Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials ...Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability.展开更多
Modifying electrocatalysts nanostructures and tuning their electronic properties through defects-oriented synthetic strategies are:essential to improve the oxygen evolution reaction(OER)performance of electrocatalysts...Modifying electrocatalysts nanostructures and tuning their electronic properties through defects-oriented synthetic strategies are:essential to improve the oxygen evolution reaction(OER)performance of electrocatalysts.Current synthetic strategies about.electrocatalysts mainly target the single or double structural defects,while the researches about the synergistic effect of multiple'structural defects are rare.In this work,the ultrathin NiFe layered double hydroxide nanosheets with a holey structure,oxygen;vacancies and Ni^(3+)defects on nickel foam(NiFe-LDH-NSs/NF)are prepared by employing a simple and green H202-assisted etching 1 method.The synergistic effect ofthe above three defects leads to the exposure of.more active sites and significant improvement of:the intrinsic activity.The optimized catalyst exhibits an excellent OER performance with an extraordinarily low overpotential of 170 mV;at to mA·cm^(-2) and a small Tafel slope of 39.3 mV·dec^(-1) in 1 M KOH solution.Density functional theory calculations reveal this OER;performance arises from pseudo re-oxidized metal-stable Ni^(3+)near oxygen vacancies(O_(vac)),which suppresses 3d-e_(g) of Ni-site and!elevates d-band center towards the competitively low electron-transferbarrier.This work provides a new insight to fabricate advanced electrocatalysts for renewable energy conversion technologies.展开更多
Using simple methods to obtain efficient catalysts has been a long-standing goal for researchers.In this work,the employment of a one-pot pyrolysis reaction to achieve molecular confinement,has led to the preparation ...Using simple methods to obtain efficient catalysts has been a long-standing goal for researchers.In this work,the employment of a one-pot pyrolysis reaction to achieve molecular confinement,has led to the preparation of ruthenium(Ru)-based nanoclusters in a carbon matrix.A unique feature of the synthetic approach employed is that solvent and substrates were calcined together.As solvent evaporates,during calcination,the substrates form a dense solid which has the effect of limiting the aggregation of Ru centers during the carbonization process.The catalyst prepared in this simple manner showed an impressively high activity with respect to the hydrogen/oxygen evolution reaction(HER/OER).The Ru nanoclusters(Ru NCs),as the hydrogen evolution reaction(HER)catalysts,require ultralow overpotentials of 5 mV and 5.1 mV at-10 mA·cm^(-2) in 1.0 M KOH,and 0.5 M H_(2)SO_(4),respectively.Furthermore,the catalyst prepared by the one-pot method has higher crystallinity,a higher Ru content and an ultrafine cluster size,which contributes to its exceptional electrochemical performance.Meanwhile,the RuO_(x) nanoclusters(RuO_(x) NCs),obtained by oxidizing the aforementioned Ru NCs,exhibited good oxygen evolution reaction(OER)performance with an overpotential of 266 mV at 10 mA·cm^(-2).When applied to overall water splitting,Ru/RuO_(x) nanoclusters as the cathode and anode catalysts can reach 10 mA·cm^(-2) at cell voltages of only 1.49 V in 1 M KOH.展开更多
基金financially supported by the National Key R&D Program of China(Grant No.2022YFE0207300)National Natural Science Foundation of China(Grant Nos.22179142 and 22075314)+1 种基金Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2024ZB051 and 2023ZB836)the technical support for Nano-X from Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences(SINANO).
文摘Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability.
基金supports from the National Natural Science Foundation of China(Nos.21531006 and 21773163)the State Key Laboratory of Organometallic Chemistry of Shanghai Institute of Organic Chemistry(No.KF2021005)Collaborative Innovation Center of Suzhou Nano Science and Technology,the“Priority Academic Program Development”of Jiangsu Higher Education Institutions,and the Project of Scientific and Technologic Infrastructure of Suzhou(No.SZS201905).
文摘Modifying electrocatalysts nanostructures and tuning their electronic properties through defects-oriented synthetic strategies are:essential to improve the oxygen evolution reaction(OER)performance of electrocatalysts.Current synthetic strategies about.electrocatalysts mainly target the single or double structural defects,while the researches about the synergistic effect of multiple'structural defects are rare.In this work,the ultrathin NiFe layered double hydroxide nanosheets with a holey structure,oxygen;vacancies and Ni^(3+)defects on nickel foam(NiFe-LDH-NSs/NF)are prepared by employing a simple and green H202-assisted etching 1 method.The synergistic effect ofthe above three defects leads to the exposure of.more active sites and significant improvement of:the intrinsic activity.The optimized catalyst exhibits an excellent OER performance with an extraordinarily low overpotential of 170 mV;at to mA·cm^(-2) and a small Tafel slope of 39.3 mV·dec^(-1) in 1 M KOH solution.Density functional theory calculations reveal this OER;performance arises from pseudo re-oxidized metal-stable Ni^(3+)near oxygen vacancies(O_(vac)),which suppresses 3d-e_(g) of Ni-site and!elevates d-band center towards the competitively low electron-transferbarrier.This work provides a new insight to fabricate advanced electrocatalysts for renewable energy conversion technologies.
基金support from the National Natural Science Foundation of China(Nos.21531006 and 21773163)Collaborative Innovation Center of Suzhou Nano Science and Technology,the Priority Academic Program Development of Jiangsu Higher Education Institutions,the Project of Scientific and Technologic Infrastructure of Suzhou(No.SZS201905)the Research Fund Program of Key Laboratory of Rare Mineral,MNR(No.KLRM-KF202004).
文摘Using simple methods to obtain efficient catalysts has been a long-standing goal for researchers.In this work,the employment of a one-pot pyrolysis reaction to achieve molecular confinement,has led to the preparation of ruthenium(Ru)-based nanoclusters in a carbon matrix.A unique feature of the synthetic approach employed is that solvent and substrates were calcined together.As solvent evaporates,during calcination,the substrates form a dense solid which has the effect of limiting the aggregation of Ru centers during the carbonization process.The catalyst prepared in this simple manner showed an impressively high activity with respect to the hydrogen/oxygen evolution reaction(HER/OER).The Ru nanoclusters(Ru NCs),as the hydrogen evolution reaction(HER)catalysts,require ultralow overpotentials of 5 mV and 5.1 mV at-10 mA·cm^(-2) in 1.0 M KOH,and 0.5 M H_(2)SO_(4),respectively.Furthermore,the catalyst prepared by the one-pot method has higher crystallinity,a higher Ru content and an ultrafine cluster size,which contributes to its exceptional electrochemical performance.Meanwhile,the RuO_(x) nanoclusters(RuO_(x) NCs),obtained by oxidizing the aforementioned Ru NCs,exhibited good oxygen evolution reaction(OER)performance with an overpotential of 266 mV at 10 mA·cm^(-2).When applied to overall water splitting,Ru/RuO_(x) nanoclusters as the cathode and anode catalysts can reach 10 mA·cm^(-2) at cell voltages of only 1.49 V in 1 M KOH.
