The increasing demands of hydrogen and the recent discovery of large reserves of methane have prompted the conversion of methane to hydrogen.The challenges raised by intensive CO_(2) emission from the traditional conv...The increasing demands of hydrogen and the recent discovery of large reserves of methane have prompted the conversion of methane to hydrogen.The challenges raised by intensive CO_(2) emission from the traditional conversion of methane have provoked emission-free hydrogen production from methane.The catalytic decomposition of methane(CDM) to produce hydrogen and advanced carbon hence comes into consideration due to the short process and environmental benignity.Although many researchers have made considerable progress in CDM research on the laboratory scale,CDM is still in its infancy in industrialization.The history of its development,fundamental mechanisms,and recent research progress in catalysts and catalytic systems are herein highlighted.The problems of catalytic interface degradation are reviewed,focusing on deactivation from coke deposition in the CDM process.The introduction of a liquid phase interface which can in-situ remove carbon products provides a new strategy for this process.Furthermore,the challenges and prospects for future research into novel CDM catalysts or catalyst systems are included.展开更多
Implementation of non-precious electrocatalysts is key-enabling for water electrolysis to relieve challenges in energy and environmental sustainability. Self-supporting Ni-V2O3 electrodes consisting of nanostrip-like ...Implementation of non-precious electrocatalysts is key-enabling for water electrolysis to relieve challenges in energy and environmental sustainability. Self-supporting Ni-V2O3 electrodes consisting of nanostrip-like V2O3 perpendicularly anchored on Ni meshes are herein constructed via the electrochemical reduction of soluble NaVO3 in molten salts for enhanced electrocatalytic hydrogen evolution. Such a special configuration in morphology and composition creates a well confined interface between Ni and V2O3. Experimental and Density-Functional-Theory results confirm that the synergy between Ni and V2O3 accelerates the dissociation of H2O for forming hydrogen intermediates and enhances the combination of H*for generating H2.展开更多
Direct conversion of biomass to functional materials is an ideal solution to relieve challenges in environmental and energy sustainability.We herein demonstrate a molten salt thermoelectrolysis of rice husks(RHs)mainl...Direct conversion of biomass to functional materials is an ideal solution to relieve challenges in environmental and energy sustainability.We herein demonstrate a molten salt thermoelectrolysis of rice husks(RHs)mainly consisting of organic mass and biosilica to achieve high-efficiency and upgraded utilization of both Si and C in RHs.By coupling pyrolysis of organic mass with electrochemical reduction of silica in molten salts,the thermoelectrolysis of RHs in molten CaCl_(2)-NaCl at 800℃ refines the RHs and acidleached RHs to SiC nanowire/C(SiC-NW/C)and Si nanoparticle/C(Si-NP/C),respectively.The present study highlights the molten salt thermoelectrolysis for reclamation of biomass wastes in an affordable and controllable manner.展开更多
Structural and compositional design of core-shell structure is an effective strategy towards enhanced catalysis.Herein,amorphous MnO2 nanosheets and K+-intercalated layered MnO2 nanosheets are controllably assembled o...Structural and compositional design of core-shell structure is an effective strategy towards enhanced catalysis.Herein,amorphous MnO2 nanosheets and K+-intercalated layered MnO2 nanosheets are controllably assembled over Fe2O3 spindles,in which the MnO2 nanosheets are perpendicularly anchored to the surface of Fe2O3.Such a core shell structure contributes to a high specific surface area and abundant pore channels on the surface of catalysts.In addition,the existence of K+provides large numbers of basic sites and restrains the formation of unpleasant(Fe1-xMnx)3O4.Benefiting from the merits in structure and composition,CO adsorption is enhanced and remaining time of intermediates is prolonged on the surfaces of catalysts during the Fischer–Tropsch synthesis(FTS),facilitating to the formation of active iron carbides and C–C coupling reactions.Resultantly,the Fe2O3@K+-Mn O2 shows both a high CO conversion of 82.3%and a high C5+ selectivity of 73.1%.The present study provides structural and compositional rationales on design high-performance catalysts towards FTS.展开更多
Heteroatom-doped porous carbon materials are very attractive for lithium ion batteries(LIBs) owing to their high specific surface areas, open pore structures, and abundant active sites. However, heteroatomdoped porous...Heteroatom-doped porous carbon materials are very attractive for lithium ion batteries(LIBs) owing to their high specific surface areas, open pore structures, and abundant active sites. However, heteroatomdoped porous carbon with very high surface area and large pore volume are highly desirable but still remain a big challenge. Herein, we reported a sulfur-doped mesoporous carbon(CMK-5-S) with nanotubes array structure, ultrahigh specific surface area(1390 m^(2)/g), large pore volume(1.8 cm^(3)/g), bimodal pore size distribution(2.9 and 4.6 nm), and high sulfur content(2.5 at%). The CMK-5-S used as an anode material for LIBs displays high specific capacity, excellent rate capability and highly cycling stability. The initial reversible specific capacity at 0.1 A/g is as high as 1580 mAh/g and simultaneously up to 701 mAh/g at 1A/g even after 500 cycles. Further analysis reveals that the excellent electrochemical storage performances is attributed to its unique structures as well as the expanded lattice by sulfur-doping.展开更多
CO oxidation is a benchmark in heterogeneous catalysis for evaluation of redox catalysts due to its practical relevance in many applications and the fundamental problems associated with its very high activity at low t...CO oxidation is a benchmark in heterogeneous catalysis for evaluation of redox catalysts due to its practical relevance in many applications and the fundamental problems associated with its very high activity at low temperatures.Among which,Co_(3)O_(4) is one of the most active non-precious metal catalysts.Exposed crystal planes and cobalt sites are considered to be important for its high catalytic activity.Herein,we demonstrate an enhanced CO oxidation activity by a defect-rich mesoporous Co_(3)O_(4) that prepared by a designed dual-template method.Two different kinds of silicas are used as hard-templates at the same time,resulting in a defect-rich mesoporous Co_(3)O_(4) with a surface area as high as 169 m^(2)/g.This catalyst exhibited a very high catalytic activity for low temperature CO oxidation with a light-off temperature at -73℃ under the space velocity of 80,000 mL h^(-1)g^(-1)_(cat).Further studies reveal that the high surface area promotes the lattice oxygen mobility,surface rich of Co^(2+)species and active oxygen species are crucial for the high catalytic activity.Moreover,the dual-template approach paves a way towards the design and construction of high-surface-area mesoporous metal oxides for various applications.展开更多
Excitonic confinement greatly determines the charge carrier transport of photocatalysts.A molten salt modulation of excitonic con-finement is herein demonstrated as formation of ultrafine carbon-doped anatase TiO_(2)w...Excitonic confinement greatly determines the charge carrier transport of photocatalysts.A molten salt modulation of excitonic con-finement is herein demonstrated as formation of ultrafine carbon-doped anatase TiO_(2)with grafted graphitic carbon nitride,which is rationalized as an excellent catalyst for overall CO_(2)photoreduction.Compared with bulk TiO_(2),the carbon-doped TiO_(2)(M-TiO_(2))pos-sesses a weaker excitonic confinement to decrease exciton binding energy from 99 to 58 meV,consequently enhancing free-charge-carrier generation and transportation.Effective Z-scheme electron transfer from M-TiO_(2)to C_(3)N_(4) is built,enhancing the CO_(2)conversion via the synchronous optimization of redox ability,CO_(2)activation,and^(*)COOH generation.This work highlights the unique chemistry of excitonic dissociation on facilitating separation of electron and hole,and also extends the scope of molten salt-mediated modulation of photocatalysis materials.展开更多
Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need ...Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need to be improved.Herein,we report the rational fabrication of well-defined Ag_(24)Au cluster decorated highly ordered nanorod-like mesoporous Co_(3)O_(4)(Ag_(24)Au/mesoCo_(3)O_(4))for highly efficient and selective CO_(2)hydrogenation.The orderly assembled meso-Co_(3)O_(4)nanorods were prepared via a nanocasting method,offering large surface area and abundant active sites for CO_(2)adsorption and conversion.Moreover,the catalytic activity and selectivity were further improved by molecule-like Ag_(24)Au cluster decoration and reaction temperature optimization.The Ag_(24)Au/meso-Co_(3)O_(4)composite catalyst exhibited an ultrahigh CH_(4)yield rate of 204 mmol·g^(−1)·h^(−1)and a greatly improved CH_(4)selectivity of 82%for CO_(2)hydrogenation,significantly higher than those of pristine meso-Co_(3)O_(4)catalyst.The mechanism of the photothermal catalytic performance improvement was verified by CO_(2)temperature-programmed desorption and time-resolved transient photoluminescence,revealing that CO_(2)molecules underwent a vigorous adsorption and rapid activation process over Ag_(24)Au/meso-Co_(3)O_(4).The hot electrons created by the localized surface plasmon resonance effect of Ag_(24)Au clusters facilitated the charge transfer for subsequent multi-electron CO_(2)hydrogeneration processes,resulting in a significant increase in the productivity and selectivity for CO_(2)-to-CH_(4)conversion.This work suggests that the rational coupling of well-defined metal atom clusters and ordered transition metal compound nanostructures could open a new avenue towards photoinduced green chemistry processes for efficient CO_(2)recycling and reutilization.展开更多
Ordered mesoporous Cu-Mg-A1 composite oxides were synthesized via the one-pot evaporation-in- duced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous sp...Ordered mesoporous Cu-Mg-A1 composite oxides were synthesized via the one-pot evaporation-in- duced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous spinel matrix. After H2 reduction treatment, according to X-ray diffraction (XRD) and transmission electron microscopy (TEM) results, copper existed as metallic nanoparticles with the size of 6-10 nm that well decorated the parent mesoporous skeleton. The metallic nanoparticles were then re-oxidized to copper oxide when exposed to air or during CO oxidation reaction at low temperatures. Thus, copper migrated from bulk spinel phase to the surface after the reduction-oxidation treat- ment. Moreover, the copper on the surface was re-incor- porated into the bulk spinel phase by further thermal treatment at much higher temperature in the presence of air. The correlation between the state of copper in the mesoporous composite oxides and the catalytic perfor- mance toward CO oxidation was studied. It was found that copper existed as oxide nanoparticles on the surface of mesoporous Mg-Al skeleton is much more active than that existed as lattice Cu ions in spinel phase.展开更多
基金the funding support from the National Natural Science Foundation of China(51722404,51674177,51804221 and 91845113)the National Key R&D Program of China(2018YFE0201703)+2 种基金the China Postdoctoral Science Foundation(2018M642906 and 2019T120684)the Fundamental Research Funds for the Central Universities(2042019kf0230)the Hubei Provincial Natural Science Foundation of China(2019CFA065)。
文摘The increasing demands of hydrogen and the recent discovery of large reserves of methane have prompted the conversion of methane to hydrogen.The challenges raised by intensive CO_(2) emission from the traditional conversion of methane have provoked emission-free hydrogen production from methane.The catalytic decomposition of methane(CDM) to produce hydrogen and advanced carbon hence comes into consideration due to the short process and environmental benignity.Although many researchers have made considerable progress in CDM research on the laboratory scale,CDM is still in its infancy in industrialization.The history of its development,fundamental mechanisms,and recent research progress in catalysts and catalytic systems are herein highlighted.The problems of catalytic interface degradation are reviewed,focusing on deactivation from coke deposition in the CDM process.The introduction of a liquid phase interface which can in-situ remove carbon products provides a new strategy for this process.Furthermore,the challenges and prospects for future research into novel CDM catalysts or catalyst systems are included.
基金the funding support from the National Natural Science Foundation of China(51722404,51674177,51804221 and 91845113)the National Key R&D Program of China(2018YFE0201703)+2 种基金the China Postdoctoral Science Foundation(2018M642906 and 2019T120684)the Fundamental Research Funds for the Central Universities(2042017kf0200)the Hubei Provincial Natural Science Foundation of China(2019CFA065)。
文摘Implementation of non-precious electrocatalysts is key-enabling for water electrolysis to relieve challenges in energy and environmental sustainability. Self-supporting Ni-V2O3 electrodes consisting of nanostrip-like V2O3 perpendicularly anchored on Ni meshes are herein constructed via the electrochemical reduction of soluble NaVO3 in molten salts for enhanced electrocatalytic hydrogen evolution. Such a special configuration in morphology and composition creates a well confined interface between Ni and V2O3. Experimental and Density-Functional-Theory results confirm that the synergy between Ni and V2O3 accelerates the dissociation of H2O for forming hydrogen intermediates and enhances the combination of H*for generating H2.
基金the funding support from the National Natural Science Foundation of China(51722404,51674177,51804221 and 91845113)the National Key R&D Program of China(2018YFE0201703)+2 种基金the China Postdoctoral Science Foundation(2018M642906 and 2019T120684)the Fundamental Research Funds for the Central Universities(2042017kf0200)the Hubei Provincial Natural Science Foundation of China(2019CFA065)。
文摘Direct conversion of biomass to functional materials is an ideal solution to relieve challenges in environmental and energy sustainability.We herein demonstrate a molten salt thermoelectrolysis of rice husks(RHs)mainly consisting of organic mass and biosilica to achieve high-efficiency and upgraded utilization of both Si and C in RHs.By coupling pyrolysis of organic mass with electrochemical reduction of silica in molten salts,the thermoelectrolysis of RHs in molten CaCl_(2)-NaCl at 800℃ refines the RHs and acidleached RHs to SiC nanowire/C(SiC-NW/C)and Si nanoparticle/C(Si-NP/C),respectively.The present study highlights the molten salt thermoelectrolysis for reclamation of biomass wastes in an affordable and controllable manner.
基金funding support from the National Natural Science Foundation of China (51722404, 51674177, 91845113 and 51804221)the “1000-Youth Talents Plan”+3 种基金the Fundamental Research Funds for the Central Universities (2042017kf0200)National Key R&D Program of China (2018YFE0201703)the China Postdoctoral Science Foundation (2018M642906 and 2019T120684)Hubei Provincial Natural Science Foundation of China (2019CFA065)。
文摘Structural and compositional design of core-shell structure is an effective strategy towards enhanced catalysis.Herein,amorphous MnO2 nanosheets and K+-intercalated layered MnO2 nanosheets are controllably assembled over Fe2O3 spindles,in which the MnO2 nanosheets are perpendicularly anchored to the surface of Fe2O3.Such a core shell structure contributes to a high specific surface area and abundant pore channels on the surface of catalysts.In addition,the existence of K+provides large numbers of basic sites and restrains the formation of unpleasant(Fe1-xMnx)3O4.Benefiting from the merits in structure and composition,CO adsorption is enhanced and remaining time of intermediates is prolonged on the surfaces of catalysts during the Fischer–Tropsch synthesis(FTS),facilitating to the formation of active iron carbides and C–C coupling reactions.Resultantly,the Fe2O3@K+-Mn O2 shows both a high CO conversion of 82.3%and a high C5+ selectivity of 73.1%.The present study provides structural and compositional rationales on design high-performance catalysts towards FTS.
基金funding from the National Key R&D Program of China (No. 2018YFE0201703)the National Natural Science Foundation of China (Nos. 22272120, U2202251)the “1000-Youth Talents Plan”。
文摘Heteroatom-doped porous carbon materials are very attractive for lithium ion batteries(LIBs) owing to their high specific surface areas, open pore structures, and abundant active sites. However, heteroatomdoped porous carbon with very high surface area and large pore volume are highly desirable but still remain a big challenge. Herein, we reported a sulfur-doped mesoporous carbon(CMK-5-S) with nanotubes array structure, ultrahigh specific surface area(1390 m^(2)/g), large pore volume(1.8 cm^(3)/g), bimodal pore size distribution(2.9 and 4.6 nm), and high sulfur content(2.5 at%). The CMK-5-S used as an anode material for LIBs displays high specific capacity, excellent rate capability and highly cycling stability. The initial reversible specific capacity at 0.1 A/g is as high as 1580 mAh/g and simultaneously up to 701 mAh/g at 1A/g even after 500 cycles. Further analysis reveals that the excellent electrochemical storage performances is attributed to its unique structures as well as the expanded lattice by sulfur-doping.
基金funding from the National Key R&D Program of China (No. 2018YFE0201703)the “1000-Youth Talents Plan”the Fundamental Research Funds for the Central Universities (No. 2042019kf0230)。
文摘CO oxidation is a benchmark in heterogeneous catalysis for evaluation of redox catalysts due to its practical relevance in many applications and the fundamental problems associated with its very high activity at low temperatures.Among which,Co_(3)O_(4) is one of the most active non-precious metal catalysts.Exposed crystal planes and cobalt sites are considered to be important for its high catalytic activity.Herein,we demonstrate an enhanced CO oxidation activity by a defect-rich mesoporous Co_(3)O_(4) that prepared by a designed dual-template method.Two different kinds of silicas are used as hard-templates at the same time,resulting in a defect-rich mesoporous Co_(3)O_(4) with a surface area as high as 169 m^(2)/g.This catalyst exhibited a very high catalytic activity for low temperature CO oxidation with a light-off temperature at -73℃ under the space velocity of 80,000 mL h^(-1)g^(-1)_(cat).Further studies reveal that the high surface area promotes the lattice oxygen mobility,surface rich of Co^(2+)species and active oxygen species are crucial for the high catalytic activity.Moreover,the dual-template approach paves a way towards the design and construction of high-surface-area mesoporous metal oxides for various applications.
基金funding support from the National Natural Science Foundation of China(22272120,U2202251,92045302)the Fundamental Research Funds for the Central Universities(2042022kf1174,2042021kf0213)+1 种基金the Hainan Province Science and Technology Special Fund(ZDYF2021SHFZ058,ZDYF2020207)the High-level Talent Project of Hainan Natural Science Foundation(2019RC075).
文摘Excitonic confinement greatly determines the charge carrier transport of photocatalysts.A molten salt modulation of excitonic con-finement is herein demonstrated as formation of ultrafine carbon-doped anatase TiO_(2)with grafted graphitic carbon nitride,which is rationalized as an excellent catalyst for overall CO_(2)photoreduction.Compared with bulk TiO_(2),the carbon-doped TiO_(2)(M-TiO_(2))pos-sesses a weaker excitonic confinement to decrease exciton binding energy from 99 to 58 meV,consequently enhancing free-charge-carrier generation and transportation.Effective Z-scheme electron transfer from M-TiO_(2)to C_(3)N_(4) is built,enhancing the CO_(2)conversion via the synchronous optimization of redox ability,CO_(2)activation,and^(*)COOH generation.This work highlights the unique chemistry of excitonic dissociation on facilitating separation of electron and hole,and also extends the scope of molten salt-mediated modulation of photocatalysis materials.
基金supports from the National Key Research&Development Program of China(No.2017YFA0208200)the National Natural Science Foundation of China(Nos.22022505 and 21872069)+1 种基金the Fundamental Research Funds for the Central Universities(No.0205-14380266)the 2021 Suzhou Gusu Leading Talents of Science and Technology Innovation and Entrepreneurship in Wujiang District.
文摘Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need to be improved.Herein,we report the rational fabrication of well-defined Ag_(24)Au cluster decorated highly ordered nanorod-like mesoporous Co_(3)O_(4)(Ag_(24)Au/mesoCo_(3)O_(4))for highly efficient and selective CO_(2)hydrogenation.The orderly assembled meso-Co_(3)O_(4)nanorods were prepared via a nanocasting method,offering large surface area and abundant active sites for CO_(2)adsorption and conversion.Moreover,the catalytic activity and selectivity were further improved by molecule-like Ag_(24)Au cluster decoration and reaction temperature optimization.The Ag_(24)Au/meso-Co_(3)O_(4)composite catalyst exhibited an ultrahigh CH_(4)yield rate of 204 mmol·g^(−1)·h^(−1)and a greatly improved CH_(4)selectivity of 82%for CO_(2)hydrogenation,significantly higher than those of pristine meso-Co_(3)O_(4)catalyst.The mechanism of the photothermal catalytic performance improvement was verified by CO_(2)temperature-programmed desorption and time-resolved transient photoluminescence,revealing that CO_(2)molecules underwent a vigorous adsorption and rapid activation process over Ag_(24)Au/meso-Co_(3)O_(4).The hot electrons created by the localized surface plasmon resonance effect of Ag_(24)Au clusters facilitated the charge transfer for subsequent multi-electron CO_(2)hydrogeneration processes,resulting in a significant increase in the productivity and selectivity for CO_(2)-to-CH_(4)conversion.This work suggests that the rational coupling of well-defined metal atom clusters and ordered transition metal compound nanostructures could open a new avenue towards photoinduced green chemistry processes for efficient CO_(2)recycling and reutilization.
基金This work was supported by the Recruitment Program of Global Youth Experts of China, the National Natural Science Foundation of China (21403267, 21450110410), and Shandong Postdoctoral Innovation Program (201303065).
文摘Ordered mesoporous Cu-Mg-A1 composite oxides were synthesized via the one-pot evaporation-in- duced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous spinel matrix. After H2 reduction treatment, according to X-ray diffraction (XRD) and transmission electron microscopy (TEM) results, copper existed as metallic nanoparticles with the size of 6-10 nm that well decorated the parent mesoporous skeleton. The metallic nanoparticles were then re-oxidized to copper oxide when exposed to air or during CO oxidation reaction at low temperatures. Thus, copper migrated from bulk spinel phase to the surface after the reduction-oxidation treat- ment. Moreover, the copper on the surface was re-incor- porated into the bulk spinel phase by further thermal treatment at much higher temperature in the presence of air. The correlation between the state of copper in the mesoporous composite oxides and the catalytic perfor- mance toward CO oxidation was studied. It was found that copper existed as oxide nanoparticles on the surface of mesoporous Mg-Al skeleton is much more active than that existed as lattice Cu ions in spinel phase.