Li-S batteries have attracted considerable interest as nextgeneration energy storage devices owing to high energy density and the natural abundance of sulfur.However,the practical applications of Li-S batteries are ha...Li-S batteries have attracted considerable interest as nextgeneration energy storage devices owing to high energy density and the natural abundance of sulfur.However,the practical applications of Li-S batteries are hampered by the shuttle effect of soluble lithium polysulfides(LPS),which results in low cycle stability.Herein,a functional interlayer has been developed to efficiently regulate the LPS and enhance the sulfur utilization using hierarchical nanostructure of C3 N4(t-C3 N4)embedded with Fe304 nanospheres.t-C3 N4 exhibits high surface area and strong anchoring of LPS,and the Fe3 O4/t-C3 N4 accelerates the anchoring of LPS and improves the electronic pathways.The combination of these materials leads to remarkable battery performance with 400%improvement in a specific capacity and a low capacity decay per cycle of 0.02%at 2 C over 1000 cycles,and stable cycling at 6.4 mg cm-2 for high-sulfur-loading cathode.展开更多
Novel WO3/g-C3N4/Ni(OH)x hybrids have been successfully synthesized by a two-step strategy of high temperature calcination and in situ photodeposition.Their photocatalytic performance was investigated using TEOA as ...Novel WO3/g-C3N4/Ni(OH)x hybrids have been successfully synthesized by a two-step strategy of high temperature calcination and in situ photodeposition.Their photocatalytic performance was investigated using TEOA as a hole scavenger under visible light irradiation.The loading of WO3 and Ni(OH)x cocatalysts boosted the photocatalytic H2 evolution efficiency of g-C3N4.WO3/g-C3N4/Ni(OH)x with 20 wt%defective WO3 and 4.8 wt%Ni(OH)x showed the highest hydrogen production rate of 576 μmol/(g·h),which was 5.7,10.8 and 230 times higher than those of g-C3N4/4.8 wt%Ni(OH)x,20 wt%WO3/C3N4 and g-C3N4 photocatalysts,respectively.The remarkably enhanced H2 evolution performance was ascribed to the combination effects of the Z-scheme heterojunction(WO3/g-C3N4) and loaded cocatalysts(Ni(OH)x),which effectively inhibited the recombination of the photoexcited electron-hole pairs of g-C3N4 and improved both H2 evolution and TEOA oxidation kinetics.The electron spin resonance spectra of ·O2^- and ·OH radicals provided evidence for the Z-scheme charge separation mechanism.The loading of easily available Ni(OH)x cocatalysts on the Z-scheme WO3/g-C3N4 nanocomposites provided insights into constructing a robust multiple-heterojunction material for photocatalytic applications.展开更多
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(NRF-2019R1A2C1003594 and NRF-2019R1A2C1003551)。
文摘Li-S batteries have attracted considerable interest as nextgeneration energy storage devices owing to high energy density and the natural abundance of sulfur.However,the practical applications of Li-S batteries are hampered by the shuttle effect of soluble lithium polysulfides(LPS),which results in low cycle stability.Herein,a functional interlayer has been developed to efficiently regulate the LPS and enhance the sulfur utilization using hierarchical nanostructure of C3 N4(t-C3 N4)embedded with Fe304 nanospheres.t-C3 N4 exhibits high surface area and strong anchoring of LPS,and the Fe3 O4/t-C3 N4 accelerates the anchoring of LPS and improves the electronic pathways.The combination of these materials leads to remarkable battery performance with 400%improvement in a specific capacity and a low capacity decay per cycle of 0.02%at 2 C over 1000 cycles,and stable cycling at 6.4 mg cm-2 for high-sulfur-loading cathode.
基金supported by the National Natural Science Foundation of China (51672089)the Industry and Research Collaborative Innovation Major Projects of Guangzhou (201508020098)+1 种基金the State Key Laboratory of Advanced Technology for Material Synthesis and Processing (Wuhan University of Technology) (2015-KF-7)the Hunan Key Laboratory of Applied Environmental Photocatalysis (Changsha University) (CCSU-XT-04)~~
文摘Novel WO3/g-C3N4/Ni(OH)x hybrids have been successfully synthesized by a two-step strategy of high temperature calcination and in situ photodeposition.Their photocatalytic performance was investigated using TEOA as a hole scavenger under visible light irradiation.The loading of WO3 and Ni(OH)x cocatalysts boosted the photocatalytic H2 evolution efficiency of g-C3N4.WO3/g-C3N4/Ni(OH)x with 20 wt%defective WO3 and 4.8 wt%Ni(OH)x showed the highest hydrogen production rate of 576 μmol/(g·h),which was 5.7,10.8 and 230 times higher than those of g-C3N4/4.8 wt%Ni(OH)x,20 wt%WO3/C3N4 and g-C3N4 photocatalysts,respectively.The remarkably enhanced H2 evolution performance was ascribed to the combination effects of the Z-scheme heterojunction(WO3/g-C3N4) and loaded cocatalysts(Ni(OH)x),which effectively inhibited the recombination of the photoexcited electron-hole pairs of g-C3N4 and improved both H2 evolution and TEOA oxidation kinetics.The electron spin resonance spectra of ·O2^- and ·OH radicals provided evidence for the Z-scheme charge separation mechanism.The loading of easily available Ni(OH)x cocatalysts on the Z-scheme WO3/g-C3N4 nanocomposites provided insights into constructing a robust multiple-heterojunction material for photocatalytic applications.