Elemental doping of BiVO_(4) crystal lattices effectively enhances carrier separation,thereby facilitating efficient photoelectrochemical water splitting.However,the positive effect of elementally induced lattice dist...Elemental doping of BiVO_(4) crystal lattices effectively enhances carrier separation,thereby facilitating efficient photoelectrochemical water splitting.However,the positive effect of elementally induced lattice distortions on hole extraction has been neglected.Herein,the crystal lattice of BiVO_(4) is distorted by doping with an inexpensive Cs metal;then,CoFe_(2)O_(4) is used as an efficient hole-extraction layer to further modify the surface of the doped photoanode.Benefiting from the above design,the newly prepared CoFe_(2)O_(4)-Cs-BiVO_(4) photoanode achieved a photocurrent density of 5.66 mA cm^(–2) at 1.23 V vs.a reversible hydrogen electrode,indicating a 3.9-fold improvement in photocurrent density.Detailed physicochemical characterization and density functional theory calculations showed that the lattice distortion induced by Cs doping promoted the directional migration of BiVO_(4) bulk-phase holes to the CoFe_(2)O_(4) layer.Additionally,the coupled CoFe_(2)O_(4) can be used as a hole extraction layer to further enhance the interfacial migration of carriers.The synergistic effect of the two effectively promotes the directional migration of photogenerated carriers from the BiVO_(4) bulk phase to the active sites of the oxygen evolution reaction,thereby effectively inhibiting carrier recombination.This study revealed the positive effect of the dual-hole extraction strategy on solar energy conversion,thereby opening new avenues for the rational design of photoanodes.展开更多
Constructing vacancy-decorated metal halide perovskites(MHPs)have emerged as promising pathway to enhance photocatalytic activity and selectivity for solar CO_(2)reduction.However,the controllable construction of vaca...Constructing vacancy-decorated metal halide perovskites(MHPs)have emerged as promising pathway to enhance photocatalytic activity and selectivity for solar CO_(2)reduction.However,the controllable construction of vacancy defects is still challenging,and our understanding of the roles of these defects,particularly their effects on the adsorption activation of surface reaction molecules,is still insufficient.Herein,we elaborately designed and synthesized adjustable Br vacancies in CsPbBr_(3)catalysts by manipulating the dissolution and recrystallization speed of precursors during the ball milling process using solvents with gradient polarities.We found that the Br vacancies could promote the charge separation,while having slight influence on the band structure of CsPbBr_(3).More importantly,temperature-programmed desorption results combined with theoretical calculations revealed that Br vacancies can significantly enhance the adsorption of CO_(2)and CO on the surface,specifically increasing the adsorption strength between CO and the active sites.This finding provides a substantial opportunity for achieving high activity and selectivity in photocatalytic CO_(2)methanation.Accordingly,a high rate of CO_(2)photoreduction to CH_(4)up to 17.94±0.81μmol g^(-1)h^(-1)along with superior selectivity of 95.8%were acquired for CsPbBr_(3)-HX featuring with the richest Br vacancy defects,which is 18.9-fold compared that of CsPbBr_(3)-CAN with the lowest Br vacancy defects.This investigation deepens insights into action mechanism of defects on halide perovskites catalysts,offering a novel strategy for the high-effective conversion of CO_(2)into valuable products.展开更多
Building heterojunctions has proven its efficiency in promoting charge separation for highly efficient photocatalysis.However,most heterojunctions often suffer from inadequate interfacial contact between the two semic...Building heterojunctions has proven its efficiency in promoting charge separation for highly efficient photocatalysis.However,most heterojunctions often suffer from inadequate interfacial contact between the two semiconductor phases,hindering charge separation and producing suboptimal photocatalytic performance.Herein,leveraging the soft lattice feature of halide perovskite,we intentionally introduced In_(2)O_(3)nanoparticles as seeds in situ during the crystallization process of CsPbBr_(3),constructing In_(2)O_(3)/CsPbBr_(3)heterojunction with intimate and abundant interface contact.Through in situ X-ray photoelectron spectroscopy and band structure analysis,we revealed the creation of a direct Z-type heterojunction that combines the catalytic advantages of both CsPbBr_(3)and In_(2)O_(3)for CO_(2)reduction and water oxidation,respectively.The enhanced interfacial contact further enables this heterojunction to separate more photogenerated charges and prolong carrier lifetime effectively.Benefiting from the improved charge utilization,as well as the chemisorption and activation of CO_(2)molecules on the catalyst,the In_(2)O_(3)/CsPbBr_(3)heterojunction exhibits significantly enhanced performance in CO_(2)photoreduction,achieving a 3.8-fold increase in the photoelectron consumption rate as compared to that of CsPbBr_(3)alone.This study emphasizes the critical importance of a tight and rich heterojunction interface in achieving efficient photocatalytic reactions.展开更多
The neutral hydrogen evolution reaction(HER)is vital in the chemical industry,and its efficiency depends on the interior character of the catalyst.Herein,work function(WF)engineering is introduced via 3d metal(Fe,Co,N...The neutral hydrogen evolution reaction(HER)is vital in the chemical industry,and its efficiency depends on the interior character of the catalyst.Herein,work function(WF)engineering is introduced via 3d metal(Fe,Co,Ni,and Cu)doping for modulating the Fermi energy level of Mo2C.The defective energy level facilitates the free water molecule adsorption and,subsequently,promotes the neutral HER efficiency.Specifically,at a current density of 10 mA/cm2,Cu-Mo2C exhibits the best HER performance with an overpotential of 78 mV,followed by Ni-Mo2C,Co-Mo2C,Fe-Mo2C,and bare Mo2C with 90,95,100,and 173 mV,respectively,and the corresponding Tafel slope values are 40,43,42,56,and 102 mV/dec.The modified WF can also lead to an enhanced photocatalytic efficiency owing to the lowered Schottky barrier and excellent carrier transition across the electrocatalyst–solution interface.When coupling the metal-doped Mo2C samples with TiO2,enhanced photocatalytic neutral HER rates are obtained in comparison to the case with bare TiO2.Typically,the HER rates are 521,404,275,224,147,and 112μmol/h for Cu,Ni,Co,Fe,bare Mo2C,and bare TiO2,respectively.Time-resolved photoluminescence spectroscopy(TRPS)and ultrafast transient absorption(TA)measurements are carried out to confirm the recombination and migration of the photogenerated carriers.The fittedτvalues from the TRPS curves are 22.6,20.5,10.1,4.7,4.0,2.5,and 1.9 ns for TiO2,TiO2-Mo2C,TiO2-Fe-Mo2C,TiO2-Fe-Mo2C,TiO2-Fe-Mo2C,TiO2-Fe-Mo2C,and TiO2-Pt,respectively.Additionally,the fittedτvalues from the TA results are 31,73,and 105 ps for the TiO2-Mo2C,TiO2-Cu-Mo2C,and TiO2-Pt samples,respectively.This work provides in-depth insights into the WF modulation of an electrocatalyst for improving the HER performance.展开更多
Hydrogen evolution from water electrolysis has become an important reaction for the green energy revolution.Traditional precious metals and their compounds are excellent catalysts for producing hydrogen;however,their ...Hydrogen evolution from water electrolysis has become an important reaction for the green energy revolution.Traditional precious metals and their compounds are excellent catalysts for producing hydrogen;however,their high cost limits their large-scale practical application.Therefore,the development of affordable electrocatalysts to replace these precious metals is important.Transition metal phosphides(TMPs)have shown remarkable performance for hydrogen evolution and garnered considerable interest in the field of electrolysis.Based on the detailed introduction of TMPs in previous studies,we have systematically summarized the preparation methods,improvement methods,and development opportunities of TMPs and proposed“stimulatory factors”as a fundamental factor affecting the performance of TMPs herein.As the core of this research,“stimulatory factors”can provide numerous solutions to improve the performance of TMP materials and provide a good starting point for TMP research.展开更多
Hydrogen generation via artificial photosynthesis paves a promising way to remit the ever-increasing energy crisis and deteriorative environmental issues.Among all the materials utilized for solar hydrogen production,...Hydrogen generation via artificial photosynthesis paves a promising way to remit the ever-increasing energy crisis and deteriorative environmental issues.Among all the materials utilized for solar hydrogen production,perovskite has emerged as a rising star due to its superior optoelectronic properties.This manuscript aims to provide a comprehensive review summarizing the recent inspiring advancements on perovskite-based solar hydrogen production systems,including the particulate photocatalysis,photoelectrochemical cells,and photovoltaic-electrocatalytic cells.We start with a brief introduction of the advantages of perovskites for solar hydrogen production and the basic principles of the three most prominent solar hydrogen production systems.The representative progresses in this field are then detailed with a special emphasis on the strategies to improve the efficiency and the stability of the systems.Finally,challenges and opportunities for the further development of the PVK-based solar hydrogen production systems are presented with perspective given on outlook,performance,cost and stability.展开更多
Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)holds great promise in green energy conversion and storage.However,for current CO_(2) electrolyzers that rely on the oxygen evolution reaction,a large portion of the...Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)holds great promise in green energy conversion and storage.However,for current CO_(2) electrolyzers that rely on the oxygen evolution reaction,a large portion of the input energy is"wasted"at the anode due to the high overpotential requirement and the recovery of low-value oxygen.To make efficient use of the electricity during electrolysis,coupling CO_(2)RR with anodic alternatives that have low energy demands and/or profitable returns with high-value products is then promising.Herein,we review the latest advances in paired systems for simultaneous CO_(2) reduction and anode valorization.We start with the cases integrating CO_(2)RR with concurrent alternative oxidation,such as inorganic oxidation using chloride,sulfide,ammonia and urea,and organic oxidation using alcohols,aldehydes and primary amines.The paired systems that couple CO_(2)RR with on-site oxidative upgrading of CO_(2)-reduced chemicals are also introduced.The coupling mechanism,electrochemical performance and economic viability of these co-electrolysis systems are discussed.Thereby,we then point out the mismatch issues between the cathodic and anodic reactions regrading catalyst ability,electrolyte solution and reactant supply that will challenge the applications of these paired electrolysis systems.Opportunities to address these issues are further proposed,providing some guidance for future research.展开更多
Providing efficient charge transfer through the interface between the semiconductor and co-catalyst is greatly desired in photoelectrocatalytic (PEC) energy conversion.Herein,we excogitate a novel and facile means,via...Providing efficient charge transfer through the interface between the semiconductor and co-catalyst is greatly desired in photoelectrocatalytic (PEC) energy conversion.Herein,we excogitate a novel and facile means,via electrochemical activation,to successfully load the amorphous CoOOH layer architecture onto the surface of TiO_(2).Intriguingly,the as-obtained 6%CoOOH-TiO_(2)photoelectrode manifests optimal PEC performance with a high photocurrent density of 1.3 mA/cm~2,3.5 times higher than that of pristine TiO_(2).Electrochemical impedance spectroscopy (EIS),Tafel analysis and cyclic voltammetry (CV) methods show that the carrier transfer barrier within the electrode and the transition of Co^(3+)OOH to Co^(4+)OOH have the dominating effects on the PEC performance.Theoretical calculation reveals that the interface between the CoOOH and TiO_(2)improves the homogeneity of effective d-orbital electronic-transfer ability among Co sites.This research sheds light on the water oxidation reaction and the design of more favorable PEC cocatalysts.展开更多
Nickel oxides and(oxy)hydroxides are promising replacements for noble-metal-based catalysts owing to their high activity and good long-term stability for the oxygen evolution reaction(OER). Herein, we developed nanopo...Nickel oxides and(oxy)hydroxides are promising replacements for noble-metal-based catalysts owing to their high activity and good long-term stability for the oxygen evolution reaction(OER). Herein, we developed nanoporous Ni by a method of combined rapid solidification and chemical dealloying. Subsequently,nanoporous Ni O was obtained via heating treatment, the macropore and skeleton sizes of the NiO originated from Ni10Al90 alloy are 100–300 nm and 80–200 nm, respectively. Benefiting from the multi-stage nanoporous structure and high specific surface area, the nanoporous NiO demonstrates an outstanding OER, reaching 20 mA cm-2 at an overpotential of 356 mV in 1 M KOH. The corresponding Tafel slope and apparent activation energy are measured to be 76.73 mV dec-1 and 29.0 kJ mol-1, respectively. Moreover,kinetic analysis indicates that the Ni O catalyst shows pseudocapacitive characteristics, and the improved current is attributed to the high-rate pseudocapacitive behavior that efficiently maintains increased nickel redox cycling to accelerate the reaction rates. After 1000 cycles of voltammetry, the overpotential of the NiO decreases by 22 mV(j = 10 mA cm-2), exhibiting excellent stability and durability.展开更多
Background and Aims:Further decompensation in cirrhosis is associated with increased mortality.However,reliable tools to predict further decompensation after transjugular intrahepatic portosystemic shunt(TIPS)are curr...Background and Aims:Further decompensation in cirrhosis is associated with increased mortality.However,reliable tools to predict further decompensation after transjugular intrahepatic portosystemic shunt(TIPS)are currently limited.This study aimed to investigate the incidence and risk factors of further decompensation within one year post-TIPS in patients with cirrhosis and to develop a predictive model for identifying high-risk individuals.Methods:This retrospective cohort study enrolled 152 patients with cirrhosis undergoing TIPS for variceal bleeding and/or refractory ascites(January 2018-January 2024).Patients were stratified according to one-year decompensation outcomes.LASSO regression and multivariable logistic analysis were used to identify predictors,and a nomogram was constructed and internally validated using bootstrapping(1,000 replicates).Results:Among the 152 patients(median age 57.5 years[IQR 50.0-66.0];58.6%male;58.6%viral/alcohol-associated etiology),65.8%(100/152)achieved clinical stability at one year post-TIPS,while 34.2%(52/152)developed further decompensation.LASSO regression identified right hepatic lobe volume,spleen volume,and portal pressure gradient(PPG)reduction as key predictors,all independently associated with further decompensation risk in multivariable analysis(OR[95%CI]:0.683[0.535-0.873],1.435[1.240-1.661],and 0.961[0.927-0.996],respectively).The nomogram demonstrated superior discrimination compared with PPG reduction alone and benchmark prognostic scores(AUC 0.854[0.792-0.915] vs.0.619-0.652;△AUC +0.201-+0.235,p<0.001)with 92.3%sensitivity.High-risk patients(score>86)had a 10.7-fold higher risk of further decompensation than lowrisk patients(60.0%vs.5.6%;p<0.0001).Conclusions:This validated model,combining hepatosplenic volumetry and PPG reduction,accurately stratifies further decompensation risk post-TIPS and may guide targeted surveillance and preventive interventions.展开更多
High nickel content layered cathodes,represented by NCM(LiNi_(x)Co_(y)Mn_(z)O_(2),x+y+z=1),are now widely employed in the market of electric vehicles,owing to their high energy density.With the gradual increase of nic...High nickel content layered cathodes,represented by NCM(LiNi_(x)Co_(y)Mn_(z)O_(2),x+y+z=1),are now widely employed in the market of electric vehicles,owing to their high energy density.With the gradual increase of nickel content and capacity,the issues on cycling life and safety become more serious.In this review,various strategies for improving the performance of high nickel NCM are summarized on the aspects of surface coating,ionic doping,and singlecrystal NCM.The coating strategy was separately described according to the physical property of coating species,including inert material coating,Li^(+)-conductor coating,electronic conductor coating,and mixed conductor coating.These coating species help to suppress the interfacial oxidation of electrolytes by NCM,improving the cycling life and safety.The elemental doping in the crystal lattice of NCM is then presented in the aspects of cation,anion,and mixed-ion doping,which are beneficial to stabilize the layered structure during charge–discharge and so promote the electrochemical performance.In quite recent years,the strategy of single-crystal NCM was demonstrated to be a promising pathway,owing to the dramatically reduced surface area and grain boundary.Finally,the remaining unsolved challenges and future strategies for further development of NCM cathode materials are outlined.展开更多
文摘Elemental doping of BiVO_(4) crystal lattices effectively enhances carrier separation,thereby facilitating efficient photoelectrochemical water splitting.However,the positive effect of elementally induced lattice distortions on hole extraction has been neglected.Herein,the crystal lattice of BiVO_(4) is distorted by doping with an inexpensive Cs metal;then,CoFe_(2)O_(4) is used as an efficient hole-extraction layer to further modify the surface of the doped photoanode.Benefiting from the above design,the newly prepared CoFe_(2)O_(4)-Cs-BiVO_(4) photoanode achieved a photocurrent density of 5.66 mA cm^(–2) at 1.23 V vs.a reversible hydrogen electrode,indicating a 3.9-fold improvement in photocurrent density.Detailed physicochemical characterization and density functional theory calculations showed that the lattice distortion induced by Cs doping promoted the directional migration of BiVO_(4) bulk-phase holes to the CoFe_(2)O_(4) layer.Additionally,the coupled CoFe_(2)O_(4) can be used as a hole extraction layer to further enhance the interfacial migration of carriers.The synergistic effect of the two effectively promotes the directional migration of photogenerated carriers from the BiVO_(4) bulk phase to the active sites of the oxygen evolution reaction,thereby effectively inhibiting carrier recombination.This study revealed the positive effect of the dual-hole extraction strategy on solar energy conversion,thereby opening new avenues for the rational design of photoanodes.
基金financially supported by the National Natural Science Foundation of China(Nos.22072081,22302148)the Nature Science Foundation of Shaanxi in China(No.2024JC-YBQN-0468)+1 种基金Scientific Research Program Funded by Education Department of Shaanxi Provincal Government(Nos.22JK0379,24JK0665)Youth Talent Scientific Research Program Funded by Weinan Normal University(No.2022RC17).
文摘Constructing vacancy-decorated metal halide perovskites(MHPs)have emerged as promising pathway to enhance photocatalytic activity and selectivity for solar CO_(2)reduction.However,the controllable construction of vacancy defects is still challenging,and our understanding of the roles of these defects,particularly their effects on the adsorption activation of surface reaction molecules,is still insufficient.Herein,we elaborately designed and synthesized adjustable Br vacancies in CsPbBr_(3)catalysts by manipulating the dissolution and recrystallization speed of precursors during the ball milling process using solvents with gradient polarities.We found that the Br vacancies could promote the charge separation,while having slight influence on the band structure of CsPbBr_(3).More importantly,temperature-programmed desorption results combined with theoretical calculations revealed that Br vacancies can significantly enhance the adsorption of CO_(2)and CO on the surface,specifically increasing the adsorption strength between CO and the active sites.This finding provides a substantial opportunity for achieving high activity and selectivity in photocatalytic CO_(2)methanation.Accordingly,a high rate of CO_(2)photoreduction to CH_(4)up to 17.94±0.81μmol g^(-1)h^(-1)along with superior selectivity of 95.8%were acquired for CsPbBr_(3)-HX featuring with the richest Br vacancy defects,which is 18.9-fold compared that of CsPbBr_(3)-CAN with the lowest Br vacancy defects.This investigation deepens insights into action mechanism of defects on halide perovskites catalysts,offering a novel strategy for the high-effective conversion of CO_(2)into valuable products.
基金financially supported by the National Natural Science Foundation of China(Nos.22302148,22261160369)Natural Science Foundation of Shaanxi Province(No.2024JCYBQN-0468)+3 种基金Science and Technology Program of Shaanxi Province(No.2024ZC-KJXX-059)Key Research and Development Project of Weinan City(No.2024ZDYFJH-636)Scientific Research Program Funded by Education Department of Shaanxi Provincial Government(No.22JK0379)Fundamental Research Funds for the Central Universities(No.GK202406030)。
文摘Building heterojunctions has proven its efficiency in promoting charge separation for highly efficient photocatalysis.However,most heterojunctions often suffer from inadequate interfacial contact between the two semiconductor phases,hindering charge separation and producing suboptimal photocatalytic performance.Herein,leveraging the soft lattice feature of halide perovskite,we intentionally introduced In_(2)O_(3)nanoparticles as seeds in situ during the crystallization process of CsPbBr_(3),constructing In_(2)O_(3)/CsPbBr_(3)heterojunction with intimate and abundant interface contact.Through in situ X-ray photoelectron spectroscopy and band structure analysis,we revealed the creation of a direct Z-type heterojunction that combines the catalytic advantages of both CsPbBr_(3)and In_(2)O_(3)for CO_(2)reduction and water oxidation,respectively.The enhanced interfacial contact further enables this heterojunction to separate more photogenerated charges and prolong carrier lifetime effectively.Benefiting from the improved charge utilization,as well as the chemisorption and activation of CO_(2)molecules on the catalyst,the In_(2)O_(3)/CsPbBr_(3)heterojunction exhibits significantly enhanced performance in CO_(2)photoreduction,achieving a 3.8-fold increase in the photoelectron consumption rate as compared to that of CsPbBr_(3)alone.This study emphasizes the critical importance of a tight and rich heterojunction interface in achieving efficient photocatalytic reactions.
文摘The neutral hydrogen evolution reaction(HER)is vital in the chemical industry,and its efficiency depends on the interior character of the catalyst.Herein,work function(WF)engineering is introduced via 3d metal(Fe,Co,Ni,and Cu)doping for modulating the Fermi energy level of Mo2C.The defective energy level facilitates the free water molecule adsorption and,subsequently,promotes the neutral HER efficiency.Specifically,at a current density of 10 mA/cm2,Cu-Mo2C exhibits the best HER performance with an overpotential of 78 mV,followed by Ni-Mo2C,Co-Mo2C,Fe-Mo2C,and bare Mo2C with 90,95,100,and 173 mV,respectively,and the corresponding Tafel slope values are 40,43,42,56,and 102 mV/dec.The modified WF can also lead to an enhanced photocatalytic efficiency owing to the lowered Schottky barrier and excellent carrier transition across the electrocatalyst–solution interface.When coupling the metal-doped Mo2C samples with TiO2,enhanced photocatalytic neutral HER rates are obtained in comparison to the case with bare TiO2.Typically,the HER rates are 521,404,275,224,147,and 112μmol/h for Cu,Ni,Co,Fe,bare Mo2C,and bare TiO2,respectively.Time-resolved photoluminescence spectroscopy(TRPS)and ultrafast transient absorption(TA)measurements are carried out to confirm the recombination and migration of the photogenerated carriers.The fittedτvalues from the TRPS curves are 22.6,20.5,10.1,4.7,4.0,2.5,and 1.9 ns for TiO2,TiO2-Mo2C,TiO2-Fe-Mo2C,TiO2-Fe-Mo2C,TiO2-Fe-Mo2C,TiO2-Fe-Mo2C,and TiO2-Pt,respectively.Additionally,the fittedτvalues from the TA results are 31,73,and 105 ps for the TiO2-Mo2C,TiO2-Cu-Mo2C,and TiO2-Pt samples,respectively.This work provides in-depth insights into the WF modulation of an electrocatalyst for improving the HER performance.
基金the National Natural Science Foundation of China(Nos.22072081,22002084)the Fundamental Research Funds for the Central Universities(Nos.GK202201003,GK2021103111)。
文摘Hydrogen evolution from water electrolysis has become an important reaction for the green energy revolution.Traditional precious metals and their compounds are excellent catalysts for producing hydrogen;however,their high cost limits their large-scale practical application.Therefore,the development of affordable electrocatalysts to replace these precious metals is important.Transition metal phosphides(TMPs)have shown remarkable performance for hydrogen evolution and garnered considerable interest in the field of electrolysis.Based on the detailed introduction of TMPs in previous studies,we have systematically summarized the preparation methods,improvement methods,and development opportunities of TMPs and proposed“stimulatory factors”as a fundamental factor affecting the performance of TMPs herein.As the core of this research,“stimulatory factors”can provide numerous solutions to improve the performance of TMP materials and provide a good starting point for TMP research.
基金National Key Research Program of China(2017YFA0204800)National Natural Science Foundation of China(No.21603136)+1 种基金the National Science Basic Research Plan in Shaanxi Province of China(2017JM2007)the Fundamental Research Funds for the Central Universities(2019TS005)。
文摘Hydrogen generation via artificial photosynthesis paves a promising way to remit the ever-increasing energy crisis and deteriorative environmental issues.Among all the materials utilized for solar hydrogen production,perovskite has emerged as a rising star due to its superior optoelectronic properties.This manuscript aims to provide a comprehensive review summarizing the recent inspiring advancements on perovskite-based solar hydrogen production systems,including the particulate photocatalysis,photoelectrochemical cells,and photovoltaic-electrocatalytic cells.We start with a brief introduction of the advantages of perovskites for solar hydrogen production and the basic principles of the three most prominent solar hydrogen production systems.The representative progresses in this field are then detailed with a special emphasis on the strategies to improve the efficiency and the stability of the systems.Finally,challenges and opportunities for the further development of the PVK-based solar hydrogen production systems are presented with perspective given on outlook,performance,cost and stability.
基金financially supported by the National Natural Science Foundation of China(22002084,22072081)the China Postdoctoral Science Foundation(2020M683420)+1 种基金the Fundamental Research Funds for the Central Universities(GK202103111)the 111 Project(B21005)。
文摘Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)holds great promise in green energy conversion and storage.However,for current CO_(2) electrolyzers that rely on the oxygen evolution reaction,a large portion of the input energy is"wasted"at the anode due to the high overpotential requirement and the recovery of low-value oxygen.To make efficient use of the electricity during electrolysis,coupling CO_(2)RR with anodic alternatives that have low energy demands and/or profitable returns with high-value products is then promising.Herein,we review the latest advances in paired systems for simultaneous CO_(2) reduction and anode valorization.We start with the cases integrating CO_(2)RR with concurrent alternative oxidation,such as inorganic oxidation using chloride,sulfide,ammonia and urea,and organic oxidation using alcohols,aldehydes and primary amines.The paired systems that couple CO_(2)RR with on-site oxidative upgrading of CO_(2)-reduced chemicals are also introduced.The coupling mechanism,electrochemical performance and economic viability of these co-electrolysis systems are discussed.Thereby,we then point out the mismatch issues between the cathodic and anodic reactions regrading catalyst ability,electrolyte solution and reactant supply that will challenge the applications of these paired electrolysis systems.Opportunities to address these issues are further proposed,providing some guidance for future research.
基金support from the National Key Research Program of China (2017YFA0204800, 2016YFA0202403)the Natural Science Foundation of China (No. 21603136)+3 种基金the Changjiang Scholar and Innovative Research Team (IRT_14R33)the Fundamental Research Funds for the Central Universities (GK202003042)The 111 Project (B14041)the Chinese National 1000-Talent-Plan program are also acknowledged。
文摘Providing efficient charge transfer through the interface between the semiconductor and co-catalyst is greatly desired in photoelectrocatalytic (PEC) energy conversion.Herein,we excogitate a novel and facile means,via electrochemical activation,to successfully load the amorphous CoOOH layer architecture onto the surface of TiO_(2).Intriguingly,the as-obtained 6%CoOOH-TiO_(2)photoelectrode manifests optimal PEC performance with a high photocurrent density of 1.3 mA/cm~2,3.5 times higher than that of pristine TiO_(2).Electrochemical impedance spectroscopy (EIS),Tafel analysis and cyclic voltammetry (CV) methods show that the carrier transfer barrier within the electrode and the transition of Co^(3+)OOH to Co^(4+)OOH have the dominating effects on the PEC performance.Theoretical calculation reveals that the interface between the CoOOH and TiO_(2)improves the homogeneity of effective d-orbital electronic-transfer ability among Co sites.This research sheds light on the water oxidation reaction and the design of more favorable PEC cocatalysts.
基金the funding support from the National Natural Science Foundation of China(No.51661018)the support from National Key Research Program of China(2017YFA0204800,2016YFA0202403)+3 种基金Natural Science Foundation of China(No.21603136)the National Science Basic Research Plan in Shaanxi Province of China(2017JM2007)the Changjiang Scholar and Innovative Research Team(IRT_14R33)The 111 Project(B14041)。
文摘Nickel oxides and(oxy)hydroxides are promising replacements for noble-metal-based catalysts owing to their high activity and good long-term stability for the oxygen evolution reaction(OER). Herein, we developed nanoporous Ni by a method of combined rapid solidification and chemical dealloying. Subsequently,nanoporous Ni O was obtained via heating treatment, the macropore and skeleton sizes of the NiO originated from Ni10Al90 alloy are 100–300 nm and 80–200 nm, respectively. Benefiting from the multi-stage nanoporous structure and high specific surface area, the nanoporous NiO demonstrates an outstanding OER, reaching 20 mA cm-2 at an overpotential of 356 mV in 1 M KOH. The corresponding Tafel slope and apparent activation energy are measured to be 76.73 mV dec-1 and 29.0 kJ mol-1, respectively. Moreover,kinetic analysis indicates that the Ni O catalyst shows pseudocapacitive characteristics, and the improved current is attributed to the high-rate pseudocapacitive behavior that efficiently maintains increased nickel redox cycling to accelerate the reaction rates. After 1000 cycles of voltammetry, the overpotential of the NiO decreases by 22 mV(j = 10 mA cm-2), exhibiting excellent stability and durability.
基金the Tianjin Key Medical Discipline(Specialty)Construction Project(Grant No.TJYXZDXK-034A).
文摘Background and Aims:Further decompensation in cirrhosis is associated with increased mortality.However,reliable tools to predict further decompensation after transjugular intrahepatic portosystemic shunt(TIPS)are currently limited.This study aimed to investigate the incidence and risk factors of further decompensation within one year post-TIPS in patients with cirrhosis and to develop a predictive model for identifying high-risk individuals.Methods:This retrospective cohort study enrolled 152 patients with cirrhosis undergoing TIPS for variceal bleeding and/or refractory ascites(January 2018-January 2024).Patients were stratified according to one-year decompensation outcomes.LASSO regression and multivariable logistic analysis were used to identify predictors,and a nomogram was constructed and internally validated using bootstrapping(1,000 replicates).Results:Among the 152 patients(median age 57.5 years[IQR 50.0-66.0];58.6%male;58.6%viral/alcohol-associated etiology),65.8%(100/152)achieved clinical stability at one year post-TIPS,while 34.2%(52/152)developed further decompensation.LASSO regression identified right hepatic lobe volume,spleen volume,and portal pressure gradient(PPG)reduction as key predictors,all independently associated with further decompensation risk in multivariable analysis(OR[95%CI]:0.683[0.535-0.873],1.435[1.240-1.661],and 0.961[0.927-0.996],respectively).The nomogram demonstrated superior discrimination compared with PPG reduction alone and benchmark prognostic scores(AUC 0.854[0.792-0.915] vs.0.619-0.652;△AUC +0.201-+0.235,p<0.001)with 92.3%sensitivity.High-risk patients(score>86)had a 10.7-fold higher risk of further decompensation than lowrisk patients(60.0%vs.5.6%;p<0.0001).Conclusions:This validated model,combining hepatosplenic volumetry and PPG reduction,accurately stratifies further decompensation risk post-TIPS and may guide targeted surveillance and preventive interventions.
基金National Natural Science Foundation of China,Grant/Award Numbers:21875016,22179004Natural Science Foundation of Beijing,Grant/Award Number:2212014。
文摘High nickel content layered cathodes,represented by NCM(LiNi_(x)Co_(y)Mn_(z)O_(2),x+y+z=1),are now widely employed in the market of electric vehicles,owing to their high energy density.With the gradual increase of nickel content and capacity,the issues on cycling life and safety become more serious.In this review,various strategies for improving the performance of high nickel NCM are summarized on the aspects of surface coating,ionic doping,and singlecrystal NCM.The coating strategy was separately described according to the physical property of coating species,including inert material coating,Li^(+)-conductor coating,electronic conductor coating,and mixed conductor coating.These coating species help to suppress the interfacial oxidation of electrolytes by NCM,improving the cycling life and safety.The elemental doping in the crystal lattice of NCM is then presented in the aspects of cation,anion,and mixed-ion doping,which are beneficial to stabilize the layered structure during charge–discharge and so promote the electrochemical performance.In quite recent years,the strategy of single-crystal NCM was demonstrated to be a promising pathway,owing to the dramatically reduced surface area and grain boundary.Finally,the remaining unsolved challenges and future strategies for further development of NCM cathode materials are outlined.
