Perovskite nanocrystals(PNCs)have recently become promising optoelectronic materials due to their excellent photophysical properties.However,the highly dynamic binding state between ligands and the surface of PNCs has...Perovskite nanocrystals(PNCs)have recently become promising optoelectronic materials due to their excellent photophysical properties.However,the highly dynamic binding state between ligands and the surface of PNCs has severely restricted their luminescent properties and stabilities.In this work,1,3-bisbenzyl-2-oxoimidazolidine-4,5-dicarboxylic acid(cycle acid,CA)is introduced as both an etchant and a ligand upon post-synthetic surface treatment of PNCs.By removing the imperfect octahedrons[Pb X_(6)]^(4-)and passivating the surface defects synergistically,this treatment improves photoluminescence quantum yields from 76%to 95%and enhances the stability of PNCs against polar solvent,moisture,heat,and illumination.Meanwhile,CA can effectively and instantly recover the luminescence emission for aged PNCs.As a result,the CA-Cs Pb Br_(3)PNCs and CA-Cs Pb IxBr_(3-x)PNCs are applied as color-converting layers on a blue LED chip for warm white light-emitting diodes(WLEDs)with a color coordinate of(0.41,0.40).Importantly,the CA-based WLED device exhibits superior stability in operational conditions.展开更多
The development of earth-abundant-metal-based electrocatalysts with high efficiency and long-term stability for hydrogen evolution reaction(HER)is crucial for the clean and renewable energy application.Herein,we repor...The development of earth-abundant-metal-based electrocatalysts with high efficiency and long-term stability for hydrogen evolution reaction(HER)is crucial for the clean and renewable energy application.Herein,we report a molten-salt method to synthesize Co-doped CaMn_(3)O_(6)(CMO)nanowires(NWs)as effective electrocatalyst for HER.The as-obtained CaMn_(3-x)Co_(x)O_(6)(CMCO)exhibits a small onset overpotential of 70 mV,a required overpotential of 140 mV at a current density of 10 mA·cm^(-2),a Tafel slope of 39 mV·dec^(-1)in 0.1 M HClO_(4),and a satisfying long-term stability.Experimental characterizations combined with density functional theory(DFT)calculations demonstrate that the obtained HER performance can be attributed to the Co-doping which altered CMO’s surface electronic structures and properties.Considering the simplicity of synthesis route and the abundance of the pertinent elements,the synthesized CMCO shows a promising prospect as a candidate for the development of earth-abundant,metal-based,and cost-effective electrocatalyst with superior HER activity.Our results also establish a strategy of rational design and construction of novel electrocatalyst toward HER by tailoring band structures of transition metal oxides(TMOs).展开更多
基金financial from the National Natural Science Foundation of China(22279039 and 20181194)the Chinese National 1000-Talent-Plan program+2 种基金the Innovation Project of Optics Valley Laboratory(OVL2021BG008)the Frontier of the Application Foundation of Wuhan Science and Technology Plan Project(2020010601012202)the Foundation of State Key Laboratory of New Textile Materials and Advanced Processing Technologies(FZ2021011)。
文摘Perovskite nanocrystals(PNCs)have recently become promising optoelectronic materials due to their excellent photophysical properties.However,the highly dynamic binding state between ligands and the surface of PNCs has severely restricted their luminescent properties and stabilities.In this work,1,3-bisbenzyl-2-oxoimidazolidine-4,5-dicarboxylic acid(cycle acid,CA)is introduced as both an etchant and a ligand upon post-synthetic surface treatment of PNCs.By removing the imperfect octahedrons[Pb X_(6)]^(4-)and passivating the surface defects synergistically,this treatment improves photoluminescence quantum yields from 76%to 95%and enhances the stability of PNCs against polar solvent,moisture,heat,and illumination.Meanwhile,CA can effectively and instantly recover the luminescence emission for aged PNCs.As a result,the CA-Cs Pb Br_(3)PNCs and CA-Cs Pb IxBr_(3-x)PNCs are applied as color-converting layers on a blue LED chip for warm white light-emitting diodes(WLEDs)with a color coordinate of(0.41,0.40).Importantly,the CA-based WLED device exhibits superior stability in operational conditions.
基金supported by the Ministry of Science and Technology of China(2021YFA1200501)the National Natural Science Foundation of China(U22A20137,U21A2069,and 21825103)+2 种基金Guangdong Basic and Applied Basic Research Foundation(2020A1515110330)Shenzhen Science and Technology Innovation Program(JCYJ20220818102215033,GJHZ20210705142542015,and JCYJ20220530160811027)the support from the Queen Mary–HUST Strategic Partner Fund。
基金This work was financially supported by the National Key Research and Development Program of China(No.2020YFB2008502)the National Natural Science Foundation of China(Nos.51972124,51872101,51902115,and 12172143)the Innovation Fund of Wuhan National Laboratory for Optoelectronics(WNLO)。
文摘The development of earth-abundant-metal-based electrocatalysts with high efficiency and long-term stability for hydrogen evolution reaction(HER)is crucial for the clean and renewable energy application.Herein,we report a molten-salt method to synthesize Co-doped CaMn_(3)O_(6)(CMO)nanowires(NWs)as effective electrocatalyst for HER.The as-obtained CaMn_(3-x)Co_(x)O_(6)(CMCO)exhibits a small onset overpotential of 70 mV,a required overpotential of 140 mV at a current density of 10 mA·cm^(-2),a Tafel slope of 39 mV·dec^(-1)in 0.1 M HClO_(4),and a satisfying long-term stability.Experimental characterizations combined with density functional theory(DFT)calculations demonstrate that the obtained HER performance can be attributed to the Co-doping which altered CMO’s surface electronic structures and properties.Considering the simplicity of synthesis route and the abundance of the pertinent elements,the synthesized CMCO shows a promising prospect as a candidate for the development of earth-abundant,metal-based,and cost-effective electrocatalyst with superior HER activity.Our results also establish a strategy of rational design and construction of novel electrocatalyst toward HER by tailoring band structures of transition metal oxides(TMOs).
