Accelerating light-induced carrier transfer and improving charge utilization are essential for enhancing the efficiency of solar hydrogen production.In this work,for the first time,2D/2D covalent organicframework(COF)...Accelerating light-induced carrier transfer and improving charge utilization are essential for enhancing the efficiency of solar hydrogen production.In this work,for the first time,2D/2D covalent organicframework(COF)/SnNb_(2)O_(6)nanosheets were fabricated by a hydrothermal process.By adjusting the content of TpPa-2-COF,it was used to optimize the performance of solar hydrogen production.The optimal TpPa-2-COF/SnNb_(2)O_(6)nanosheets show a hydrogen production rate of 7.66μmol·h^(−1),which is 5.8-fold and 3.5-fold that of pristine SnNb_(2)O_(6)and TpPa-2-COF,respectively.The significant improvement in the photocatalytic performance can be attributed to the formation of a 2D/2D heterojunction nanosheet with a good energy band position between TpPa-2-COF and SnNb_(2)O_(6),which can efficaciously inhibit the restructuring of charge carriers.Through photoelectrochemical analysis,it is further proved that the interface interaction between TpPa-2-COF and SnNb_(2)O_(6)can lead to effective charge separation.Moreover,the cycling experiments reveal that the as-prepared photocatalyst has excellent stability and recycling performance.This study shows that the smart integration of organic(COF)and inorganic materials into a heterojunction with a 2D/2D structure is an available tactic for the fabrication of efficient photocatalysts.展开更多
Currently,the investigation of two-dimensional(2D)crystalline materials,notably transition metal tungsten-based sulfides,is scarcely reported in the wide-temperature field.Thus,tungsten sulphide encapsulated in a sulp...Currently,the investigation of two-dimensional(2D)crystalline materials,notably transition metal tungsten-based sulfides,is scarcely reported in the wide-temperature field.Thus,tungsten sulphide encapsulated in a sulphurized polyacrylonitrile composite(WS_(2)-SPAN)was prepared using an electrospinning technology combined with a sulphuration process.By virtue of the abundant S vacancies and in situ N doping,the WS_(2)-SPAN composite shows an impressively ultralong lifespan and stable circulation capacity over a wide temperature range(−15-50℃).For sodium storage,the WS_(2)-SPAN-2 composite delivers optimized high-rate performance and ultrastable cycling properties(464 mA h g^(-1)/450 cycles at 0.5 A g^(-1);354 mA h g^(-1)/1400 cycles at 2 A g^(-1),190 mA h g^(-1)/12000 cycles at 5 A g^(-1);129 mA h g^(-1)/18000 cycles at 10 A g^(-1),surpassing previously reported WS_(2)-based anodes for SIBs).This is paired with an Na_(3)V_(2)(PO_(4))_(3)cathode,which exhibits excellent storage capacity(241 mA h g^(-1)/200 cycles at 0.5 A g^(-1)).Potassium storage also demonstrates admirable performance(362 mA h g^(-1)/100 cycles at 0.1 A g^(-1);278 mA h g^(-1)/3000 cycles at 1 A g^(-1)).In addition,a detailed illustration of the electrochemical storage mechanism of WS_(2)-SPAN composites is presented through theoretical calculations and electrochemical dynamics.Thus,the present investigation provides new insights into the preparation of novel WS_(2)-based anodes for sodium/potassium-ion batteries with ultralong lifespans and wide-temperature workability.展开更多
Rationalizing the use of depleted uranium resources has always been of great interest.Herein,we have obtained two actinide compounds by regulating the ratio of each component in the crystal growth process.By modulatin...Rationalizing the use of depleted uranium resources has always been of great interest.Herein,we have obtained two actinide compounds by regulating the ratio of each component in the crystal growth process.By modulating the coordination microenvironment of uranyl,the actinide compounds exhibited significant differences in photocatalytic CO_(2)reduction performance.The photocatalytic CO_(2)reduction by UCu2 exhibited excellent reactivity,and the CO generation rate reached 481.6μmol g^(−1)h^(−1).This study provides a reference and support for the rational application of depleted uranium resources and the application of coordinated polymers in the field of photocatalytic CO_(2)reduction.展开更多
基金National Natural Science Foundation of China(21878129)the Industry Prospect and Key Core Technology(Competition Project)of Jiangsu Province(BE2019093)Sino-German Cooperation Group Project(GZ1579).
文摘Accelerating light-induced carrier transfer and improving charge utilization are essential for enhancing the efficiency of solar hydrogen production.In this work,for the first time,2D/2D covalent organicframework(COF)/SnNb_(2)O_(6)nanosheets were fabricated by a hydrothermal process.By adjusting the content of TpPa-2-COF,it was used to optimize the performance of solar hydrogen production.The optimal TpPa-2-COF/SnNb_(2)O_(6)nanosheets show a hydrogen production rate of 7.66μmol·h^(−1),which is 5.8-fold and 3.5-fold that of pristine SnNb_(2)O_(6)and TpPa-2-COF,respectively.The significant improvement in the photocatalytic performance can be attributed to the formation of a 2D/2D heterojunction nanosheet with a good energy band position between TpPa-2-COF and SnNb_(2)O_(6),which can efficaciously inhibit the restructuring of charge carriers.Through photoelectrochemical analysis,it is further proved that the interface interaction between TpPa-2-COF and SnNb_(2)O_(6)can lead to effective charge separation.Moreover,the cycling experiments reveal that the as-prepared photocatalyst has excellent stability and recycling performance.This study shows that the smart integration of organic(COF)and inorganic materials into a heterojunction with a 2D/2D structure is an available tactic for the fabrication of efficient photocatalysts.
基金financially supported by the National Key Research and Development Program of China(2019YFC1904500)the National Natural Science Foundation of China(NSFC 51502036 and 21875037)+2 种基金the Department of Ecology and Environment of Fujian Province(2021R024)the Young Top Talent of Fujian Young Eagle Program of Fujian Province,the Educational Commission of Fujian Province(2022G02022)the Natural Science Foundation of Distinguished Young Scholars for Fujian Province(2019J06015).
文摘Currently,the investigation of two-dimensional(2D)crystalline materials,notably transition metal tungsten-based sulfides,is scarcely reported in the wide-temperature field.Thus,tungsten sulphide encapsulated in a sulphurized polyacrylonitrile composite(WS_(2)-SPAN)was prepared using an electrospinning technology combined with a sulphuration process.By virtue of the abundant S vacancies and in situ N doping,the WS_(2)-SPAN composite shows an impressively ultralong lifespan and stable circulation capacity over a wide temperature range(−15-50℃).For sodium storage,the WS_(2)-SPAN-2 composite delivers optimized high-rate performance and ultrastable cycling properties(464 mA h g^(-1)/450 cycles at 0.5 A g^(-1);354 mA h g^(-1)/1400 cycles at 2 A g^(-1),190 mA h g^(-1)/12000 cycles at 5 A g^(-1);129 mA h g^(-1)/18000 cycles at 10 A g^(-1),surpassing previously reported WS_(2)-based anodes for SIBs).This is paired with an Na_(3)V_(2)(PO_(4))_(3)cathode,which exhibits excellent storage capacity(241 mA h g^(-1)/200 cycles at 0.5 A g^(-1)).Potassium storage also demonstrates admirable performance(362 mA h g^(-1)/100 cycles at 0.1 A g^(-1);278 mA h g^(-1)/3000 cycles at 1 A g^(-1)).In addition,a detailed illustration of the electrochemical storage mechanism of WS_(2)-SPAN composites is presented through theoretical calculations and electrochemical dynamics.Thus,the present investigation provides new insights into the preparation of novel WS_(2)-based anodes for sodium/potassium-ion batteries with ultralong lifespans and wide-temperature workability.
基金the National Natural Science Foundation of China(No.22076187,22076186,and 11875138)the National Science Fund for Distinguished Young Scholars(21925603).
文摘Rationalizing the use of depleted uranium resources has always been of great interest.Herein,we have obtained two actinide compounds by regulating the ratio of each component in the crystal growth process.By modulating the coordination microenvironment of uranyl,the actinide compounds exhibited significant differences in photocatalytic CO_(2)reduction performance.The photocatalytic CO_(2)reduction by UCu2 exhibited excellent reactivity,and the CO generation rate reached 481.6μmol g^(−1)h^(−1).This study provides a reference and support for the rational application of depleted uranium resources and the application of coordinated polymers in the field of photocatalytic CO_(2)reduction.
