Effective electrocatalysis is crucial for enhancing the efficiency of water splitting to obtain clean fuels.Herein,we report a system of interesting and high-performance Sr-doped perovskite electrocatalysts with porou...Effective electrocatalysis is crucial for enhancing the efficiency of water splitting to obtain clean fuels.Herein,we report a system of interesting and high-performance Sr-doped perovskite electrocatalysts with porous structures,obtained via a facile molten salt method and applied in the oxygen evolution reaction(OER).With increasing the Sr content,the valence states of Co and Fe ions do not clearly increase,according to the Co-L2,3 and Fe-L2,3 as well as the Co-K and the Fe-K X-ray absorption spectroscopy,whereas doped holes are clearly observed in the 0-K edge.High-resolution transmission electron microscopy indicates the appearance of an amorphous layer after the electrochemical reaction.We conclude that the formation of the amorphous layer at the surface,induced by Sr doping,is crucial for achieving high OER activity,and we offer insights into the self-reconstruction of the OER catalyst.展开更多
The AEI cavity of SAPO-18 catalyst was modified with zinc cations with the conventional ion exchange procedure.The cavity modification effectively tunes the product selectivity,and shifts the products from mainly prop...The AEI cavity of SAPO-18 catalyst was modified with zinc cations with the conventional ion exchange procedure.The cavity modification effectively tunes the product selectivity,and shifts the products from mainly propylene to comparable production of ethylene and propylene in methanol to olefin(MTO)reaction.The incorporation of zinc ions and the generation of bicyclic aromatic species in the AEI cavity of SAPO-18 catalysts introduce additional diffusion hindrance that exert greater influence on the relatively bulky products(e.g.propylene and higher olefins),which increase the selectivity to small-sized products(e.g.ethylene).It appears that the incorporated zinc cations facilitate the generation of lower methylbenzenes which promote the generation of ethylene.The cavity modification via incorporating zinc ions effectively tunes the product selectivity over SAPO molecular sieves with relatively larger cavity,which provides a novel strategy to develop the potential alternative to SAPO-34 catalysts for industrial MTO reaction.展开更多
Photocatalytic Z-scheme water splitting is considered as a promising approach to produce solar hydrogen.However,the forward hydrogen production reaction is often impeded by backward reactions.In the present study,in a...Photocatalytic Z-scheme water splitting is considered as a promising approach to produce solar hydrogen.However,the forward hydrogen production reaction is often impeded by backward reactions.In the present study,in a photosystem Ⅱ-integrated hybrid Z-scheme water splitting system,the backward hydrogen oxidation reaction was significantly suppressed by loading a PtCrOx cocatalyst on a ZrO2/TaON photocatalyst.Due to the weak chemisorption and activation of molecular hydrogen on PtCrOx,where Pt is stabilized in the oxidized forms,Pt^Ⅱ and Pt^Ⅳ,hydrogen oxidation is inhibited.However,it is remarkably well-catalyzed by the metallic Pt cocatalyst,thereby rapidly consuming the produced hydrogen.This work describes an approach to inhibit the backward reaction in the photosystem Ⅱ-integrated hybrid Z-scheme water splitting system using Fe(CN)6^3-/Fe(CN)6^4-redox couple as an electron shuttle.展开更多
基金supported by the “Transformational Technologies for clean Energy and Demonstration”,Strategic Priority Research Program of the Chinese Academy of Sciences(XDA2100000)the Youth Innovation Promotion Association,Chinese Academy of Sciences(2014237)+1 种基金the National Natural Science Foundation of China(21876183)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(YJKYYQ20180066)~~
文摘Effective electrocatalysis is crucial for enhancing the efficiency of water splitting to obtain clean fuels.Herein,we report a system of interesting and high-performance Sr-doped perovskite electrocatalysts with porous structures,obtained via a facile molten salt method and applied in the oxygen evolution reaction(OER).With increasing the Sr content,the valence states of Co and Fe ions do not clearly increase,according to the Co-L2,3 and Fe-L2,3 as well as the Co-K and the Fe-K X-ray absorption spectroscopy,whereas doped holes are clearly observed in the 0-K edge.High-resolution transmission electron microscopy indicates the appearance of an amorphous layer after the electrochemical reaction.We conclude that the formation of the amorphous layer at the surface,induced by Sr doping,is crucial for achieving high OER activity,and we offer insights into the self-reconstruction of the OER catalyst.
基金supported by the Key Research Program of Frontier Sciences,CAS(QYZDY-SSW-JSC024)the Youth Innovation Promotion Association of the CAS(2014165)the National Natural Science Foundation of China(21603223,21473182,91334205,91545104)~~
文摘The AEI cavity of SAPO-18 catalyst was modified with zinc cations with the conventional ion exchange procedure.The cavity modification effectively tunes the product selectivity,and shifts the products from mainly propylene to comparable production of ethylene and propylene in methanol to olefin(MTO)reaction.The incorporation of zinc ions and the generation of bicyclic aromatic species in the AEI cavity of SAPO-18 catalysts introduce additional diffusion hindrance that exert greater influence on the relatively bulky products(e.g.propylene and higher olefins),which increase the selectivity to small-sized products(e.g.ethylene).It appears that the incorporated zinc cations facilitate the generation of lower methylbenzenes which promote the generation of ethylene.The cavity modification via incorporating zinc ions effectively tunes the product selectivity over SAPO molecular sieves with relatively larger cavity,which provides a novel strategy to develop the potential alternative to SAPO-34 catalysts for industrial MTO reaction.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB17000000)the Key Research Program of Frontier Sciences,CAS(QYZDY-SSW-JSC023)+1 种基金the National Natural Science Foundation of China(21603224,31470339)the National Key R&D Program of China(2017YFA0503700)~~
文摘Photocatalytic Z-scheme water splitting is considered as a promising approach to produce solar hydrogen.However,the forward hydrogen production reaction is often impeded by backward reactions.In the present study,in a photosystem Ⅱ-integrated hybrid Z-scheme water splitting system,the backward hydrogen oxidation reaction was significantly suppressed by loading a PtCrOx cocatalyst on a ZrO2/TaON photocatalyst.Due to the weak chemisorption and activation of molecular hydrogen on PtCrOx,where Pt is stabilized in the oxidized forms,Pt^Ⅱ and Pt^Ⅳ,hydrogen oxidation is inhibited.However,it is remarkably well-catalyzed by the metallic Pt cocatalyst,thereby rapidly consuming the produced hydrogen.This work describes an approach to inhibit the backward reaction in the photosystem Ⅱ-integrated hybrid Z-scheme water splitting system using Fe(CN)6^3-/Fe(CN)6^4-redox couple as an electron shuttle.
