Lithium-sulfur batteries(LSBs) hold great potential for large-scale electrochemical energy storage applications. Currently, the shuttle of soluble lithium polysulfide(LiPSs) intermediates with sluggish conversion kine...Lithium-sulfur batteries(LSBs) hold great potential for large-scale electrochemical energy storage applications. Currently, the shuttle of soluble lithium polysulfide(LiPSs) intermediates with sluggish conversion kinetics and random deposition of Li2S have severely degraded the capacity, rate and cycling performances of LSBs, preventing their practical applications. In this work, ultrathin MoSe2 nanosheets with active edge sites were successfully grown on both internal and external surfaces of hollow carbon spheres with mesoporous walls(MCHS). The resulting MoSe2@MCHS composite acted as a novel functional reservoir for Li PSs with high chemical affinity and effectively mediated their fast redox conversion during charge/discharge as elucidated by experimental observations and first-principles density functional theory(DFT) calculations. The as-fabricated Li-S cells delivered high capacity, superior rate and excellent cyclability. The current work presents new insights on the delicate design and fabrication of novel functional composite electrode materials for rechargeable batteries with emerging applications.展开更多
Oil pollution is causing deleterious damage to aquatic ecosystems and human health.The utilization of agricultural waste such as corn stalk(CS)to produce biosorbents has been considered an ecofriendly and efficient ap...Oil pollution is causing deleterious damage to aquatic ecosystems and human health.The utilization of agricultural waste such as corn stalk(CS)to produce biosorbents has been considered an ecofriendly and efficient approach for removing oil.However,most previous studies focused on the modification of the whole CS,which is inefficient due to the heterogeneity of CS.In this study,corn stalk pith(CP),which has excellent amphipathic characteristics,was selected to prepare a high-efficiency oil sorbent by grafting dodecyl gallate(DG,a long-chain alkyl)onto CP surface lignin via laccase mediation.The modified biomass(DGCP)shows high hydrophobicity(water contact angle=140.2°)and superoleophilicity(oil contact angle=0°)and exhibits a high oil sorption capacity(46.43 g/g).In addition,DGCP has good stability and reusability for adsorbing oil from the aqueous phase.Kinetic and isotherm models and two-dimensional correlation spectroscopy integrated with FTIR analyses revealed that the main sorption mechanism involves the H-bond effect,hydrophobic effect and van der Waals force.This work provides an ecofriendly method to prepare oil sorbents and new insights into the mechanisms underlying the removal of spilled oil from wastewater.展开更多
基金financially supported by the National Natural Science Foundation of China (51302204, 21902122)Postdoctoral Science Foundation of China (2019M652723)+2 种基金Hunan Provincial Science and Technology Plan Project (No.2017TP1001)Program for Changjiang Scholars and Innovative Research Team in University (IRT_15R52)Hubei Provincial Department of Education for the “Chutian Scholar” program。
文摘Lithium-sulfur batteries(LSBs) hold great potential for large-scale electrochemical energy storage applications. Currently, the shuttle of soluble lithium polysulfide(LiPSs) intermediates with sluggish conversion kinetics and random deposition of Li2S have severely degraded the capacity, rate and cycling performances of LSBs, preventing their practical applications. In this work, ultrathin MoSe2 nanosheets with active edge sites were successfully grown on both internal and external surfaces of hollow carbon spheres with mesoporous walls(MCHS). The resulting MoSe2@MCHS composite acted as a novel functional reservoir for Li PSs with high chemical affinity and effectively mediated their fast redox conversion during charge/discharge as elucidated by experimental observations and first-principles density functional theory(DFT) calculations. The as-fabricated Li-S cells delivered high capacity, superior rate and excellent cyclability. The current work presents new insights on the delicate design and fabrication of novel functional composite electrode materials for rechargeable batteries with emerging applications.
基金supported by the National Natural Science Foundation of China(Nos. 42007323, 42007107)the Natural Science Foundation of Guangdong Province, China(No. 2018A030313363)+2 种基金the Open Fund of the Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control, China(No. 2018B030322017)the High-level Professionals and Innovative Teams, Shenzhen, China(Nos. SZIIT2019KJ024,SZIIT2019KJ007)the Shenzhen Science & Technology Project, China(No. SZIITWDZC2021A01)
文摘Oil pollution is causing deleterious damage to aquatic ecosystems and human health.The utilization of agricultural waste such as corn stalk(CS)to produce biosorbents has been considered an ecofriendly and efficient approach for removing oil.However,most previous studies focused on the modification of the whole CS,which is inefficient due to the heterogeneity of CS.In this study,corn stalk pith(CP),which has excellent amphipathic characteristics,was selected to prepare a high-efficiency oil sorbent by grafting dodecyl gallate(DG,a long-chain alkyl)onto CP surface lignin via laccase mediation.The modified biomass(DGCP)shows high hydrophobicity(water contact angle=140.2°)and superoleophilicity(oil contact angle=0°)and exhibits a high oil sorption capacity(46.43 g/g).In addition,DGCP has good stability and reusability for adsorbing oil from the aqueous phase.Kinetic and isotherm models and two-dimensional correlation spectroscopy integrated with FTIR analyses revealed that the main sorption mechanism involves the H-bond effect,hydrophobic effect and van der Waals force.This work provides an ecofriendly method to prepare oil sorbents and new insights into the mechanisms underlying the removal of spilled oil from wastewater.
