Seawater splitting into hydrogen,a promising technology,is seriously limited by the durability and tolerance of electrocatalysts for chlorine ions in seawater at large current densities due to chloride oxidation and c...Seawater splitting into hydrogen,a promising technology,is seriously limited by the durability and tolerance of electrocatalysts for chlorine ions in seawater at large current densities due to chloride oxidation and corrosion.Here,we present a robust and weak-nucleophilicity nickel-iron hydroxide electrocatalyst with excellent selectivity for oxygen evolution and an inert response for chlorine ion oxidation which are key and highly desired for efficient seawater electrolysis.Such a weak-nucleophilicity electrocatalyst can well match with strong-nucleophilicity OH-compared with the weak-nucleophilicity Cl^(-),resultantly,the oxidation of OH-in electrolyte can be more easily achieved relative to chlorine ion oxidation,confirmed by ethylenediaminetetraacetic acid disodium probing test.Further,no strongly corrosive hypochlorite is produced when the operating voltage reaches about 2.1 V vs.RHE,a potential that is far beyond the thermodynamic potential of chlorine ion oxidatio n.This concept and approach to reasonably designing weaknucleophilicity electrocatalysts that can greatly avoid chlorine ion oxidation under alkaline seawater environments can push forward the seawater electrolysis technology and also accelerate the development of green hydrogen technique.展开更多
The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and...The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and SOT-C with three-dimensional network structure containing polar groups(sulfhydryl groups,amide groups and amino groups)are synthesized by the nucleophilic ring-opening polymerization(ROP)of thiolactone with amino groups.The network structure formed by hydrogen bonds and functional groups can resist the volume change of the cathode.The sulfhydryl groups and the S-S bond formed by oxidative dehydrogenation of sulfhydryl group participate in the charge and discharge process of the battery as active materials,which improves the discharge specific capacity of the battery.Polar functional groups have strong chemisorption on polysulfides and effectively inhibit the“shuttle effect”.The electrochemical performances of Li-S batteries containing SOT-A and SOT-C binders are significantly enhanced.At 1 C rate,the batteries achieve initial discharge specific capacity of 871 and 837 mAh·g^(-1),respectively,and have 83.9%and 62.5%capacity retention after 500 cycles.展开更多
We present a ring-opening polymerization of bridged cyclic lactone utilizing alcohol as the initiator and organic base as the catalyst.Bridged γ-butyrolactone monomers(PhSGBL and PhSeGBL)were synthesized efficiently ...We present a ring-opening polymerization of bridged cyclic lactone utilizing alcohol as the initiator and organic base as the catalyst.Bridged γ-butyrolactone monomers(PhSGBL and PhSeGBL)were synthesized efficiently from commercially available 3-cyclohexene-1-carboxylic acid.Due to the ring strain of the bridged structure,ring-opening polymerization of this type of γ-butyrolactone derivative was successfully carried out under mild conditions,e.g.,using ethylene glycol as the initiator and a commercial catalyst[1,5,7-triazabicyclo[4.4.0 dec-5-ene(TBD)]]as the catalyst at 30℃.The obtained polymer could be degraded to its monomer for recycling in the presence of ZnCl_(2) as a catalyst.PhSGBL and PhSeGBL could also be copolymerized with ε-caprolactone to tune the glass transition temperature.Additionally,the hydrophilicity of the obtained sulfur-containing polymers could be adjusted by selectively oxidizing the thioether side group to sulfone/sulfoxide,which offered a way to tune the hydrophilicity of polyester.On the other hand,the obtained selenium-containing compound could be degraded in the presence of m-CPBA(3-chloroperbenzoic acid),which offered potential application in sustained drug release.展开更多
基金supported by the National Natural Science Foundation of China(NSFC,No.22078052)the Fundamental Research Funds for the Central Universities(DUT22ZD207,DUT22LAB612)。
文摘Seawater splitting into hydrogen,a promising technology,is seriously limited by the durability and tolerance of electrocatalysts for chlorine ions in seawater at large current densities due to chloride oxidation and corrosion.Here,we present a robust and weak-nucleophilicity nickel-iron hydroxide electrocatalyst with excellent selectivity for oxygen evolution and an inert response for chlorine ion oxidation which are key and highly desired for efficient seawater electrolysis.Such a weak-nucleophilicity electrocatalyst can well match with strong-nucleophilicity OH-compared with the weak-nucleophilicity Cl^(-),resultantly,the oxidation of OH-in electrolyte can be more easily achieved relative to chlorine ion oxidation,confirmed by ethylenediaminetetraacetic acid disodium probing test.Further,no strongly corrosive hypochlorite is produced when the operating voltage reaches about 2.1 V vs.RHE,a potential that is far beyond the thermodynamic potential of chlorine ion oxidatio n.This concept and approach to reasonably designing weaknucleophilicity electrocatalysts that can greatly avoid chlorine ion oxidation under alkaline seawater environments can push forward the seawater electrolysis technology and also accelerate the development of green hydrogen technique.
基金This work was supported by the National Natural Science Foundation of China(Project No.U20A20260)the China Central Government Guide for the Development of Local Science and Technology Special Funds(226Z1202G)the Natural Science Foundation of Hebei Province(Grant Nos.B2020202042,B2020202073 and C20200320).
文摘The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and SOT-C with three-dimensional network structure containing polar groups(sulfhydryl groups,amide groups and amino groups)are synthesized by the nucleophilic ring-opening polymerization(ROP)of thiolactone with amino groups.The network structure formed by hydrogen bonds and functional groups can resist the volume change of the cathode.The sulfhydryl groups and the S-S bond formed by oxidative dehydrogenation of sulfhydryl group participate in the charge and discharge process of the battery as active materials,which improves the discharge specific capacity of the battery.Polar functional groups have strong chemisorption on polysulfides and effectively inhibit the“shuttle effect”.The electrochemical performances of Li-S batteries containing SOT-A and SOT-C binders are significantly enhanced.At 1 C rate,the batteries achieve initial discharge specific capacity of 871 and 837 mAh·g^(-1),respectively,and have 83.9%and 62.5%capacity retention after 500 cycles.
基金financially supported by National Key Research and Development Program of China(No.2022YFB3704905)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘We present a ring-opening polymerization of bridged cyclic lactone utilizing alcohol as the initiator and organic base as the catalyst.Bridged γ-butyrolactone monomers(PhSGBL and PhSeGBL)were synthesized efficiently from commercially available 3-cyclohexene-1-carboxylic acid.Due to the ring strain of the bridged structure,ring-opening polymerization of this type of γ-butyrolactone derivative was successfully carried out under mild conditions,e.g.,using ethylene glycol as the initiator and a commercial catalyst[1,5,7-triazabicyclo[4.4.0 dec-5-ene(TBD)]]as the catalyst at 30℃.The obtained polymer could be degraded to its monomer for recycling in the presence of ZnCl_(2) as a catalyst.PhSGBL and PhSeGBL could also be copolymerized with ε-caprolactone to tune the glass transition temperature.Additionally,the hydrophilicity of the obtained sulfur-containing polymers could be adjusted by selectively oxidizing the thioether side group to sulfone/sulfoxide,which offered a way to tune the hydrophilicity of polyester.On the other hand,the obtained selenium-containing compound could be degraded in the presence of m-CPBA(3-chloroperbenzoic acid),which offered potential application in sustained drug release.
