The reaction between 3-substituted-4-hydroxy-2H-1.2-be 1.1-dioxides and phenyl isocyanate in the presence of different equivalents of strong base NaH has been studied. The structures of new derivatives were characteri...The reaction between 3-substituted-4-hydroxy-2H-1.2-be 1.1-dioxides and phenyl isocyanate in the presence of different equivalents of strong base NaH has been studied. The structures of new derivatives were characterized by 1H NMR. IR. elementary analysis and FeCl3 test.展开更多
In order to promote our understanding on electronic structure of actinide dioxides, we construct a tight-binding model composed of actinide 5f and oxygen 2p electrons, which is called f-p model. After the diagonalizat...In order to promote our understanding on electronic structure of actinide dioxides, we construct a tight-binding model composed of actinide 5f and oxygen 2p electrons, which is called f-p model. After the diagonalization of the f-p model, we compare the eigen-energies in the first Brillouin zone with the results of relativistic band-structure calculations. Here we emphasize a key role of f-p hybridization in order to understand the electronic structure of actinide dioxides. In particular, it is found that the position of energy levels of Г7 and Г8 states determined from crystalline electric field (CEF) potentials depends on the f-p hybridization. We investiagte the values of the Slater-Koster integrals for f-p hybridization, (fpσ) and (fpπ), which reproduce simultaneously the local CEF states and the band-structure calculation results. Then, we find that the absolute value of (fpπ) should be small in comparison with (fpσ) = 1 eV. The small value of |(fpπ)| is consistent with the condition to obtain the octupole ordering in the previous analysis of the f-p model.展开更多
A type of high visible-light active titanium oxinitride(TiO2-xNx)powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric f...A type of high visible-light active titanium oxinitride(TiO2-xNx)powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures.The hydrated titanium dioxide was synthesized as the precursor of TiO2-xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white.The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied.The visible-light activity and photocatalysis capability of the powder were also investigated.展开更多
Lamellar compounds such as the disulfides of molybdenum and tungsten are widely used as additives in lubricant oils or as solid lubricants in aerospace industries.The dioxides of these two transition metals have ident...Lamellar compounds such as the disulfides of molybdenum and tungsten are widely used as additives in lubricant oils or as solid lubricants in aerospace industries.The dioxides of these two transition metals have identical microstructures with those of the disulfides.The differences in the lubrication behaviors of disulfide and dioxides were investigated theoretically.Tungsten dioxide and molybdenum dioxide exhibit higher bond strengths at the interface and lower interlayer interactions than those of the disulfides which indicates their superlubricity.Furthermore,the topography of the electron density of the single layer nanostructure determined their sliding potential barrier;the dioxides showed a weaker electronic cloud distribution between the two neighboring oxygen atoms,which facilitated the oxygen atoms of the counterpart to go through.For commensurate friction,the dioxides exhibited nearly the same value of friction work,and same was the case for the disulfides.The lower positive value of friction work for the dioxides confirmed their improved lubricity than the disulfides and the higher mechanical strength of the bulk dioxides demonstrated that they are excellent solid lubricants in vacuum.展开更多
Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prep...Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol.展开更多
Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting t...Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting two greenhouse gases(methane and carbon dioxide)into syngas and its promising industrial applications.Nickel(Ni)-based catalysts,with high catalytic activity,low cost,and abundant resources,are considered ideal candidates for industrial applications.In this article,three reaction kinetic models were briefly introduced,namely the Power-Law(PL)model,the Eley-Rideal(ER)model,and the Langmuir-Hinshelwood-Hougen-Watson(LHHW)model.Based on the LHHW model,the reaction kinetics and mechanisms of different catalytic systems were systematically discussed,including the properties of supports,the doping of noble metals and transition metals,the role of promoters,and the influence of the geometric and electronic structures of Ni on the reaction mechanism.Furthermore,the kinetics of carbon deposition and elimination on various catalysts were analyzed.Based on the reaction rate expressions for carbon elimination,the reasons for the high activity of transition metal iron(Fe)-doped catalysts and core-shell structured catalysts in carbon elimination were explained.Based on the detailed collation and comparative analysis of the reaction mechanisms and kinetic characteristics across diverse Ni-based catalytic systems,a theoretical guidance for the designing of high-performance catalysts was provided in this work.展开更多
The reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanate under different equivalents of strong base NaH was studied. Seventeen of new derivatives were obtained whose structures we...The reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanate under different equivalents of strong base NaH was studied. Seventeen of new derivatives were obtained whose structures were characterized by H-1 NMR, IR, MS, elementary analysis and FeCl3 test.展开更多
As the carrier of charge storage,the electrode determines the efficiency of the energy conversion reaction between the battery and the substance.However,with the continuous development of scientific research,electrode...As the carrier of charge storage,the electrode determines the efficiency of the energy conversion reaction between the battery and the substance.However,with the continuous development of scientific research,electrode preparation is still facing complex technical problems,and it is difficult to achieve a balance in performance,cost,and technology.Based on the ion dissolution and deposition behavior of Mn^(2+)/MnO_(2) and Al^(3+)/Al,a novel cathode-free aqueous ion dissolution/deposition battery is designed,which can contribute 15 mAh at 16 cm^(2) in a voltage window of 0.5-1.8 V.The charge storage and the attenuation mechanism are systematically investigated.The battery model with compensable electrolyte was constructed,and the cycle characteristics of the cathode-free aqueous ion dissolution/deposition battery were optimized,which could achieve 1000 h continuous operation.This system provides a low-cost and high-safety solution for future high-energy density and large-scale energy storage.Future research will focus on optimizing electrolytes,controlling deposition morphology,and improving interface stability to further promote the commercialization of cathode-free batteries.展开更多
To enhance the visible light response of titanium dioxide(TiO_(2)),titanium carbide(TiC)nanoparticles(NPs)were thermally treated in carbon powder,effectively overcoming the challenges associated with conventional dopi...To enhance the visible light response of titanium dioxide(TiO_(2)),titanium carbide(TiC)nanoparticles(NPs)were thermally treated in carbon powder,effectively overcoming the challenges associated with conventional doping methods.During the treatment,a TiO_(2)thin shell with oxygen vacancies(OVs)formed around the TiC NPs,creating a shell-core structure S-scheme photocatalyst.Transmission electron microscopy(TEM)and ultraviolet-visible(UV-vis)spectroscopy confirmed the successful formation of the TiO_(2)shell.By optimizing the shell thickness,the TiO_(2)-TiC shell-core structure achieved an ideal shell-core ratio,resulting in strong visible light absorption(400-800 nm),and the degradation rate constant of Rhodamine B(RhB)of sample cHT500 reached 0.0687 min^(−1),which is 20.8times higher than that of pristine TiO_(2)(0.0033 min^(−1))under visible-light irradiation.In addition,cytocompatibility tests showed that sample cHT500 exhibits favorable cell viability,which is comparable to that of TiO_(2)nanoparticles,and thus remarkably mitigates the poor biocompatibility inherent to TiC,making them promising candidates for biomedical and photocatalytic applications.展开更多
Efficiency of C-C bond coupling in highly inert CO_(2)is relatively low,which severely limits its efficient conversion to acetate.Here,we successfully developed a highly stable NF@CoMn_(2)O_(4)@Cu_(2)O-Ag bimetallic a...Efficiency of C-C bond coupling in highly inert CO_(2)is relatively low,which severely limits its efficient conversion to acetate.Here,we successfully developed a highly stable NF@CoMn_(2)O_(4)@Cu_(2)O-Ag bimetallic active site catalyst by anchoring Ag on the Cu_(2)O surface.In this catalyst,the Co^(3+)/Mn^(3+)-Mn^(4+)removes excess electrons from the Cu+sites via strong electronic interactions,preventing the reduction of Cu_(2)O to metallic Cu^(0),which ensures the NF@CoMn_(2)O_(4)@Cu_(2)O-Ag exhibits a high resistance to deactivation.The Cu+active sites of NF@CoMn_(2)O_(4)@Cu_(2)O-Ag efficiently electroreduce CO_(2)to the*COatop intermediate,while the Ag active sites efficiently electroreduce CO_(2)to the^(*)CO_(bridge)intermediate.The proximity of Cu+/Ag bimetallic sites shortens the distance for C-C bond coupling between the*COatop and^(*)CO_(bridge)intermediates,facilitating the efficient electrocatalytic coupling of CO_(2)to synthesize acetate.DFT analysis indicates that theΔG required for C-C bond coupling on the short-distance Cu+/Ag bimetallic sites of NF@CoMn_(2)O_(4)@Cu_(2)O-Ag is significantly lower than that of NF@CoMn_(2)O_(4)@Cu_(2)O,enabling a high Faradaic efficiency of 64.97%for acetate production at-0.3 V vs.RHE.This study provides an effective strategy for the rational design of synergistic catalysis between heterometallic catalytic sites to efficiently achieve C-C coupling for the synthesis of C2+products.展开更多
Artificial synthesis is an environment friendly photocatalytic strategy to converse carbon dioxide(CO_(2))into useful chemicals.However,water(H_(2)O)splitting,producing(hydrogen)H_(2) strongly,is always a competitive ...Artificial synthesis is an environment friendly photocatalytic strategy to converse carbon dioxide(CO_(2))into useful chemicals.However,water(H_(2)O)splitting,producing(hydrogen)H_(2) strongly,is always a competitive reaction to CO_(2) conversion.Therefore,proper cocatalysts are generally needed to enhance CO_(2) conversion but suppress H_(2) production.In this work,zinc/gallium(Zn/Ga)dual co-catalysts consisting of Zn0 and amorphous ZnGa_(2)O_(4) species were found to selectively produce carbon monoxide(CO)during the photocatalytic conversion of carbon dioxide(CO_(2))using water(H_(2)O)as an electron donor over photocatalysts such as NaTaO_(3),Ga_(2)O_(3),and ZnGa_(2)O_(4),and in the electrochemical reduction of CO_(2) over Zn0 electrodes.It is considered that there are two effects associated with the Zn/Ga dual co-catalysts:(1)a galvanic cell effect between Zn0 and amorphous ZnGa_(2)O_(4),and(2)a Z-scheme effect in NaTaO_(3)/Zn0/amorphous ZnGa_(2)O_(4).The coupling of these two effects favored the active and selective evolution of CO during the photocatalytic conversion of CO_(2) by H_(2)O.In the case of Ga_(2)O_(3) photocatalyst,480.8μmol/h of CO was produced with the presence of Zn/Ga dual cocatalysts.Moreover,the Zn/Ga dual cocatalysts universally worked in the electrochemical reduction of CO_(2).The partial current toward CO_(2) conversion was increased from 2.6 to 6.6 mA/cm,and the selectivity toward CO was promoted to from 46.4%to 74.2%.展开更多
Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic de...Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic design of“Trunk-Branch-Leaf”strategy is proposed to prepare the ultrathin edge-riched Zn-ene“leaves”with a thickness of~2.5 nm,adjacent Zn-ene cross-linked with each other,which are supported by copper nanoneedle“branches”on copper mesh“trunks,”named as Zn-ene/Cu-CM.The resulting superstructure enables the formation of an interconnected network and multiple channels,which can be used as an electrocatalytic CO_(2) reduction reaction(CO_(2)RR)electrode to allow a fast charge and mass transfer as well as a large electrolyte reservoir.By virtue of the distinctive structure,the obtained Zn-ene/Cu-CM electrode exhibits excellent selectivity and activity toward CO production with a maximum Faradaic efficiency of 91.3%and incredible partial current density up to 40 mA cm^(−2),outperforming most of the state-of-the-art Zn-based electrodes for CO_(2) reduction.The phenolphthalein color probe combined with in situ attenuated total reflection-infrared spectroscopy uncovered the formation of the localized pseudo-alkaline microenvironment at the interface of the Zn-ene/Cu-CM electrode.Theoretical calculations confirmed that the localized pH as the origin is responsible for the adsorption of CO_(2) at the interface and the generation of *COOH and *CO intermediates.This study offers valuable insights into developing efficient electrodes through synergistic regulation of reaction microenvironments and active sites,thereby facilitating the electrolysis of practical CO_(2) conversion.展开更多
Photocatalytic carbon dioxide reduction reaction(CO_(2)RR)is a carbon-neutral strategy to address global energy use and its impact on climate.Metal oxide and metal chalcogenide catalysts are the most investigated cata...Photocatalytic carbon dioxide reduction reaction(CO_(2)RR)is a carbon-neutral strategy to address global energy use and its impact on climate.Metal oxide and metal chalcogenide catalysts are the most investigated catalysts for photocatalytic CO_(2)RR.Unfortunately,low CO_(2)adsorption ability and limited active sites of metal oxide and metal chalcogenide catalysts for CO_(2)RR make them less competitive compared to their industrial counterparts.Inspired by applications of porphyrin-based metal-organic framework(MOF)catalysts for hydrogen evolution and photodynamic therapy,the investigations of these porphyrin-based MOFs,including pristine and composite porphyrin-based MOFs in photocatalytic CO_(2)RR,have attracted significant attention in the last five years due to their excellent CO_(2)adsorption capacities,high porosity,high stability,exceptional optoelectronic properties,and multi-functionality.However,due to the difference in photocatalytic CO_(2)RR,several critical issues need to be addressed to achieve the rational design of advanced porphyrin-based MOF photocatalysts to improve activity,selectivity,and stability for CO_(2)RR.Here,we review recent developments in the field of porphyrin-based MOF CO_(2)RR photocatalysts,along with critical issues,challenges,and perspectives concerning porphyrin-based MOF catalysts for photocatalytic CO_(2)RR.展开更多
Exploring the influence of the coordination environment of single-atom catalysts(SACs)on the electrochemical CO_(2)reduction reaction is vital for assessing the reaction mechanism and structure-performance relationshi...Exploring the influence of the coordination environment of single-atom catalysts(SACs)on the electrochemical CO_(2)reduction reaction is vital for assessing the reaction mechanism and structure-performance relationship.However,it is challenging to engineer the coordination configuration of isolated active metal atoms precisely.Herein,we strategically manipulate the coordination number of the Co-N_(x) configuration by simply changing the order of adding the metal precursor toward improved CO_(2)electrolysis performance.Compared with the symmetric Co-N_(4)coordination,the asymmetric Co-N_(3)coordination leads to reinforced Co-N interaction and downshifted 3d orbital energy toward the Fermi level of the active Co sites,promoting the activation of CO_(2)molecules and the formation of critical intermediate^(*)COOH.The as-designed Co-N_(3)SAC displays excellent Faradaic efficiency(FE)of 98.4%for CO_(2)-to-CO conversion at a low potential of-0.80 V,together with decent FE over a wide potential range(-0.50 V to-1.10 V)and high durability.This study presents an ideal platform to manipulate the coordination number of atomically dispersed metal catalysts and provides a fundamental understanding of coordination configurationperformance correlation for CO_(2)electroreduction.展开更多
Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of conta...Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of contaminants,this study develops a two-dimensional axisymmetric model of a linear-type cryocooler to simulate the transport and deposition processes of trace CO_(2),evaluating the impact of contamination on system pressure drop under various operating conditions.Results indicate that CO_(2)diffusion is primarily driven by concentration gradients.The CO_(2)deposition rate increases markedly at low temperatures and high concentrations,with over 90%of deposition occurring in the cold-end heat exchanger.Under different concentration distributions,dry ice predominantly accumulates in the cold-end heat exchanger;however,notable differences emerge in the pulse tube.In the uniform distribution case,CO_(2)tends to deposit along the inner wall of the pulse tube,whereas in the gradual release scenario,deposition mainly occurs on the cold-end flow straightening mesh screen.Dry ice deposition significantly increases the pressure drop across the system and decreases the pressure wave amplitude,resulting in a degradation of cooling capacity.This study lays a foundation for further investigation into the thermal properties of contaminant layers and provides theoretical guidance for optimizing cold-end components to improve contamination resilience.展开更多
MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper...MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.展开更多
Electrocatalytic CO_(2) reduction(CO_(2) RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C_(2+)generation due to th...Electrocatalytic CO_(2) reduction(CO_(2) RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C_(2+)generation due to their unique C–C coupling activity,yet the in situ reduction from Cu^(+) to Cu^(0) under cathodic potentials causes the catalyst deactivation.Herein,we develop a transient thermal shock strategy to embed Cu^(+) species into CeO_(2) lattices,constructing a CuO_(x)/CuCeO_(x)catalyst with a radial gradient Cu^(+) -Ov-Ce^(3+)/Ce^(4+)structure.Depth-profiling X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations reveal that mismatched metal/oxygen diffusion kinetics drive continuous electron transfer from surface Cu^(+) to bulk Ce^(3+)/Ce^(4+)via oxygen vacancies(Ov),forming a dynamic“self-sacrificial”structure to preserve surface Cu^(+) states.In CO_(2)-saturated 0.1 M KHCO_(3),the optimized CuO_(x)/CuCeO_(x)-10 achieves a high C_(2) Faradaic efficiency(FE)of 85.8%at-1.4 V vs.RHE.In situ attenuated total reflection surface-enhanced infrared adsorption spectroscopy(ATR-SEIRAS)identifies the key intermediates of C_(2) are*OCCO and*OCCOH,while DFT reveals a drastic reduction of C–C coupling barrier from 0.842 to0.274 eV.This work demonstrates kinetically tailored metal-support interactions,enabling oxidationstate control for pathway-selective catalysis.展开更多
As the core of cathode materials,sensitive metals play important roles in the optimization of acetate production from carbon dioxide(CO_(2))in microbial electrochemical system(MES).In this work,iron(Fe),copper(Cu),and...As the core of cathode materials,sensitive metals play important roles in the optimization of acetate production from carbon dioxide(CO_(2))in microbial electrochemical system(MES).In this work,iron(Fe),copper(Cu),and nickel(Ni)as sensitive metal cathode materials were evaluated for CO_(2) conversion in MES.The MES with Feelectrode as a promising electrode material demonstrated a superior CO_(2) reduction performance with a maximum acetate accumulation of 417.9±39.2 mg/L,which was 1.5 and 1.7 folds higher than that in the Ni-electrode and Cu-electrode groups,respectively.Furthermore,an outstanding electron recovery efficiency of 67.7%was shown in the Fe-electrode group.The electron transfer between electrode-suspended sludge was systematically cross-evaluated by the electrochemical behavior and extracellular polymeric substances.The Fe-electrode group had the highest electron transfer rate with 0.194 s-1(k_(app)),which was 17.6 and 21.5 times higher than that of the Cu-and Ni-electrode groups,respectively.Fe-electrode was beneficial for reducing electrochemical impedance between the electrode and suspended sludge.Additionally,redox substances in extracellular polymeric substances of the Fe-electrode group were increased,implying more favorable electron transport dynamics.Simultaneously,enrichments of functional bacteria Acetoanerobium and increased key enzymes involved in the carbonyl pathway of the Fe-electrode group were observed,which also promoted CO_(2) conversion in MES.This study provides a perspective on evaluating the promising sensitive metal electrode material for the process of CO_(2) valorization in MES and offers a reference for the subsequent electrode modification.展开更多
In this study,electrochemical C-H carboxylation of benzylamines with CO_(2) was reported.This linear paired electrolysis system enables efficient and economical synthesis of value-added α-amino acids(α-AAs) under mi...In this study,electrochemical C-H carboxylation of benzylamines with CO_(2) was reported.This linear paired electrolysis system enables efficient and economical synthesis of value-added α-amino acids(α-AAs) under mild conditions.Various substituted benzylamines containing diverse functional groups and even highly reactive moieties,such as cyano,amide and alkene groups could be successfully transformed to the carboxylated products.Notably,this method proved to be applicable to the late-stage modification of biorelevant compounds,highlighting its potential for synthetic chemistry.Mechanistic studies such as radical trapping experiments,kinetic isotope effect(KIE) tests and cyclic voltammetry(CV) studies provided useful insight into this transformation.展开更多
文摘The reaction between 3-substituted-4-hydroxy-2H-1.2-be 1.1-dioxides and phenyl isocyanate in the presence of different equivalents of strong base NaH has been studied. The structures of new derivatives were characterized by 1H NMR. IR. elementary analysis and FeCl3 test.
文摘In order to promote our understanding on electronic structure of actinide dioxides, we construct a tight-binding model composed of actinide 5f and oxygen 2p electrons, which is called f-p model. After the diagonalization of the f-p model, we compare the eigen-energies in the first Brillouin zone with the results of relativistic band-structure calculations. Here we emphasize a key role of f-p hybridization in order to understand the electronic structure of actinide dioxides. In particular, it is found that the position of energy levels of Г7 and Г8 states determined from crystalline electric field (CEF) potentials depends on the f-p hybridization. We investiagte the values of the Slater-Koster integrals for f-p hybridization, (fpσ) and (fpπ), which reproduce simultaneously the local CEF states and the band-structure calculation results. Then, we find that the absolute value of (fpπ) should be small in comparison with (fpσ) = 1 eV. The small value of |(fpπ)| is consistent with the condition to obtain the octupole ordering in the previous analysis of the f-p model.
文摘A type of high visible-light active titanium oxinitride(TiO2-xNx)powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures.The hydrated titanium dioxide was synthesized as the precursor of TiO2-xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white.The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied.The visible-light activity and photocatalysis capability of the powder were also investigated.
基金the National Nature Science Foundation of China，the 'Top Hundred Talents' Program of Chinese Academy of Sciences and the National Key Basic Research and Development (973) Program of China (2013CB632300) for financial support
文摘Lamellar compounds such as the disulfides of molybdenum and tungsten are widely used as additives in lubricant oils or as solid lubricants in aerospace industries.The dioxides of these two transition metals have identical microstructures with those of the disulfides.The differences in the lubrication behaviors of disulfide and dioxides were investigated theoretically.Tungsten dioxide and molybdenum dioxide exhibit higher bond strengths at the interface and lower interlayer interactions than those of the disulfides which indicates their superlubricity.Furthermore,the topography of the electron density of the single layer nanostructure determined their sliding potential barrier;the dioxides showed a weaker electronic cloud distribution between the two neighboring oxygen atoms,which facilitated the oxygen atoms of the counterpart to go through.For commensurate friction,the dioxides exhibited nearly the same value of friction work,and same was the case for the disulfides.The lower positive value of friction work for the dioxides confirmed their improved lubricity than the disulfides and the higher mechanical strength of the bulk dioxides demonstrated that they are excellent solid lubricants in vacuum.
基金Supported by National Key R&D Program of China(2022YFA1503400)。
文摘Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol.
基金Supported by Innovation Capability Support Program of Shaanxi(2024RS-CXTD-53,2024ZC-KJXX-096)the Key R&D Program of Shaanxi Province(2022QCY-LL-69)Xi’an Science and Technology Project(24GXFW0089)。
文摘Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting two greenhouse gases(methane and carbon dioxide)into syngas and its promising industrial applications.Nickel(Ni)-based catalysts,with high catalytic activity,low cost,and abundant resources,are considered ideal candidates for industrial applications.In this article,three reaction kinetic models were briefly introduced,namely the Power-Law(PL)model,the Eley-Rideal(ER)model,and the Langmuir-Hinshelwood-Hougen-Watson(LHHW)model.Based on the LHHW model,the reaction kinetics and mechanisms of different catalytic systems were systematically discussed,including the properties of supports,the doping of noble metals and transition metals,the role of promoters,and the influence of the geometric and electronic structures of Ni on the reaction mechanism.Furthermore,the kinetics of carbon deposition and elimination on various catalysts were analyzed.Based on the reaction rate expressions for carbon elimination,the reasons for the high activity of transition metal iron(Fe)-doped catalysts and core-shell structured catalysts in carbon elimination were explained.Based on the detailed collation and comparative analysis of the reaction mechanisms and kinetic characteristics across diverse Ni-based catalytic systems,a theoretical guidance for the designing of high-performance catalysts was provided in this work.
基金Project supported by the National Natural Science Foundation of China.
文摘The reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanate under different equivalents of strong base NaH was studied. Seventeen of new derivatives were obtained whose structures were characterized by H-1 NMR, IR, MS, elementary analysis and FeCl3 test.
基金support provided by the Natural Science Foundation of Jilin Province(YDZJ202401316ZYTS)the Innovation Laboratory Development Program of the Education Department of Jilin Province and the Industry and Information Technology Department of Jilin Province,China(The Joint Laboratory of MXene Materials)the MXene Research Support Plan of Jilin 11 Technology Co.,Ltd.,China,and Future(Jilin)Material Technology Co.,Ltd.
文摘As the carrier of charge storage,the electrode determines the efficiency of the energy conversion reaction between the battery and the substance.However,with the continuous development of scientific research,electrode preparation is still facing complex technical problems,and it is difficult to achieve a balance in performance,cost,and technology.Based on the ion dissolution and deposition behavior of Mn^(2+)/MnO_(2) and Al^(3+)/Al,a novel cathode-free aqueous ion dissolution/deposition battery is designed,which can contribute 15 mAh at 16 cm^(2) in a voltage window of 0.5-1.8 V.The charge storage and the attenuation mechanism are systematically investigated.The battery model with compensable electrolyte was constructed,and the cycle characteristics of the cathode-free aqueous ion dissolution/deposition battery were optimized,which could achieve 1000 h continuous operation.This system provides a low-cost and high-safety solution for future high-energy density and large-scale energy storage.Future research will focus on optimizing electrolytes,controlling deposition morphology,and improving interface stability to further promote the commercialization of cathode-free batteries.
基金supported by the Inoue Enryo Memorial Grant of Toyo University(2023No.63)the He’nan Provincial Natural Science Foundation,China(No.252300420433)the Leading goose research and development plan of Zhejiang,China(No.2023C02039).
文摘To enhance the visible light response of titanium dioxide(TiO_(2)),titanium carbide(TiC)nanoparticles(NPs)were thermally treated in carbon powder,effectively overcoming the challenges associated with conventional doping methods.During the treatment,a TiO_(2)thin shell with oxygen vacancies(OVs)formed around the TiC NPs,creating a shell-core structure S-scheme photocatalyst.Transmission electron microscopy(TEM)and ultraviolet-visible(UV-vis)spectroscopy confirmed the successful formation of the TiO_(2)shell.By optimizing the shell thickness,the TiO_(2)-TiC shell-core structure achieved an ideal shell-core ratio,resulting in strong visible light absorption(400-800 nm),and the degradation rate constant of Rhodamine B(RhB)of sample cHT500 reached 0.0687 min^(−1),which is 20.8times higher than that of pristine TiO_(2)(0.0033 min^(−1))under visible-light irradiation.In addition,cytocompatibility tests showed that sample cHT500 exhibits favorable cell viability,which is comparable to that of TiO_(2)nanoparticles,and thus remarkably mitigates the poor biocompatibility inherent to TiC,making them promising candidates for biomedical and photocatalytic applications.
文摘Efficiency of C-C bond coupling in highly inert CO_(2)is relatively low,which severely limits its efficient conversion to acetate.Here,we successfully developed a highly stable NF@CoMn_(2)O_(4)@Cu_(2)O-Ag bimetallic active site catalyst by anchoring Ag on the Cu_(2)O surface.In this catalyst,the Co^(3+)/Mn^(3+)-Mn^(4+)removes excess electrons from the Cu+sites via strong electronic interactions,preventing the reduction of Cu_(2)O to metallic Cu^(0),which ensures the NF@CoMn_(2)O_(4)@Cu_(2)O-Ag exhibits a high resistance to deactivation.The Cu+active sites of NF@CoMn_(2)O_(4)@Cu_(2)O-Ag efficiently electroreduce CO_(2)to the*COatop intermediate,while the Ag active sites efficiently electroreduce CO_(2)to the^(*)CO_(bridge)intermediate.The proximity of Cu+/Ag bimetallic sites shortens the distance for C-C bond coupling between the*COatop and^(*)CO_(bridge)intermediates,facilitating the efficient electrocatalytic coupling of CO_(2)to synthesize acetate.DFT analysis indicates that theΔG required for C-C bond coupling on the short-distance Cu+/Ag bimetallic sites of NF@CoMn_(2)O_(4)@Cu_(2)O-Ag is significantly lower than that of NF@CoMn_(2)O_(4)@Cu_(2)O,enabling a high Faradaic efficiency of 64.97%for acetate production at-0.3 V vs.RHE.This study provides an effective strategy for the rational design of synergistic catalysis between heterometallic catalytic sites to efficiently achieve C-C coupling for the synthesis of C2+products.
基金supported by the National Key R&D Program of China(No.2023YFC3710800)the National Natural Science Foundation of China(No.22376207)+1 种基金the Research Fund of High-Level Training Talents of“333”Project in Jiangsu provinceFunding for school-level research projects of Yancheng Institute of Technology(Nos.xjr2024008 and xjr2023055).
文摘Artificial synthesis is an environment friendly photocatalytic strategy to converse carbon dioxide(CO_(2))into useful chemicals.However,water(H_(2)O)splitting,producing(hydrogen)H_(2) strongly,is always a competitive reaction to CO_(2) conversion.Therefore,proper cocatalysts are generally needed to enhance CO_(2) conversion but suppress H_(2) production.In this work,zinc/gallium(Zn/Ga)dual co-catalysts consisting of Zn0 and amorphous ZnGa_(2)O_(4) species were found to selectively produce carbon monoxide(CO)during the photocatalytic conversion of carbon dioxide(CO_(2))using water(H_(2)O)as an electron donor over photocatalysts such as NaTaO_(3),Ga_(2)O_(3),and ZnGa_(2)O_(4),and in the electrochemical reduction of CO_(2) over Zn0 electrodes.It is considered that there are two effects associated with the Zn/Ga dual co-catalysts:(1)a galvanic cell effect between Zn0 and amorphous ZnGa_(2)O_(4),and(2)a Z-scheme effect in NaTaO_(3)/Zn0/amorphous ZnGa_(2)O_(4).The coupling of these two effects favored the active and selective evolution of CO during the photocatalytic conversion of CO_(2) by H_(2)O.In the case of Ga_(2)O_(3) photocatalyst,480.8μmol/h of CO was produced with the presence of Zn/Ga dual cocatalysts.Moreover,the Zn/Ga dual cocatalysts universally worked in the electrochemical reduction of CO_(2).The partial current toward CO_(2) conversion was increased from 2.6 to 6.6 mA/cm,and the selectivity toward CO was promoted to from 46.4%to 74.2%.
基金supports of the National Natural Science Foundation of China(NSFC)(52021004,52394202)key project of the Joint Fund for Innovation and Development of Chongqing Natural Science Foundation(CSTB2022NSCQ-LZX0013)+1 种基金the National Natural Science Foundation of China(NSFC)(52301232,and 52476056)the Natural Science Foundation of Chongqing Province(2024NSCQ-MSX1109).
文摘Controllable synthesis of ultrathin metallene nanosheets and rational design of their spatial arrangement in favor of electrochemical catalysis are critical for their renewable energy applications.Here,a biomimetic design of“Trunk-Branch-Leaf”strategy is proposed to prepare the ultrathin edge-riched Zn-ene“leaves”with a thickness of~2.5 nm,adjacent Zn-ene cross-linked with each other,which are supported by copper nanoneedle“branches”on copper mesh“trunks,”named as Zn-ene/Cu-CM.The resulting superstructure enables the formation of an interconnected network and multiple channels,which can be used as an electrocatalytic CO_(2) reduction reaction(CO_(2)RR)electrode to allow a fast charge and mass transfer as well as a large electrolyte reservoir.By virtue of the distinctive structure,the obtained Zn-ene/Cu-CM electrode exhibits excellent selectivity and activity toward CO production with a maximum Faradaic efficiency of 91.3%and incredible partial current density up to 40 mA cm^(−2),outperforming most of the state-of-the-art Zn-based electrodes for CO_(2) reduction.The phenolphthalein color probe combined with in situ attenuated total reflection-infrared spectroscopy uncovered the formation of the localized pseudo-alkaline microenvironment at the interface of the Zn-ene/Cu-CM electrode.Theoretical calculations confirmed that the localized pH as the origin is responsible for the adsorption of CO_(2) at the interface and the generation of *COOH and *CO intermediates.This study offers valuable insights into developing efficient electrodes through synergistic regulation of reaction microenvironments and active sites,thereby facilitating the electrolysis of practical CO_(2) conversion.
基金financially supported by the National Natural Science Foundation of China(No.22305009)the Science and Technology Development Fund,Macao SAR(File no.FDCT-0125/2022/A and FDCT-0006/2023/RIB1)Hong Kong Research Grant Council(RGC)General Research Fund(GRF)City U 11305419,11306920,CityU 11308721,CityU 11316522,and SIRG7020022。
文摘Photocatalytic carbon dioxide reduction reaction(CO_(2)RR)is a carbon-neutral strategy to address global energy use and its impact on climate.Metal oxide and metal chalcogenide catalysts are the most investigated catalysts for photocatalytic CO_(2)RR.Unfortunately,low CO_(2)adsorption ability and limited active sites of metal oxide and metal chalcogenide catalysts for CO_(2)RR make them less competitive compared to their industrial counterparts.Inspired by applications of porphyrin-based metal-organic framework(MOF)catalysts for hydrogen evolution and photodynamic therapy,the investigations of these porphyrin-based MOFs,including pristine and composite porphyrin-based MOFs in photocatalytic CO_(2)RR,have attracted significant attention in the last five years due to their excellent CO_(2)adsorption capacities,high porosity,high stability,exceptional optoelectronic properties,and multi-functionality.However,due to the difference in photocatalytic CO_(2)RR,several critical issues need to be addressed to achieve the rational design of advanced porphyrin-based MOF photocatalysts to improve activity,selectivity,and stability for CO_(2)RR.Here,we review recent developments in the field of porphyrin-based MOF CO_(2)RR photocatalysts,along with critical issues,challenges,and perspectives concerning porphyrin-based MOF catalysts for photocatalytic CO_(2)RR.
基金financially supported by the Program for the Development of Science and Technology of Jilin Province(No.20240101004JJ)the National Natural Science Foundation of China(No.22409165)+4 种基金the National Foreign Experts Program of the Ministry of Human Resources and Social Security(No.Y20240003)the Shaanxi Province Talent Programfinancially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDB0600000,XDB0600100,XDB0600200,XDB0600300,XDB0600400)Liaoning Binhai Laboratory(No.LILBLB-2023-04)Dalian Revitalization Talents Program(No.2022RG01)。
文摘Exploring the influence of the coordination environment of single-atom catalysts(SACs)on the electrochemical CO_(2)reduction reaction is vital for assessing the reaction mechanism and structure-performance relationship.However,it is challenging to engineer the coordination configuration of isolated active metal atoms precisely.Herein,we strategically manipulate the coordination number of the Co-N_(x) configuration by simply changing the order of adding the metal precursor toward improved CO_(2)electrolysis performance.Compared with the symmetric Co-N_(4)coordination,the asymmetric Co-N_(3)coordination leads to reinforced Co-N interaction and downshifted 3d orbital energy toward the Fermi level of the active Co sites,promoting the activation of CO_(2)molecules and the formation of critical intermediate^(*)COOH.The as-designed Co-N_(3)SAC displays excellent Faradaic efficiency(FE)of 98.4%for CO_(2)-to-CO conversion at a low potential of-0.80 V,together with decent FE over a wide potential range(-0.50 V to-1.10 V)and high durability.This study presents an ideal platform to manipulate the coordination number of atomically dispersed metal catalysts and provides a fundamental understanding of coordination configurationperformance correlation for CO_(2)electroreduction.
基金supported by the National Natural Science Foundation of China(No.52376012)the Aeronautical Science Foundation of China(20230024047001).
文摘Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of contaminants,this study develops a two-dimensional axisymmetric model of a linear-type cryocooler to simulate the transport and deposition processes of trace CO_(2),evaluating the impact of contamination on system pressure drop under various operating conditions.Results indicate that CO_(2)diffusion is primarily driven by concentration gradients.The CO_(2)deposition rate increases markedly at low temperatures and high concentrations,with over 90%of deposition occurring in the cold-end heat exchanger.Under different concentration distributions,dry ice predominantly accumulates in the cold-end heat exchanger;however,notable differences emerge in the pulse tube.In the uniform distribution case,CO_(2)tends to deposit along the inner wall of the pulse tube,whereas in the gradual release scenario,deposition mainly occurs on the cold-end flow straightening mesh screen.Dry ice deposition significantly increases the pressure drop across the system and decreases the pressure wave amplitude,resulting in a degradation of cooling capacity.This study lays a foundation for further investigation into the thermal properties of contaminant layers and provides theoretical guidance for optimizing cold-end components to improve contamination resilience.
基金support from the Key projects of scientific research projects of universities in Anhui Province(2024AH050360).
文摘MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.
基金financially supported by the National Natural Science Foundation of China(22378428,22138013)the National Key Research and Development Program of China(2023YFB4104500,2023YFB4104503)+1 种基金the Key Research and Development Program of Shandong Province(2024ZLGX08)the Science and Technology Innovation Project of the Shandong Energy Group Co.,Ltd.(SNKJ2023A03)。
文摘Electrocatalytic CO_(2) reduction(CO_(2) RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C_(2+)generation due to their unique C–C coupling activity,yet the in situ reduction from Cu^(+) to Cu^(0) under cathodic potentials causes the catalyst deactivation.Herein,we develop a transient thermal shock strategy to embed Cu^(+) species into CeO_(2) lattices,constructing a CuO_(x)/CuCeO_(x)catalyst with a radial gradient Cu^(+) -Ov-Ce^(3+)/Ce^(4+)structure.Depth-profiling X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations reveal that mismatched metal/oxygen diffusion kinetics drive continuous electron transfer from surface Cu^(+) to bulk Ce^(3+)/Ce^(4+)via oxygen vacancies(Ov),forming a dynamic“self-sacrificial”structure to preserve surface Cu^(+) states.In CO_(2)-saturated 0.1 M KHCO_(3),the optimized CuO_(x)/CuCeO_(x)-10 achieves a high C_(2) Faradaic efficiency(FE)of 85.8%at-1.4 V vs.RHE.In situ attenuated total reflection surface-enhanced infrared adsorption spectroscopy(ATR-SEIRAS)identifies the key intermediates of C_(2) are*OCCO and*OCCOH,while DFT reveals a drastic reduction of C–C coupling barrier from 0.842 to0.274 eV.This work demonstrates kinetically tailored metal-support interactions,enabling oxidationstate control for pathway-selective catalysis.
基金supported by the Science and Technology Commission of Shanghai Municipality Foundation(No.22230710500)the Interdisciplinary joint research project of Tongji University(No.2023-3-YB-07).
文摘As the core of cathode materials,sensitive metals play important roles in the optimization of acetate production from carbon dioxide(CO_(2))in microbial electrochemical system(MES).In this work,iron(Fe),copper(Cu),and nickel(Ni)as sensitive metal cathode materials were evaluated for CO_(2) conversion in MES.The MES with Feelectrode as a promising electrode material demonstrated a superior CO_(2) reduction performance with a maximum acetate accumulation of 417.9±39.2 mg/L,which was 1.5 and 1.7 folds higher than that in the Ni-electrode and Cu-electrode groups,respectively.Furthermore,an outstanding electron recovery efficiency of 67.7%was shown in the Fe-electrode group.The electron transfer between electrode-suspended sludge was systematically cross-evaluated by the electrochemical behavior and extracellular polymeric substances.The Fe-electrode group had the highest electron transfer rate with 0.194 s-1(k_(app)),which was 17.6 and 21.5 times higher than that of the Cu-and Ni-electrode groups,respectively.Fe-electrode was beneficial for reducing electrochemical impedance between the electrode and suspended sludge.Additionally,redox substances in extracellular polymeric substances of the Fe-electrode group were increased,implying more favorable electron transport dynamics.Simultaneously,enrichments of functional bacteria Acetoanerobium and increased key enzymes involved in the carbonyl pathway of the Fe-electrode group were observed,which also promoted CO_(2) conversion in MES.This study provides a perspective on evaluating the promising sensitive metal electrode material for the process of CO_(2) valorization in MES and offers a reference for the subsequent electrode modification.
基金Financial support from National Key R&D Program of China (No.2023YFA1507203)National Natural Science Foundation of China (Nos.22371149 and 22188101)+3 种基金the Fundamental Research Funds for the Central Universities (No.63224098)Frontiers Science Center for New Organic Matter,Nankai University (No.63181206)Nankai University are gratefully acknowledgedthe Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘In this study,electrochemical C-H carboxylation of benzylamines with CO_(2) was reported.This linear paired electrolysis system enables efficient and economical synthesis of value-added α-amino acids(α-AAs) under mild conditions.Various substituted benzylamines containing diverse functional groups and even highly reactive moieties,such as cyano,amide and alkene groups could be successfully transformed to the carboxylated products.Notably,this method proved to be applicable to the late-stage modification of biorelevant compounds,highlighting its potential for synthetic chemistry.Mechanistic studies such as radical trapping experiments,kinetic isotope effect(KIE) tests and cyclic voltammetry(CV) studies provided useful insight into this transformation.
