Inspired by the natural photosynthesis systems,the integrated harnessing and conversion of CO_(2) present a promising solution for addressing the ever-rising global atmospheric concentration of CO_(2).Hollow multi-she...Inspired by the natural photosynthesis systems,the integrated harnessing and conversion of CO_(2) present a promising solution for addressing the ever-rising global atmospheric concentration of CO_(2).Hollow multi-shelled structured(HoMS)photocatalysts,featuring alternating shells and cavities,have recently gained recognition as efficient nano-reactors for capturing CO_(2) molecules and facilitating effective photoreduction within these hierarchical structures,leveraging the preeminent enrichment effect.In this work,to augment the photocatalytic efficacy of HoMS in CO_(2) treatment,highly dispersed Cu_(x)O nanoparticles(NPs)were incorporated on the CeO2 shells through a polymer-assisted impregnation method to create more active sites and strengthen the interaction between the hetero-shells and CO_(2) molecules.The photoreduction of the CO_(2)-to-CO rate under a diluted CO_(2)(15%,volume fraction)atmosphere is improved by the introduction of Cu_(x)O NPs,with the highest CO yielding rate reaching 120µmol·h^(−1)·g^(−1) without any sacrificial reagents.Further comparison experiments and theoretical calculations reveal that the Cu_(x)O NPs promote the adsorption of CO_(2) molecules in HoMS,accelerate the charge transfer efficiency,and stabilize the surface oxygen vacancies(Ovs)during the photoreduction CO_(2) conversion process.We hope these easy-to-prepare HoMS nanoreactors can contribute to the effective enrichment and valorization of CO_(2) in industrial exhaust gases.展开更多
For CO catalytic oxidation,Cu and Ce species are of great importance,between which the synergistic effect is worth investigating.In this work,CeO_(2)/Cu_(2)O with Cu_(2)O{111}and{100}planes were comparatively explored...For CO catalytic oxidation,Cu and Ce species are of great importance,between which the synergistic effect is worth investigating.In this work,CeO_(2)/Cu_(2)O with Cu_(2)O{111}and{100}planes were comparatively explored on CO catalytic oxidation to reveal the effects of interfacial electronic interactions and oxygen defects.The activity result demonstrates that CeO_(2)/o-Cu_(2)O{111}has superior performance compared with CeO_(2)/c-Cu_(2)O{100}.Credit to the coordination unsaturated copper atoms(Cu_(CUS))on oCu_(2)O{111}surface,the interfacial electronic interactions on CeO_(2)/o-Cu_(2)O{111}are more obvious than those on CeO_(2)/c-Cu_(2)O{100},leading to richer oxygen defect generation,better redox and activation abilities of CO and O_(2)reactants.Furthermore,the reaction mechanism of CeO_(2)/o-Cu_(2)O{111}on CO oxidation is revealed,i.e.,CO and O_(2)are adsorbed on the Cucus on Cu_(2)O{111}and oxygen defect of CeO_(2),respectively,and then synergistically promote the CO oxidation to CO_(2).The work sheds light on the designing optimized ceria and copper-based catalysts and the mechanism of CO oxidation.展开更多
For catalytic materials,the characteristics of one-dimension and hollowness are the promotion factors for their full presentation of catalytic activity,and through a template-as sis ted method,both above superiorities...For catalytic materials,the characteristics of one-dimension and hollowness are the promotion factors for their full presentation of catalytic activity,and through a template-as sis ted method,both above superiorities can be fused simultaneously.Here,we proposed a novel strategy inspired by Pearson's principle with Cu_(2)O wires as templates,and prepared FeOOH hollow tubes,which covered by FeOOH scales.When applied as oxygen evolution reaction(OER)catalyst,the FeOOH scaly hollow tubes(FeOOH SHTs)showed outstanding catalytic activity with a low overpotential of 245 mV to drive a current density of10 mA·cm^(-2),excellent kinetics manifesting as a low Tafel slope of 46.9 mV·dec^(-1),and robust stability.This work provides a new synthesis strategy for an ideal OER catalyst,FeOOH,with high inherent activity and enhances the feasibility to broaden the design ideas of transition metalbased catalysts.展开更多
Construction of photocatalysts with a Schottky heterojunction could realize highly efficient and stable degradation of organic pollutes in the wastewater.In this work,a precipitation method was used to prepare Ti_(3)C...Construction of photocatalysts with a Schottky heterojunction could realize highly efficient and stable degradation of organic pollutes in the wastewater.In this work,a precipitation method was used to prepare Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite photocatalysts with the Schottky heterojunction for the decomposition of tetracycline(TC)antibiotics under visible light.As-prepared photocatalysts were characterized by various techniques such as X-ray diffraction analysis(XRD),High resolution transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).When the best Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite was applied for the degradation of TC under visible light,the degradation efficiency reached up to 97.6%only in 50 min.It is considered that superoxide radical(O_(2)^(→))and hole(h^(+))were the main reactive species for the TC degradation,and in the Schottky heterojunction,e^(-)-h^(+)pairs in the catalyst could be transferred and separated effectively,resulting in obviously enhanced photocatalytic efficiency and stability.展开更多
Co3 O4 is one of the most studied transition-metal oxides for use in energy-storage devices.However,its poor conductivity and stability limit its application.In this study,a facile method for anchoring Co3 O4-encapsul...Co3 O4 is one of the most studied transition-metal oxides for use in energy-storage devices.However,its poor conductivity and stability limit its application.In this study,a facile method for anchoring Co3 O4-encapsulated Cu2 O nanocubes on porous carbon(PC) to form Cu2 O@Co3 O4/PC was developed.The Cu2 O@Co3 O4/PC composite exhibited superior electrochemical performance as a supercapacitor electrode material.The resultant supercapacitor delivered high specific capacitance(1096 F g^-1 at 1 A g^-1),high rate capability(83 % retention at 10 A g^-1),and excellent cycling stability(95 % retention of initial capacitance after 3000 cycles).Moreover,an asymmetric supercapacitor fabricated by coupling a Cu2 O@Co3 O4/PC positive electrode with a reduced graphene oxide negative electrode exhibited high energy density(32.1 W h kg^-1 at 700 W kg^-1).Thus,our results demonstrate that Cu2 O@Co3 O4/PC is a promising electrode material for energy-storage devices.展开更多
基金This work was supported by the National Natural Science Foundation of China(Nos.51932001,52272097,and 52372170)the Beijing Natural Science Foundation,China(Nos.2242019 and 2232068)the National Key Research and Development Program of China(No.2018YFA0703503).
文摘Inspired by the natural photosynthesis systems,the integrated harnessing and conversion of CO_(2) present a promising solution for addressing the ever-rising global atmospheric concentration of CO_(2).Hollow multi-shelled structured(HoMS)photocatalysts,featuring alternating shells and cavities,have recently gained recognition as efficient nano-reactors for capturing CO_(2) molecules and facilitating effective photoreduction within these hierarchical structures,leveraging the preeminent enrichment effect.In this work,to augment the photocatalytic efficacy of HoMS in CO_(2) treatment,highly dispersed Cu_(x)O nanoparticles(NPs)were incorporated on the CeO2 shells through a polymer-assisted impregnation method to create more active sites and strengthen the interaction between the hetero-shells and CO_(2) molecules.The photoreduction of the CO_(2)-to-CO rate under a diluted CO_(2)(15%,volume fraction)atmosphere is improved by the introduction of Cu_(x)O NPs,with the highest CO yielding rate reaching 120µmol·h^(−1)·g^(−1) without any sacrificial reagents.Further comparison experiments and theoretical calculations reveal that the Cu_(x)O NPs promote the adsorption of CO_(2) molecules in HoMS,accelerate the charge transfer efficiency,and stabilize the surface oxygen vacancies(Ovs)during the photoreduction CO_(2) conversion process.We hope these easy-to-prepare HoMS nanoreactors can contribute to the effective enrichment and valorization of CO_(2) in industrial exhaust gases.
基金Project supported by the National Natural Science Foundation of China(21707066,21677069)。
文摘For CO catalytic oxidation,Cu and Ce species are of great importance,between which the synergistic effect is worth investigating.In this work,CeO_(2)/Cu_(2)O with Cu_(2)O{111}and{100}planes were comparatively explored on CO catalytic oxidation to reveal the effects of interfacial electronic interactions and oxygen defects.The activity result demonstrates that CeO_(2)/o-Cu_(2)O{111}has superior performance compared with CeO_(2)/c-Cu_(2)O{100}.Credit to the coordination unsaturated copper atoms(Cu_(CUS))on oCu_(2)O{111}surface,the interfacial electronic interactions on CeO_(2)/o-Cu_(2)O{111}are more obvious than those on CeO_(2)/c-Cu_(2)O{100},leading to richer oxygen defect generation,better redox and activation abilities of CO and O_(2)reactants.Furthermore,the reaction mechanism of CeO_(2)/o-Cu_(2)O{111}on CO oxidation is revealed,i.e.,CO and O_(2)are adsorbed on the Cucus on Cu_(2)O{111}and oxygen defect of CeO_(2),respectively,and then synergistically promote the CO oxidation to CO_(2).The work sheds light on the designing optimized ceria and copper-based catalysts and the mechanism of CO oxidation.
基金financially supported by the National Key Research and Development Program of China(No.2018YFA0703700)the National Natural Science Foundation of China(Nos.12004031,12034002 and 51971025)+3 种基金Beijing Natural Science Foundation(No.2212034)Foshan Talents Special Foundation(No.BKBS202003)the Scientific and Technological Innovation Foundation of Foshan(No.BK22BE005)Foshan Science and Technology Innovation Project(No.2018IT100363)。
文摘For catalytic materials,the characteristics of one-dimension and hollowness are the promotion factors for their full presentation of catalytic activity,and through a template-as sis ted method,both above superiorities can be fused simultaneously.Here,we proposed a novel strategy inspired by Pearson's principle with Cu_(2)O wires as templates,and prepared FeOOH hollow tubes,which covered by FeOOH scales.When applied as oxygen evolution reaction(OER)catalyst,the FeOOH scaly hollow tubes(FeOOH SHTs)showed outstanding catalytic activity with a low overpotential of 245 mV to drive a current density of10 mA·cm^(-2),excellent kinetics manifesting as a low Tafel slope of 46.9 mV·dec^(-1),and robust stability.This work provides a new synthesis strategy for an ideal OER catalyst,FeOOH,with high inherent activity and enhances the feasibility to broaden the design ideas of transition metalbased catalysts.
基金supported by the Natural Science Foundation of Shanxi Province,China(201901D111308)Hirosaki University Fund.
文摘Construction of photocatalysts with a Schottky heterojunction could realize highly efficient and stable degradation of organic pollutes in the wastewater.In this work,a precipitation method was used to prepare Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite photocatalysts with the Schottky heterojunction for the decomposition of tetracycline(TC)antibiotics under visible light.As-prepared photocatalysts were characterized by various techniques such as X-ray diffraction analysis(XRD),High resolution transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).When the best Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite was applied for the degradation of TC under visible light,the degradation efficiency reached up to 97.6%only in 50 min.It is considered that superoxide radical(O_(2)^(→))and hole(h^(+))were the main reactive species for the TC degradation,and in the Schottky heterojunction,e^(-)-h^(+)pairs in the catalyst could be transferred and separated effectively,resulting in obviously enhanced photocatalytic efficiency and stability.
基金This work was supported by the National Natural Science Foundation of China(Nos.51861005 and 51861004)the Innovation Project of Guangxi Graduate Education(No.YCSW2019149)the Guangxi Natural Science Foundation(No.2017GXNSFDA198018)。
文摘Co3 O4 is one of the most studied transition-metal oxides for use in energy-storage devices.However,its poor conductivity and stability limit its application.In this study,a facile method for anchoring Co3 O4-encapsulated Cu2 O nanocubes on porous carbon(PC) to form Cu2 O@Co3 O4/PC was developed.The Cu2 O@Co3 O4/PC composite exhibited superior electrochemical performance as a supercapacitor electrode material.The resultant supercapacitor delivered high specific capacitance(1096 F g^-1 at 1 A g^-1),high rate capability(83 % retention at 10 A g^-1),and excellent cycling stability(95 % retention of initial capacitance after 3000 cycles).Moreover,an asymmetric supercapacitor fabricated by coupling a Cu2 O@Co3 O4/PC positive electrode with a reduced graphene oxide negative electrode exhibited high energy density(32.1 W h kg^-1 at 700 W kg^-1).Thus,our results demonstrate that Cu2 O@Co3 O4/PC is a promising electrode material for energy-storage devices.