)O_(4)also has a good reduction effect on NO_(3)^(-).The ex-situ Raman spectroscopy shows that under the reduction potential,the metal oxide is reduced,and the generated Cu_(2)O can be used as a new active site for the reaction to promote the electrocatalytic conversion of NO_(3)^(-)to NH_(3) synthesis.This work provides valuable guidance for the synthesis of value-added chemicals by 5-hydroxymethylfurfural electrocatalytic oxidation coupled with NO_(3)^(-)while efficiently producing NH_(3).展开更多
Deep degradation of organic pollutants by sunlight-induced coupled photocatalytic and Fenton (photo-Fenton) reactions is of immense importance for water purification. In this work, we report a novel bifunctional catal...Deep degradation of organic pollutants by sunlight-induced coupled photocatalytic and Fenton (photo-Fenton) reactions is of immense importance for water purification. In this work, we report a novel bifunctional catalyst (Fe-PEI-CN) by codoping graphitic carbon nitride (CN) with polyethyleneimine ethoxylated (PEI) and Fe species, which demonstrated high activity during p-chlorophenol (p-ClPhOH) degradation via H_(2)O_(2) from the photocatalytic process. The relationship between the catalytic efficiency and the structure was explored using diff erent characterization methods. The Fe modification of CN was achieved through Fe-N coordination, which ensured high dispersion of Fe species and strong stability against leaching during liquid- phase reactions. The Fe modification initiated the Fenton reaction by activating H_(2)O_(2) into ·OH radicals for deep degradation of p-ClPhOH. In addition, it eff ectively promoted light absorption and photoelectron-hole (e-h ^(+) ) separation, corresponding to improved photocatalytic activity. On the other hand, PEI could significantly improve the ability of CN to generate H_(2)O_(2) through visible light photocatalysis. The maximum H_(2)O_(2) yield reached up to 102.6 μmol/L, which was 22 times higher than that of primitive CN. The cooperation of photocatalysis and the self-Fenton reaction has led to high-activity mineralizing organic pollutants with strong durability, indicating good potential for practical application in wastewater treatment.展开更多
The selective production of gasoline from syngas is an important technology in the current stage of energy transformation and upgrading.The product distribution of traditional Fischer-Tropsch synthesis follows the And...The selective production of gasoline from syngas is an important technology in the current stage of energy transformation and upgrading.The product distribution of traditional Fischer-Tropsch synthesis follows the Anderson-Schulz-Flory(ASF)distribution law,and breaking through the distribution limitations to produce more gasoline components depends largely on the design and development of high-performance catalysts.In this paper,the recent research progress of bifunctional catalysts for gasoline production from syngas with high selectivity is summarized.This includes core-shell structure catalyst,microporous zeolite supported catalyst,mesoporous zeolite supported catalyst,metal oxide-zeolite relay catalyst.Moreover,the reaction mechanisms are summarized.The future prospects of catalysts for the high-selectivity synthesis of gasoline from syngas is also discussed.The current review will provide insights into the bifunctional catalysts for one-step syngas conversion to gasoline.展开更多
A series of CuO-ZnO-Al2O3-La2O3/HZSM-5 biftmctional catalysts with various La loadings for dimethyl ether (DME) directly synthesized from CO2 hydrogenation were prepared. The catalysts were characterized with N2 ads...A series of CuO-ZnO-Al2O3-La2O3/HZSM-5 biftmctional catalysts with various La loadings for dimethyl ether (DME) directly synthesized from CO2 hydrogenation were prepared. The catalysts were characterized with N2 adsorption-desorption, X-ray diffraction (XRD), H2 temperature-programmed reduction (H2-TPR), NH3 temperature-programmed desorption (NH3-TPD) and N2O titration techniques, and tested for the synthesis of DME directly from CO2 hydrogenation in a fixed-bed reactor. The results showed that the reducibility, dispersion ofbifunctional catalysts were strongly dependent on the addition of La. With the addition of appropri- ate amount of La, the crystaUite size of CuO was decreased and the dispersion of Cu on the surface was enhanced, which resulted in the increased conversion of CO2. It was also found that the selectivity to DME was related to the intensity and amount of strong acid site on the catalyst surface. The presence of La favored the production of DME, and the optimum catalytic activity was obtained when the amount of La was 2.0 wt.%.展开更多
A series of ZnO-ZrO_(2) solid solutions with different Zn contents were synthesized by the urea coprecipitation method,which were coupled with H-ZSM-5 zeolite to form bifunctional catalysts.As a new benzene alkylation...A series of ZnO-ZrO_(2) solid solutions with different Zn contents were synthesized by the urea coprecipitation method,which were coupled with H-ZSM-5 zeolite to form bifunctional catalysts.As a new benzene alkylation reagent,syngas was used instead of methanol to realize the efficient conversion of syngas and benzene into toluene and xylene.A suitable ratio of ZnO-ZrO_(2) led to the significant improvement in the catalytic performance,and a suitable amount of acid helped to increase the selectivity of toluene/xylene and reduce the selectivity of the by-products ethylbenzene and C^(9+) aromatics.The highest benzene conversion of 89.2%and toluene/xylene selectivity of 88.7%were achieved over 10%ZnO-ZrO_(2)&H-ZSM-5(Si/Al=23)at a pressure of 3 MPa and a temperature of 450℃.In addition,the effect of the zeolite framework structure on product distribution was examined.Similar to the molecular dynamics of aromatic hydrocarbons,H-ZSM-5 zeolites comprise 10-membered-ring pores,which are beneficial to the activation of benzene;hence,the conversion of benzene is higher.H-ZSM-35 and HMOR zeolites exhibited small eight-membered-ring channels,which were not conducive to the passage of benzene;hence,the by-product ethylbenzene exhibits a higher selectivity.The distance between the active centers of the bifunctional catalysts was the main factor affecting the catalytic performance,and the powder mixing method was more conducive to the conversion of syngas and benzene.展开更多
The rational design and development of cost-effective,high-performance,and stable bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts are essential for rechargeable zinc-air b...The rational design and development of cost-effective,high-performance,and stable bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts are essential for rechargeable zinc-air batteries.Herein,a novel FeCo composite composed of alloy nanoparticles embedded in an N,S dual-doped carbon matrix(FeCo/NSC)was prepared via one-step carbonization of amphiphilic dodecanethiol-metal salts wrapped in carbon nitride(C_(3)N_(4)).The compact combination of dual metalalloys and dual-doped carbon endowed the composite with the active sites for the ORR and OER,achieving efficient electrical transmission and highly efficient bifunctional catalytic performance.The obtained FeCo-1/NSC catalyst exhibited excellent electrocatalytic activity with a half-wave potential of 0.82 V(vs.RHE)for the ORR and a low overpotential of 0.325 V at 10 mA cm^(-2) for the OER.The liquid Zn-air battery with FeCo-1/NSC as an air electrode displayed excellent charge-discharge performance,high power density,and robust charge-discharge stability for 150 h compared to the 20%Pt/C+RuO_(2) counterpart.Furthermore,the FeCo-1/NSC-based flexible solid-state Zn-air battery exhibited a higher power density and good charge-discharge stability over 10 h of operation.Thus,a promising strategy for bifunctional electrocatalyst development as part of rechargeable and wearable Zn-air batteries was provided.展开更多
The utilization of non-noble metal catalysts with robust and highly efficient electrocatalytic activity for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)are extremely important for the large-scale...The utilization of non-noble metal catalysts with robust and highly efficient electrocatalytic activity for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)are extremely important for the large-scale implementation of renewable energy devices.Integration of bifunctional electrocatalysts on both anode and cathode electrodes remains a significant challenge.Herein,we report on a novel and facile strategy to construct the ordered and aligned MoS_(2)nanosheet-encapsulated metal–organic frameworks(MOFs)derived hollow CoS polyhedron,in-situ grown on a nickel foam(NF).The starfish-like MoS_(2)/CoS/NF heterojunctions were formed due to the ordered growth of the material caused by NF substrate.The optimized 2-MoS_(2)/CoS/NF heterojunction exhibits robust bifunctional electrocatalytic activity with a low overpotential of 67 and 207 m V toward the HER and OER at 10 mA cm^(-2),and the long-term stability,which exceeds most of the reported bifunctional electrocatalysts.Such high electrocatalytic performance arises due to the synergistic effect between the MoS_(2)and CoS phases across the interface,the abundant active sites,as well as the hierarchical pore framework,which collectively enhance the mass and electron transfer during the reactions.The work provides a promising approach to fabricating bifunctional catalysts with custom-designed heterojunctions and remarkable performance for applications in electrochemical energy devices and related areas.展开更多
Zinc-air batteries(ZABs) with high energy density and safety are promising as next-generation energy storage systems, while their applications are severely hindered by the sluggish reaction kinetic of air cathodes. De...Zinc-air batteries(ZABs) with high energy density and safety are promising as next-generation energy storage systems, while their applications are severely hindered by the sluggish reaction kinetic of air cathodes. Developing a bifunctional catalyst with high activity and durability is an effective strategy to address the above challenges. Herein, a Co_(3)O_(4)/Mn_(3)O_(4) nanohybrid with heterointerfaces is designed as advanced cathode catalyst for ZABs. Density functional theory calculations show the heterogeneous interface between Co_(3)O_(4)/Mn_(3)O_(4) can improve the dynamics of carrier transport and thus enhancing the catalytic activity and durability. The Co_(3)O_(4)/Mn_(3)O_(4) catalyst anchored on reduced graphene oxide(rGO)exhibits high oxygen reduction reaction(ORR) activity with a half-wave potential of 0.86 V, and excellent oxygen evolution reaction(OER) activity with the potential of 1.59 V at 10 mA cm^(-2) , which are comparable to the commercial noble metal catalysts. The improved ORR/OER catalytic activity is ascribed to the synergistic effect of heterointerfaces between Co_(3)O_(4) and Mn_(3)O_(4)as well as the improved conductivity and contact area of oxygen/catalysts/electrolytes three-phase interface by r GO. Furthermore, a home-made ZAB based on Co_(3)O_(4)/Mn_(3)O_(4)/r GO shows a high open circuit voltage of 1.54 V, a large power density of 194.6 mW cm^(-2) and good long-term cycling stability of nearly 400 h at 5 mA cm^(-2) , which affords a promising bifunctional oxygen catalyst for rechargeable ZABs.展开更多
A series of Pd/MIL-53(Al) heterogeneous bifunctional catalysts with di erent Pd contents were prepared by an impregnation method. The prepared metal–organic frameworks MIL-53(Al) and catalysts were characterized by X...A series of Pd/MIL-53(Al) heterogeneous bifunctional catalysts with di erent Pd contents were prepared by an impregnation method. The prepared metal–organic frameworks MIL-53(Al) and catalysts were characterized by XRD, SEM, HRTEM,FT-IR and N2 adsorption/desorption techniques. The results showed that MIL-53(Al) was synthesized successfully, and the structure was unchanged during and after the preparation of the catalysts. The Pd nanoparticles(NPs) with an average particle size of 4.6 nm were uniformly dispersed on the MIL-53(Al). The catalyst exhibited good catalytic activity in the selective oxidation of liquid methanol to methyl formate. Under the conditions of 150 °C, 2 MPa O2 and solvent-free for5 h, the conversion of methanol could reach 60.3%, and the selectivity of methyl formate was up to 62.2%. In addition, the Pd/MIL-53(Al) bifunctional catalyst exhibited excellent stability and maintained high catalytic activity after five cycles.展开更多
In this work,a Janus-type dual-ligand metal-organic frameworks derived bimetallic(Fe,Co)P nanoparticles embedded carbon nanotube(CNT)skeleton(DLD-Fe Co P@CNT)is presented and synthesized via a facile"co-coordinat...In this work,a Janus-type dual-ligand metal-organic frameworks derived bimetallic(Fe,Co)P nanoparticles embedded carbon nanotube(CNT)skeleton(DLD-Fe Co P@CNT)is presented and synthesized via a facile"co-coordination synthesis"strategy.The DLD-Fe Co P@CNT hybrid shows much better performances for OER and HER with much lower Tafel slope of 39.6(57.1)m V dec-1,an overpotential of 286(166)m V@10 m A cm^(-2)and better stability for OER(HER)in 1 M KOH.Being both cathode and anode for water splitting,it requires only a low voltage of 1.67 V to obtain 10 mA cm^(-2)with nearly 100%faradaic efficiency,which is close to Pt/C//RuO_(2)cell.Density functional theory calculations based on the bimetallic phosphide(Fe_(0.3)Co_(0.7)P)model reveal that,compared with the monometallic Fe P or Co P,the enhanced catalytic activities of Fe_(0.3)Co_(0.7)P is mainly manifested in its free energy of H adsorption(GH*)closer to zero,larger binding strength for H2O and higher electrical conductivity.展开更多
Dimethyl ether(DME),as a promising alternative to diesel fuel and liquefied petroleum gas,has attracted considerable attention in catalysis domain.The catalytic direct synthesis of DME from syngas is an upand-coming r...Dimethyl ether(DME),as a promising alternative to diesel fuel and liquefied petroleum gas,has attracted considerable attention in catalysis domain.The catalytic direct synthesis of DME from syngas is an upand-coming route but remains a challenge.In this work,we firstly prepared a Cu-embedded porous Al_(2)O_(3)bifunctional catalyst(Cu@Al_(2)O_(3)-dp)by filling Cu-1,3,5-benzenetricarboxylate metal–organic framework(Cu-BTC MOF)with Al(OH)_(3) followed by a two-step calcination process(400℃for 4 h and 600℃for1 h),exhibiting excellent catalytic performance for direct synthesis of DME from syngas.Cu@Al_(2)O_(3)-dp catalyst demonstrates much higher CO conversion(25.7%vs.15.4%)and extremely higher DME selectivity(90.4%vs.63.9%)with the increased catalytic stability compared to the supported Cu catalyst on MOF-derived porous Al_(2)O_(3)(Cu/Al_(2)O_(3))prepared by incipient wetness impregnation method,ascribed to the unique embedding-type structure,promoted Cu dispersion and stronger metal-support interaction.This work not only provides an efficient syngas-to-DME catalyst,but also paves a new way for designing highly-efficient core-shell bifunctional catalysts for diverse consecutive reactions.展开更多
Stable and high‐efficiency bifunctional catalysts for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are desired for the practical application of Li‐O_(2)batteries with excellent rate performanc...Stable and high‐efficiency bifunctional catalysts for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are desired for the practical application of Li‐O_(2)batteries with excellent rate performance and cycle stability.Herein,a novel hybrid bifunctional catalyst with carbon nanofibers inlaid with hollow Co_(3)O_(4)nanoparticles and separate active sites for ORR and OER were prepared and applied in Li‐O_(2)batteries.Benefiting from the synergistic effect of unique porous structural features and high electrocatalytic activity of hollow Co3O4 intimately bound to N‐doped carbon nanofibers,the assembled Li‐O_(2)batteries with novel catalyst exhibited high specific capacity,excellent rate capability,and cycle stability up to 150 cycles under a capacity limitation of 500 mAh g^(–1)at a current density of 100 mA g^(–1).The facile synthesis and preliminary results in this work show the as‐prepared catalyst as a promising bifunctional electrocatalyst for applications in metal‐air batteries,fuel cells,and electrocatalysis.展开更多
The development of highly effective metal-zeolite bifunctional catalysts for the hydroisomerization of n-alkanes is a paramount strategy to produce second-generation biofuels with high quality.In this study,polyhexame...The development of highly effective metal-zeolite bifunctional catalysts for the hydroisomerization of n-alkanes is a paramount strategy to produce second-generation biofuels with high quality.In this study,polyhexamethylene biguanide hydrochloride(PHMB)is precisely added to the initial gel to synthesize nanosized ZSM-23 zeolites(Z23-x PH).Due to orientation adsorption and steric hindrance effects of PHMB,each sample of Z23-x PH demonstrates enhanced mesoporosity in comparison with the conventional Z23-C zeolite.Furthermore,the Bronsted acid density of the Z23-x PH samples is also signifi cantly reduced due to a reduction in the distribution of framework Al at T2-T5 sites.The corresponding Pd/23-C and Pd/Z23-x PH bifunctional catalysts with 0.5 wt%Pd loading for n-hexadecane hydroisomerization are prepared by incorporating ZSM-23 zeolites as acid supports.According to the catalytic test results,the suitable addition of PHMB can effectively promote the iso-hexadecane yield.The Pd/Z23-2PH catalyst with an n_(PHMB)/n(_Si)molar ratio of 0.002 demonstrates the highest maximum iso-hexadecane yield of 74.1%at an n-hexadecane conversion of 88.3%.Therefore,the employment of PHMB has provided a simple route for the development of highly effective Pd/ZSM-23 catalysts for n-alkane hydroisomerization.展开更多
Ru@RuO2 core-shell nanorods were successfully synthesized by heat-treating Ru nanorods with air oxidation through an accurate control of the temperature and time. The structure, composition, dimension, and adsorption ...Ru@RuO2 core-shell nanorods were successfully synthesized by heat-treating Ru nanorods with air oxidation through an accurate control of the temperature and time. The structure, composition, dimension, and adsorption property of the core-shell nanorods were well characterized with XRD and TEM. The catalytic activity and stability were electrochemically evaluated with a rotating disk electrode, a rotating ring-disk electrode, and chronopotentiometric methods. The Ru@RuO2 nanorods reveal excellent bifunctional catalytic activity and robust stability for both oxygen evolution reaction(OER) and hydrogen evolution reaction(HER). The overpotentials for OER and HER are 320 m V and 137 m V at the current density of10 m A cm-2, respectively. The catalytic activity of Ru@RuO2 nanorods for OER is 6.5 times higher than that of the state-of-the-art catalyst IrO2 according to the catalytic current density measured at 1.60 V(versus RHE).The catalytic activity of Ru@RuO2 nanorods for HER is comparable to 40%Pt/C by comparing the catalytic current densities at à0.2 V.展开更多
Direct aldol reactions of aldehydes and ketones can proceed smoothly in the presence of a catalytic amount of naphthol/sodium naphtholate(5 mol%) to afford the corresponding products with yields up to 98%.Such a bif...Direct aldol reactions of aldehydes and ketones can proceed smoothly in the presence of a catalytic amount of naphthol/sodium naphtholate(5 mol%) to afford the corresponding products with yields up to 98%.Such a bifunctional catalyst is more moderate than strong acid or base employed in direct aldol reactions.展开更多
Epoxidation is an important chemical process for the production of epoxides,key building blocks in chemical industry.Despite great efforts being made to facilitate this process,it remains a significant challenge to de...Epoxidation is an important chemical process for the production of epoxides,key building blocks in chemical industry.Despite great efforts being made to facilitate this process,it remains a significant challenge to develop cost-effective,environmental-friendly,and selective catalysts.Herein,we reported a highly dispersed Mn supported by g-C_(3)N_(4)(Mn/g-C_(3)N_(4))with Mn loading up to 2.56 wt%.The Mn/g-CN_(4)exhibited satisfied catalytic performance for olefin epoxidation with excellent conversion(91%),high selectivity(93%)as well as outstanding recycling stability.Further analysis revealed the importance of Mn-N structure for the generation of active oxo-containing species and subsequent oxygen atom transfer.Besides,an efficient synthesis of cyclic carbonates from styrene epoxide and CO_(2)has been achieved(88%conversion,89%selectivity)based on the polar Mn-N coordinated characteristics of Mn/g-C_(3)N_(4)catalyst.展开更多
Catalyst for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is at the heart of key renewable energy technologies such as water splitting and rechargeable batteries. But developing a low-cost ...Catalyst for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is at the heart of key renewable energy technologies such as water splitting and rechargeable batteries. But developing a low-cost oxygen electrode catalyst with high activity at low overpotential remains a great challenge. Coconut shells can be utilized as suitable raw material to produce activated carbon for enhanced adsorption capacity, bulk density, and hardness to be used as regenerative fuel cells running ORR and OER. The present work is designed to obtain an alternative to noble metal-based catalysts by synthesizing electroactive N-doped porous carbon from coconut shells;the use of biodegradable raw material through a single-step activation followed by nitrogen doping provides a more economical and environmentally friendly route to produce green catalysts for fuel cell applications. In valorization of biomass for the development of novel catalytic materials, our aim is also to reduce the use of hazardous chemicals. N-doped activated carbon shows promising bifunctional catalyst for ORR and OER as low-cost noble-metal-free and carbon-based oxygen catalysts.展开更多
Metal(oxide)-zeolite bifunctional catalysts have been the subject of considerable attention from researchers in both academic and industry,due to their superior activity and stability in various heterogeneous catalyti...Metal(oxide)-zeolite bifunctional catalysts have been the subject of considerable attention from researchers in both academic and industry,due to their superior activity and stability in various heterogeneous catalytic processes[1–3].Based on the different metal loading sites,these bifunctional catalysts can be categorized as follows:(a)metal species loaded on the outer surface of zeolite crystals,(b)metal species encapsulated within the channels or cavities of zeolites,and(c)metal species incorporated into the zeolite framework(Fig.1).Metal species in type(b)and(c)samples are stabilized by the zeolite frameworks,resulting in excellent thermal and hydrothermal stability during catalytic reactions,especially under harsh conditions,as well as unique shape-selectivity.However,the complex synthesis procedures make large-scale preparation of these catalysts impractical.In contrast,a type(a)sample can be achieved via the simple impregnation;nevertheless,migration of metal species and their aggregation into larger particles often occur during the calcination and reduction processes.展开更多
基金funded by the Master,PhD Scholarship Programme of Vingroup Innovation Foundation(VINIF),code VINIF.2024.TS.035funded by Vietnam National University,Ho Chi Minh City(VNUHCM)under grant number NCM2024-18-01。
文摘In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to significant environmental issues[1].Currently,sustainable biomass resources have attracted much attention as potential substitutes to fossil fuels for producing biofuels and commodity chemicals[2].
基金supported by the National Natural Science Foundation of China(NSFC,Nos.21901018,21971024,22271021)the Natural Science Foundation and Education Department of Liaoning province(Nos.2022-MS-373,2021-MS-312,LJ2020008).
文摘The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human health.Therefore,it is very important to develop a con-venient and effective method to detect and degrade phenolic compounds.Herein,we report a new keggin-type polyoxometallate-based metal-organic complex self-assembled under solvothermal condition,{[Cu(dap)(3-PA)]4(SiW_(12)O_(40))(H_(2)O)_(2)}·2H_(2)O(1,dap=1,2-diaminopropane,3-HPA=3-pyridineacrylic acid).1 shows an interesting 1D ladder-like structure.As a bifunctional catalyst,1 can be employed as a colori-metric sensor toward phenol with the relatively low detection limit(LOD)of 0.36μmol/L(S/N=3)in the wide range(0.001-0.1 mmol/L).The title colorimetric sensor is applied to determine phenol in various water environment with good recoveries ranging from 95%-105%.In addition,1 also exhibits excellent photocatalytic degradation toward phenol under visible light with the highest removal efficiency at 96%for 100 min and wide pH universality.The selectivity,stability and reliability of the detection of 1 towards phenol,as well as the detection for 4-chlorophenol,o-cresol,4-nitrophenol and phloroglucinol were stud-ied.Furthermore,the photocatalytic reaction kinetics and the mechanisms of photodegradation of phenol were also investigated in detail.
基金the support received from the National Natural Science Foundation of China(Grant No.22372012,22261160640,and 22002009)the Natural Science Foundation of Hunan Province(Grant No.2023JJ20037 and 2021JJ40565)the Scientific Research Project of Hunan Provincial Department of Education(Grant No.22B0293)
文摘The electrochemical coupling of biomass oxidation and nitrogen conversion presents a potential strategy for high value-added chemicals and nitrogen cycling.Herein,in this work,CuO/Co_(3)O_(4)with heterogeneous interface is successfully constructed as a bifunctional catalyst for the electrooxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid and the electroreduction of nitrate to ammonia(NH_(3)).The open-circuit potential spontaneous experiment shows that more 5-hydroxymethylfurfural molecules are adsorbed in the Helmholtz layer of the CuO/Co_(3)O_(4)composite,which certifies that the CuO/Co_(3)O_(4)heterostructure is conducive to the kinetic adsorption of 5-hydroxymethylfurfural.In situ electrochemical impedance spectroscopy further shows that CuO/Co_(3)O_(4)has faster reaction kinetics and lower reaction potential in oxygen evolution reaction and 5-hydroxymethylfurfural electrocatalytic oxidation.Moreover,CuO/Co_(3)O_(4)also has a good reduction effect on NO_(3)^(-).The ex-situ Raman spectroscopy shows that under the reduction potential,the metal oxide is reduced,and the generated Cu_(2)O can be used as a new active site for the reaction to promote the electrocatalytic conversion of NO_(3)^(-)to NH_(3) synthesis.This work provides valuable guidance for the synthesis of value-added chemicals by 5-hydroxymethylfurfural electrocatalytic oxidation coupled with NO_(3)^(-)while efficiently producing NH_(3).
基金the National Key Research and Development Program of China (No. 2020YFA0211004)Key Grant of Nation Science Funding of China (No. 22236005)+5 种基金Nation Science Funding of China (No. 22376141)Ministry of Education of China (No. PCSIRT_IRT_16R49)“111” Innovation and Talent Recruitment Base (D18020)Shanghai Government (No. 20ZR1440700)Shanghai Engineering Research Center of Green Energy Chemical Engineering (No. 18DZ2254200)Scientific and Technological Innovation Team for Green Catalysis and Energy Materialien Yunnan Institutions of Higher Learning, and Surface project of Yunnan Province science and technology Department (No. 20210 A070001-050).
文摘Deep degradation of organic pollutants by sunlight-induced coupled photocatalytic and Fenton (photo-Fenton) reactions is of immense importance for water purification. In this work, we report a novel bifunctional catalyst (Fe-PEI-CN) by codoping graphitic carbon nitride (CN) with polyethyleneimine ethoxylated (PEI) and Fe species, which demonstrated high activity during p-chlorophenol (p-ClPhOH) degradation via H_(2)O_(2) from the photocatalytic process. The relationship between the catalytic efficiency and the structure was explored using diff erent characterization methods. The Fe modification of CN was achieved through Fe-N coordination, which ensured high dispersion of Fe species and strong stability against leaching during liquid- phase reactions. The Fe modification initiated the Fenton reaction by activating H_(2)O_(2) into ·OH radicals for deep degradation of p-ClPhOH. In addition, it eff ectively promoted light absorption and photoelectron-hole (e-h ^(+) ) separation, corresponding to improved photocatalytic activity. On the other hand, PEI could significantly improve the ability of CN to generate H_(2)O_(2) through visible light photocatalysis. The maximum H_(2)O_(2) yield reached up to 102.6 μmol/L, which was 22 times higher than that of primitive CN. The cooperation of photocatalysis and the self-Fenton reaction has led to high-activity mineralizing organic pollutants with strong durability, indicating good potential for practical application in wastewater treatment.
基金the financial support from the CNOOC CCUS Major Project(Project Number KJGG-2022-12-CCUS-030402).
文摘The selective production of gasoline from syngas is an important technology in the current stage of energy transformation and upgrading.The product distribution of traditional Fischer-Tropsch synthesis follows the Anderson-Schulz-Flory(ASF)distribution law,and breaking through the distribution limitations to produce more gasoline components depends largely on the design and development of high-performance catalysts.In this paper,the recent research progress of bifunctional catalysts for gasoline production from syngas with high selectivity is summarized.This includes core-shell structure catalyst,microporous zeolite supported catalyst,mesoporous zeolite supported catalyst,metal oxide-zeolite relay catalyst.Moreover,the reaction mechanisms are summarized.The future prospects of catalysts for the high-selectivity synthesis of gasoline from syngas is also discussed.The current review will provide insights into the bifunctional catalysts for one-step syngas conversion to gasoline.
基金supported by the National Key Technologies R&D Program of China(2011BAC01B03)the Natural Science Foundation of Yunnan Province(2013FZ035)support by Kunming University of Science and Technology through the Fund for Testingand Analyzing(No.2010213)
文摘A series of CuO-ZnO-Al2O3-La2O3/HZSM-5 biftmctional catalysts with various La loadings for dimethyl ether (DME) directly synthesized from CO2 hydrogenation were prepared. The catalysts were characterized with N2 adsorption-desorption, X-ray diffraction (XRD), H2 temperature-programmed reduction (H2-TPR), NH3 temperature-programmed desorption (NH3-TPD) and N2O titration techniques, and tested for the synthesis of DME directly from CO2 hydrogenation in a fixed-bed reactor. The results showed that the reducibility, dispersion ofbifunctional catalysts were strongly dependent on the addition of La. With the addition of appropri- ate amount of La, the crystaUite size of CuO was decreased and the dispersion of Cu on the surface was enhanced, which resulted in the increased conversion of CO2. It was also found that the selectivity to DME was related to the intensity and amount of strong acid site on the catalyst surface. The presence of La favored the production of DME, and the optimum catalytic activity was obtained when the amount of La was 2.0 wt.%.
基金financial support from the National Key Research&Development Program of China(2018YFB0604901)the National Natural Science Foundation of China(21706210)the Key Research&Development Program of Shaanxi Province(2020ZDLGY11-06)。
文摘A series of ZnO-ZrO_(2) solid solutions with different Zn contents were synthesized by the urea coprecipitation method,which were coupled with H-ZSM-5 zeolite to form bifunctional catalysts.As a new benzene alkylation reagent,syngas was used instead of methanol to realize the efficient conversion of syngas and benzene into toluene and xylene.A suitable ratio of ZnO-ZrO_(2) led to the significant improvement in the catalytic performance,and a suitable amount of acid helped to increase the selectivity of toluene/xylene and reduce the selectivity of the by-products ethylbenzene and C^(9+) aromatics.The highest benzene conversion of 89.2%and toluene/xylene selectivity of 88.7%were achieved over 10%ZnO-ZrO_(2)&H-ZSM-5(Si/Al=23)at a pressure of 3 MPa and a temperature of 450℃.In addition,the effect of the zeolite framework structure on product distribution was examined.Similar to the molecular dynamics of aromatic hydrocarbons,H-ZSM-5 zeolites comprise 10-membered-ring pores,which are beneficial to the activation of benzene;hence,the conversion of benzene is higher.H-ZSM-35 and HMOR zeolites exhibited small eight-membered-ring channels,which were not conducive to the passage of benzene;hence,the by-product ethylbenzene exhibits a higher selectivity.The distance between the active centers of the bifunctional catalysts was the main factor affecting the catalytic performance,and the powder mixing method was more conducive to the conversion of syngas and benzene.
基金supported by the Shandong Provincial Key research and development plan,China(Grant No.2017GGX40119)the Shandong Provincial Natural Science Foundation,China(Grant No.ZR2019MB033,ZR2015BM002)the Program of the Qingdao Key Lab of solar energy utilization and energy storage technology(Grant No.QDKLSE201602)。
文摘The rational design and development of cost-effective,high-performance,and stable bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalysts are essential for rechargeable zinc-air batteries.Herein,a novel FeCo composite composed of alloy nanoparticles embedded in an N,S dual-doped carbon matrix(FeCo/NSC)was prepared via one-step carbonization of amphiphilic dodecanethiol-metal salts wrapped in carbon nitride(C_(3)N_(4)).The compact combination of dual metalalloys and dual-doped carbon endowed the composite with the active sites for the ORR and OER,achieving efficient electrical transmission and highly efficient bifunctional catalytic performance.The obtained FeCo-1/NSC catalyst exhibited excellent electrocatalytic activity with a half-wave potential of 0.82 V(vs.RHE)for the ORR and a low overpotential of 0.325 V at 10 mA cm^(-2) for the OER.The liquid Zn-air battery with FeCo-1/NSC as an air electrode displayed excellent charge-discharge performance,high power density,and robust charge-discharge stability for 150 h compared to the 20%Pt/C+RuO_(2) counterpart.Furthermore,the FeCo-1/NSC-based flexible solid-state Zn-air battery exhibited a higher power density and good charge-discharge stability over 10 h of operation.Thus,a promising strategy for bifunctional electrocatalyst development as part of rechargeable and wearable Zn-air batteries was provided.
基金the financial support from the National Natural Science Foundation of China(22005273,21825106 and 21671175)the Natural Science Foundation of Henan Province(222300420258)+3 种基金the Scientific and Technological Research Project in Henan Province(222102240065 and 212102210647)the Key scientific research projects of colleges and universities in Henan Province(No.22A530006)the Natural Science Foundation of Jiangsu Province(BK20220598)the Program for Science&Technology Innovative Research Team in University of Henan Province(20IRTSTHN007)。
文摘The utilization of non-noble metal catalysts with robust and highly efficient electrocatalytic activity for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)are extremely important for the large-scale implementation of renewable energy devices.Integration of bifunctional electrocatalysts on both anode and cathode electrodes remains a significant challenge.Herein,we report on a novel and facile strategy to construct the ordered and aligned MoS_(2)nanosheet-encapsulated metal–organic frameworks(MOFs)derived hollow CoS polyhedron,in-situ grown on a nickel foam(NF).The starfish-like MoS_(2)/CoS/NF heterojunctions were formed due to the ordered growth of the material caused by NF substrate.The optimized 2-MoS_(2)/CoS/NF heterojunction exhibits robust bifunctional electrocatalytic activity with a low overpotential of 67 and 207 m V toward the HER and OER at 10 mA cm^(-2),and the long-term stability,which exceeds most of the reported bifunctional electrocatalysts.Such high electrocatalytic performance arises due to the synergistic effect between the MoS_(2)and CoS phases across the interface,the abundant active sites,as well as the hierarchical pore framework,which collectively enhance the mass and electron transfer during the reactions.The work provides a promising approach to fabricating bifunctional catalysts with custom-designed heterojunctions and remarkable performance for applications in electrochemical energy devices and related areas.
基金support from the National Key Research and Development Program of China (2019YFA0705700)the National Natural Science Foundation of China (52072205)+1 种基金the start-up funds of Tsinghua Shenzhen International Graduate Schoosupported by the China Postdoctoral Science Foundation(2020M680542)。
文摘Zinc-air batteries(ZABs) with high energy density and safety are promising as next-generation energy storage systems, while their applications are severely hindered by the sluggish reaction kinetic of air cathodes. Developing a bifunctional catalyst with high activity and durability is an effective strategy to address the above challenges. Herein, a Co_(3)O_(4)/Mn_(3)O_(4) nanohybrid with heterointerfaces is designed as advanced cathode catalyst for ZABs. Density functional theory calculations show the heterogeneous interface between Co_(3)O_(4)/Mn_(3)O_(4) can improve the dynamics of carrier transport and thus enhancing the catalytic activity and durability. The Co_(3)O_(4)/Mn_(3)O_(4) catalyst anchored on reduced graphene oxide(rGO)exhibits high oxygen reduction reaction(ORR) activity with a half-wave potential of 0.86 V, and excellent oxygen evolution reaction(OER) activity with the potential of 1.59 V at 10 mA cm^(-2) , which are comparable to the commercial noble metal catalysts. The improved ORR/OER catalytic activity is ascribed to the synergistic effect of heterointerfaces between Co_(3)O_(4) and Mn_(3)O_(4)as well as the improved conductivity and contact area of oxygen/catalysts/electrolytes three-phase interface by r GO. Furthermore, a home-made ZAB based on Co_(3)O_(4)/Mn_(3)O_(4)/r GO shows a high open circuit voltage of 1.54 V, a large power density of 194.6 mW cm^(-2) and good long-term cycling stability of nearly 400 h at 5 mA cm^(-2) , which affords a promising bifunctional oxygen catalyst for rechargeable ZABs.
基金Financial support received from the National Natural Science Foundation of China(Grant Nos.21573015,21872004)
文摘A series of Pd/MIL-53(Al) heterogeneous bifunctional catalysts with di erent Pd contents were prepared by an impregnation method. The prepared metal–organic frameworks MIL-53(Al) and catalysts were characterized by XRD, SEM, HRTEM,FT-IR and N2 adsorption/desorption techniques. The results showed that MIL-53(Al) was synthesized successfully, and the structure was unchanged during and after the preparation of the catalysts. The Pd nanoparticles(NPs) with an average particle size of 4.6 nm were uniformly dispersed on the MIL-53(Al). The catalyst exhibited good catalytic activity in the selective oxidation of liquid methanol to methyl formate. Under the conditions of 150 °C, 2 MPa O2 and solvent-free for5 h, the conversion of methanol could reach 60.3%, and the selectivity of methyl formate was up to 62.2%. In addition, the Pd/MIL-53(Al) bifunctional catalyst exhibited excellent stability and maintained high catalytic activity after five cycles.
基金the National Natural Science Foundation of China(No.21773024)the Sichuan Science and Technology Program(No.20YYJC3786)+1 种基金the Reformation and Development Funds for Local Region Universities from China Government in 2020(No.ZCKJ 2020-11)the Natural Science Foundation of the Tibet Autonomous Region(No.2016ZR-TU-10)。
文摘In this work,a Janus-type dual-ligand metal-organic frameworks derived bimetallic(Fe,Co)P nanoparticles embedded carbon nanotube(CNT)skeleton(DLD-Fe Co P@CNT)is presented and synthesized via a facile"co-coordination synthesis"strategy.The DLD-Fe Co P@CNT hybrid shows much better performances for OER and HER with much lower Tafel slope of 39.6(57.1)m V dec-1,an overpotential of 286(166)m V@10 m A cm^(-2)and better stability for OER(HER)in 1 M KOH.Being both cathode and anode for water splitting,it requires only a low voltage of 1.67 V to obtain 10 mA cm^(-2)with nearly 100%faradaic efficiency,which is close to Pt/C//RuO_(2)cell.Density functional theory calculations based on the bimetallic phosphide(Fe_(0.3)Co_(0.7)P)model reveal that,compared with the monometallic Fe P or Co P,the enhanced catalytic activities of Fe_(0.3)Co_(0.7)P is mainly manifested in its free energy of H adsorption(GH*)closer to zero,larger binding strength for H2O and higher electrical conductivity.
基金the National Natural Science Foundation of China(No.U1610104)Liaoning Revitalization Talents Program(No.XLYC1907053,China)CAS Youth Innovation Promotion Association(No.2018220,China)。
文摘Dimethyl ether(DME),as a promising alternative to diesel fuel and liquefied petroleum gas,has attracted considerable attention in catalysis domain.The catalytic direct synthesis of DME from syngas is an upand-coming route but remains a challenge.In this work,we firstly prepared a Cu-embedded porous Al_(2)O_(3)bifunctional catalyst(Cu@Al_(2)O_(3)-dp)by filling Cu-1,3,5-benzenetricarboxylate metal–organic framework(Cu-BTC MOF)with Al(OH)_(3) followed by a two-step calcination process(400℃for 4 h and 600℃for1 h),exhibiting excellent catalytic performance for direct synthesis of DME from syngas.Cu@Al_(2)O_(3)-dp catalyst demonstrates much higher CO conversion(25.7%vs.15.4%)and extremely higher DME selectivity(90.4%vs.63.9%)with the increased catalytic stability compared to the supported Cu catalyst on MOF-derived porous Al_(2)O_(3)(Cu/Al_(2)O_(3))prepared by incipient wetness impregnation method,ascribed to the unique embedding-type structure,promoted Cu dispersion and stronger metal-support interaction.This work not only provides an efficient syngas-to-DME catalyst,but also paves a new way for designing highly-efficient core-shell bifunctional catalysts for diverse consecutive reactions.
文摘Stable and high‐efficiency bifunctional catalysts for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are desired for the practical application of Li‐O_(2)batteries with excellent rate performance and cycle stability.Herein,a novel hybrid bifunctional catalyst with carbon nanofibers inlaid with hollow Co_(3)O_(4)nanoparticles and separate active sites for ORR and OER were prepared and applied in Li‐O_(2)batteries.Benefiting from the synergistic effect of unique porous structural features and high electrocatalytic activity of hollow Co3O4 intimately bound to N‐doped carbon nanofibers,the assembled Li‐O_(2)batteries with novel catalyst exhibited high specific capacity,excellent rate capability,and cycle stability up to 150 cycles under a capacity limitation of 500 mAh g^(–1)at a current density of 100 mA g^(–1).The facile synthesis and preliminary results in this work show the as‐prepared catalyst as a promising bifunctional electrocatalyst for applications in metal‐air batteries,fuel cells,and electrocatalysis.
基金funded by the National Key Research and Development Project,Intergovernmental International Science and Technology Innovation Cooperation Key Project(No.2018YFE0108800)National Natural Science Foundation of China(No.22278115)Heilongjiang Province Natural Science Foundation(No.YQ2021B010).
文摘The development of highly effective metal-zeolite bifunctional catalysts for the hydroisomerization of n-alkanes is a paramount strategy to produce second-generation biofuels with high quality.In this study,polyhexamethylene biguanide hydrochloride(PHMB)is precisely added to the initial gel to synthesize nanosized ZSM-23 zeolites(Z23-x PH).Due to orientation adsorption and steric hindrance effects of PHMB,each sample of Z23-x PH demonstrates enhanced mesoporosity in comparison with the conventional Z23-C zeolite.Furthermore,the Bronsted acid density of the Z23-x PH samples is also signifi cantly reduced due to a reduction in the distribution of framework Al at T2-T5 sites.The corresponding Pd/23-C and Pd/Z23-x PH bifunctional catalysts with 0.5 wt%Pd loading for n-hexadecane hydroisomerization are prepared by incorporating ZSM-23 zeolites as acid supports.According to the catalytic test results,the suitable addition of PHMB can effectively promote the iso-hexadecane yield.The Pd/Z23-2PH catalyst with an n_(PHMB)/n(_Si)molar ratio of 0.002 demonstrates the highest maximum iso-hexadecane yield of 74.1%at an n-hexadecane conversion of 88.3%.Therefore,the employment of PHMB has provided a simple route for the development of highly effective Pd/ZSM-23 catalysts for n-alkane hydroisomerization.
基金the U.S.Department of the ArmyU.S.Army Materiel Command for supporting this work
文摘Ru@RuO2 core-shell nanorods were successfully synthesized by heat-treating Ru nanorods with air oxidation through an accurate control of the temperature and time. The structure, composition, dimension, and adsorption property of the core-shell nanorods were well characterized with XRD and TEM. The catalytic activity and stability were electrochemically evaluated with a rotating disk electrode, a rotating ring-disk electrode, and chronopotentiometric methods. The Ru@RuO2 nanorods reveal excellent bifunctional catalytic activity and robust stability for both oxygen evolution reaction(OER) and hydrogen evolution reaction(HER). The overpotentials for OER and HER are 320 m V and 137 m V at the current density of10 m A cm-2, respectively. The catalytic activity of Ru@RuO2 nanorods for OER is 6.5 times higher than that of the state-of-the-art catalyst IrO2 according to the catalytic current density measured at 1.60 V(versus RHE).The catalytic activity of Ru@RuO2 nanorods for HER is comparable to 40%Pt/C by comparing the catalytic current densities at à0.2 V.
基金supported by the Natural Science Foundation of China(Nos.20872120 and 20572087)the Municipal Science Foundation of Chongqing City(No.2003-8118)+1 种基金the Ministry of Education,PR of China(No.106141)the Fundamental Research Funds for the Central Universities
文摘Direct aldol reactions of aldehydes and ketones can proceed smoothly in the presence of a catalytic amount of naphthol/sodium naphtholate(5 mol%) to afford the corresponding products with yields up to 98%.Such a bifunctional catalyst is more moderate than strong acid or base employed in direct aldol reactions.
基金financial supports from the National Natural Science Foundation of China(Nos.216330133and 22102197)Jiangsu Province Natural Science Foundation(No.BK20211096)the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing(Yantai,No.AMGM2021F07).
文摘Epoxidation is an important chemical process for the production of epoxides,key building blocks in chemical industry.Despite great efforts being made to facilitate this process,it remains a significant challenge to develop cost-effective,environmental-friendly,and selective catalysts.Herein,we reported a highly dispersed Mn supported by g-C_(3)N_(4)(Mn/g-C_(3)N_(4))with Mn loading up to 2.56 wt%.The Mn/g-CN_(4)exhibited satisfied catalytic performance for olefin epoxidation with excellent conversion(91%),high selectivity(93%)as well as outstanding recycling stability.Further analysis revealed the importance of Mn-N structure for the generation of active oxo-containing species and subsequent oxygen atom transfer.Besides,an efficient synthesis of cyclic carbonates from styrene epoxide and CO_(2)has been achieved(88%conversion,89%selectivity)based on the polar Mn-N coordinated characteristics of Mn/g-C_(3)N_(4)catalyst.
文摘Catalyst for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is at the heart of key renewable energy technologies such as water splitting and rechargeable batteries. But developing a low-cost oxygen electrode catalyst with high activity at low overpotential remains a great challenge. Coconut shells can be utilized as suitable raw material to produce activated carbon for enhanced adsorption capacity, bulk density, and hardness to be used as regenerative fuel cells running ORR and OER. The present work is designed to obtain an alternative to noble metal-based catalysts by synthesizing electroactive N-doped porous carbon from coconut shells;the use of biodegradable raw material through a single-step activation followed by nitrogen doping provides a more economical and environmentally friendly route to produce green catalysts for fuel cell applications. In valorization of biomass for the development of novel catalytic materials, our aim is also to reduce the use of hazardous chemicals. N-doped activated carbon shows promising bifunctional catalyst for ORR and OER as low-cost noble-metal-free and carbon-based oxygen catalysts.
基金financially supported by the National Key R&D Program of China(2024YFE0101100)the National Natural Science Foundation of China(22475112,22305132,22305155)+1 种基金the China Postdoctoral Science Foundation(2023M732323)the Postdoctoral Fellowship Program of CPSF(GZC20231679).
文摘Metal(oxide)-zeolite bifunctional catalysts have been the subject of considerable attention from researchers in both academic and industry,due to their superior activity and stability in various heterogeneous catalytic processes[1–3].Based on the different metal loading sites,these bifunctional catalysts can be categorized as follows:(a)metal species loaded on the outer surface of zeolite crystals,(b)metal species encapsulated within the channels or cavities of zeolites,and(c)metal species incorporated into the zeolite framework(Fig.1).Metal species in type(b)and(c)samples are stabilized by the zeolite frameworks,resulting in excellent thermal and hydrothermal stability during catalytic reactions,especially under harsh conditions,as well as unique shape-selectivity.However,the complex synthesis procedures make large-scale preparation of these catalysts impractical.In contrast,a type(a)sample can be achieved via the simple impregnation;nevertheless,migration of metal species and their aggregation into larger particles often occur during the calcination and reduction processes.