氢能作为一种潜在的能源载体,有望取代化石燃料,解决当今社会的能源需求和环境问题.质子交换膜电解水(PEMWE)技术因其工作电流密度大、氢气纯度高和系统响应迅速等优点,能够有效地弥补可再生能源波动性等缺点,被认为是一种利用可再生能...氢能作为一种潜在的能源载体,有望取代化石燃料,解决当今社会的能源需求和环境问题.质子交换膜电解水(PEMWE)技术因其工作电流密度大、氢气纯度高和系统响应迅速等优点,能够有效地弥补可再生能源波动性等缺点,被认为是一种利用可再生能源制氢的可持续手段.但其阳极氧析出反应(OER)为四电子/质子转移过程,反应动力学缓慢,同时强氧化性和强酸性环境会对阳极催化剂的产生腐蚀,导致稳定性差,因此亟需开发高效且稳定的催化剂.研究发现,无定型氧化铱材料中的特殊缺陷结构可显著提升其催化酸性OER的活性,但该结构也会加速反应过程中铱的溶解,导致催化剂稳定性降低,严重限制了其实际应用.本文采用高价金属掺杂的策略,利用高价金属元素与氧的强成键作用,对无定型氧化铱的整体结构及活性位点起到优化且稳定的作用.首先,采用改性的亚当斯熔融法制备了金属钽掺杂的无定型氧化铱:350-Ta@IrO_(x),400-Ta@IrO_(x),450-Ta@IrO_(x)(350,400和450代表样品分别在350,400和450℃烧结),并用于催化酸性OER;作为对比,制备了无掺杂的无定型氧化铱:350-IrO_(x),400-IrO_(x)和450-IrO_(x).然后,通过扫描电子显微镜、透射电子显微镜(TEM)和X射线衍射等表征技术考察了材料的宏观形貌及微观结构.结果表明,掺杂后的350-Ta@IrO_(x)材料表面具有丰富的氧空位贡献的活性位点,且表现出多晶的超小纳米颗粒形貌.电化学测试结果表明,350-Ta@IrO_(x)具有较好的酸性OER活性,在10 mA cm-2的电流密度下,过电势仅为223 mV,在1.55 V vs.RHE的电位下质量活性为1207.4 A gIr-1,是商业二氧化铱的147.7倍.且该催化剂的稳定性比未掺杂Ta样品及商业二氧化铱有明显提升,在0.5 mol L^(-1)硫酸溶液中反应500 h后电位未发生明显变化.密度泛函理论计算结果表明,Ta掺杂与构建缺陷有利于OER决速步中水分子的亲核进攻,从而提升催化活性并降低反应过电势.为进一步研究材料在酸性OER工作状态下具有较好稳定性的原因,采用TEM和X射线光电子能谱等对反应前后的材料进行表征.结果表明,350-Ta@IrO_(x)在反应前后结构保持稳定,Ir溶解速率较未掺杂样品明显降低,证明了Ta掺杂大大提升了无定型氧化铱材料的稳定性.综上,本文发展了制备高价金属掺杂氧化铱的改性亚当斯熔融法,利用高价金属元素与氧的强成键作用,调控了铱活性位点的电子结构,同时提升了氧化铱类材料在酸性氧析出反应中的活性与稳定性,简化了此类材料的合成方式,为进一步降低质子交换膜电解水器件阳极催化剂的成本和提高其催化活性提供了新思路.展开更多
Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,li...Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,limiting the accessibility of the repetitive sequences,the centromeric and telomeric regions,and the study of inheritance of important agronomic traits in these regions.Here,we assembled a telomere-to-telomere(T2T)gap-free reference genome for the cultivar PN40024 using PacBio HiFi long reads.The T2T reference genome(PN_T2T)is 69 Mb longer with 9018 more genes identified than the 12X.v0 version.We annotated 67%repetitive sequences,19 centromeres and 36 telomeres,and incorporated gene annotations of previous versions into the PN_T2T assembly.We detected a total of 377 gene clusters,which showed associations with complex traits,such as aroma and disease resistance.Even though PN40024 derives from nine generations of selfing,we still found nine genomic hotspots of heterozygous sites associated with biological processes,such as the oxidation–reduction process and protein phosphorylation.The fully annotated complete reference genome therefore constitutes an important resource for grapevine genetic studies and breeding programs.展开更多
Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotentia...Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotential and high current density.However,its precise synthesis and the understanding of synergisti-cally catalytic effects remain challenging.Herein,we report a facile method to synthesize the bimetallic Cu and Ni clusters anchored on porous carbon(Cu/Ni-NC)and achieve an enhanced ECO_(2)R.The aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy were employed to verify the metal dispersion and the coordination of Cu/Ni clusters on NC.As a result of this route,the target Cu/Ni-NC exhibits excellent electrocatalytic performance including a stable 30 h electrolysis at 200 mA cm^(-2) with carbon monoxide Faradaic efficiency of∼95.1%using a membrane electrode assembly electrolysis cell.Combined with the in situ analysis of the surface-enhanced Fourier transform infrared spectroelectrochemistry,we propose that the synergistic effects between Ni and Cu can effectively promote the H_(2)O dissociation,thereby accelerate the hydrogenation of CO_(2)to*COOH and the overall reaction process.展开更多
Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe an...Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe and N doping porous carb on n ematosphere(FeNPCN)as an excellent CO2RR electrocatalyst in aqueous electrolyte.Featuring with the high conductivity,pore structure and abundant Fe and N doping,FeNPCN exhibits high catalytic activity with a high faradaic selectivity of CO(94%)and long-term durability.Moreover,the ratio of CO and H2 can be changed by the applied potential for the different syngas related industry.Density functional theory(DFT)calculation results also reveal that the excellent catalytic activity is likely attributed to C and N hybrid coordination with atomic Fe.展开更多
Efficient oxygen electrocatalysts are the key elements of numerous energy storage and conversion devices, including fuel cells and metal-air batteries. In order to realize their practical applications, highly efficien...Efficient oxygen electrocatalysts are the key elements of numerous energy storage and conversion devices, including fuel cells and metal-air batteries. In order to realize their practical applications, highly efficient and inexpensive non-noble metal-based oxygen electrocatalysts are urgently required. Herein, we report a novel iron-chelated urea-formaldehyde resin hydrogel for the synthesis of Fe-N-C electrocatalysts. This novel hydrogel is prepared using a new instantaneous (20 s) one-step scalable strategy, which theoretically ensures the atomic-level dispersion of Fe ions in the urea-formaldehyde resin, guaranteeing the microstructural homogeneity of the electrocatalyst. Consequentl~ the prepared electrocatalyst exhibits higher catalytic activity and durability in the oxygen reduction (ORR) and evolution (OER) reactions than the commercial Pt/C catalyst. Furthermore, the above catalyst also shows a much better performance in rechargeable Zn-air batteries, including higher power density and better cycling stability. The developed synthetic approach opens up new avenues toward the development of sustainable active electrocatalysts for electrochemical energy devices.展开更多
The development of an electrocatalyst based on abundant elements for the oxygen evolution reaction (OER) is important for water splitting associated with renewable energy sources. In this study, we develop an interc...The development of an electrocatalyst based on abundant elements for the oxygen evolution reaction (OER) is important for water splitting associated with renewable energy sources. In this study, we develop an interconnected Ni(Fe)OxHy nanosheet array on a stainless steel mesh (SSNNi) as an integrated OER electrode, without using any polymer binder. Benefiting from the well- defined three-dimensional (3D) architecture with highly exposed surface area, intimate contact between the active species and conductive substrate improved electron and mass transport capacity, facilitated electrolyte penetration, and improved mechanical stability. The SSNNi electrode also has excellent OER performance, including low overpotential, a small Tafel slope, and long-term durability in the alkaline electrolyte, making it one of the most promising OER electrodes developed.展开更多
Electrochemical CO_(2) reduction reaction(CO_(2)RR)into value-added chemicals/fuels is crucial for realizing the sustainable carbon cycle while mitigating the energy crisis.However,it is impeded by the relatively high...Electrochemical CO_(2) reduction reaction(CO_(2)RR)into value-added chemicals/fuels is crucial for realizing the sustainable carbon cycle while mitigating the energy crisis.However,it is impeded by the relatively high overpotential and low energy efficiency due to the lack of efficient electrocatalysts.Herein,we develop an isolated single-atom Ni catalyst regulated strategy to activate and stabilize the iron phthalocyanine molecule(Ni SA@FePc)toward a highly efficient CO_(2)RR process at low overpotential.The well-defined and homogenous catalytic centers with unique structures confer Ni SA@FePc with a significantly enhanced CO_(2)RR performance compared to single-atom Ni catalyst and FePc molecule and afford the atomic understanding on active sites and catalytic mechanism.As expected,Ni SA@FePc exhibits a high selectivity of more significant Faraday efficiency(≥95%)over a wide potential range,a high current density of~252 mA·cm^(−2) at low overpotential(390 mV),and excellent long-term stability for CO_(2)RR to CO.X-ray absorption spectroscopy measurement and theoretical calculation indicate the formation of NiN_(4)-O_(2)-FePc heterogeneous structure for Ni SA@FePc.And CO_(2)RR prefers to occur at the raised N centers of NiN4-O_(2)-FePc heterogeneous structure for Ni SA@FePc,which enables facilitated adsorption of*COOH and desorption of CO,and thus accelerated overall reaction kinetics.展开更多
文摘氢能作为一种潜在的能源载体,有望取代化石燃料,解决当今社会的能源需求和环境问题.质子交换膜电解水(PEMWE)技术因其工作电流密度大、氢气纯度高和系统响应迅速等优点,能够有效地弥补可再生能源波动性等缺点,被认为是一种利用可再生能源制氢的可持续手段.但其阳极氧析出反应(OER)为四电子/质子转移过程,反应动力学缓慢,同时强氧化性和强酸性环境会对阳极催化剂的产生腐蚀,导致稳定性差,因此亟需开发高效且稳定的催化剂.研究发现,无定型氧化铱材料中的特殊缺陷结构可显著提升其催化酸性OER的活性,但该结构也会加速反应过程中铱的溶解,导致催化剂稳定性降低,严重限制了其实际应用.本文采用高价金属掺杂的策略,利用高价金属元素与氧的强成键作用,对无定型氧化铱的整体结构及活性位点起到优化且稳定的作用.首先,采用改性的亚当斯熔融法制备了金属钽掺杂的无定型氧化铱:350-Ta@IrO_(x),400-Ta@IrO_(x),450-Ta@IrO_(x)(350,400和450代表样品分别在350,400和450℃烧结),并用于催化酸性OER;作为对比,制备了无掺杂的无定型氧化铱:350-IrO_(x),400-IrO_(x)和450-IrO_(x).然后,通过扫描电子显微镜、透射电子显微镜(TEM)和X射线衍射等表征技术考察了材料的宏观形貌及微观结构.结果表明,掺杂后的350-Ta@IrO_(x)材料表面具有丰富的氧空位贡献的活性位点,且表现出多晶的超小纳米颗粒形貌.电化学测试结果表明,350-Ta@IrO_(x)具有较好的酸性OER活性,在10 mA cm-2的电流密度下,过电势仅为223 mV,在1.55 V vs.RHE的电位下质量活性为1207.4 A gIr-1,是商业二氧化铱的147.7倍.且该催化剂的稳定性比未掺杂Ta样品及商业二氧化铱有明显提升,在0.5 mol L^(-1)硫酸溶液中反应500 h后电位未发生明显变化.密度泛函理论计算结果表明,Ta掺杂与构建缺陷有利于OER决速步中水分子的亲核进攻,从而提升催化活性并降低反应过电势.为进一步研究材料在酸性OER工作状态下具有较好稳定性的原因,采用TEM和X射线光电子能谱等对反应前后的材料进行表征.结果表明,350-Ta@IrO_(x)在反应前后结构保持稳定,Ir溶解速率较未掺杂样品明显降低,证明了Ta掺杂大大提升了无定型氧化铱材料的稳定性.综上,本文发展了制备高价金属掺杂氧化铱的改性亚当斯熔融法,利用高价金属元素与氧的强成键作用,调控了铱活性位点的电子结构,同时提升了氧化铱类材料在酸性氧析出反应中的活性与稳定性,简化了此类材料的合成方式,为进一步降低质子交换膜电解水器件阳极催化剂的成本和提高其催化活性提供了新思路.
基金This work was supported by the National Natural Science Fund for Excellent Young Scientists Fund Program(Overseas)to Y.Z.,the National Key Research and Development Program of China(grant 2019YFA0906200)the Agricultural Science and Technology Innovation Program(CAAS-ZDRW202101)+1 种基金the Shenzhen Science and Technology Program(grant KQTD2016113010482651)the BMBF-funded de.
文摘Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,limiting the accessibility of the repetitive sequences,the centromeric and telomeric regions,and the study of inheritance of important agronomic traits in these regions.Here,we assembled a telomere-to-telomere(T2T)gap-free reference genome for the cultivar PN40024 using PacBio HiFi long reads.The T2T reference genome(PN_T2T)is 69 Mb longer with 9018 more genes identified than the 12X.v0 version.We annotated 67%repetitive sequences,19 centromeres and 36 telomeres,and incorporated gene annotations of previous versions into the PN_T2T assembly.We detected a total of 377 gene clusters,which showed associations with complex traits,such as aroma and disease resistance.Even though PN40024 derives from nine generations of selfing,we still found nine genomic hotspots of heterozygous sites associated with biological processes,such as the oxidation–reduction process and protein phosphorylation.The fully annotated complete reference genome therefore constitutes an important resource for grapevine genetic studies and breeding programs.
基金This work was supported by National Key R&D Program of China(2020YFE0204500)the National Natural Science Foundation of China(52273277,52072362,52071311)+1 种基金Jilin Province Science and Technology Development Plan Funding Project(20220201112GX)Youth Innovation Promotion Association CAS(2020230 and 2021223).H.X.Z.thanks funding from National Natural Science Foundation of China Outstanding Youth Science Foundation of China(Overseas).These authors thank the staff of beamline BL13SSW at Shanghai Synchrotron Radiation Facility for experiments supports.The authors also gratefully appreciate the support of the morphology characterization and analysis from Prof.Jiuhui Han(Tianjin University of Technology).
文摘Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotential and high current density.However,its precise synthesis and the understanding of synergisti-cally catalytic effects remain challenging.Herein,we report a facile method to synthesize the bimetallic Cu and Ni clusters anchored on porous carbon(Cu/Ni-NC)and achieve an enhanced ECO_(2)R.The aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy were employed to verify the metal dispersion and the coordination of Cu/Ni clusters on NC.As a result of this route,the target Cu/Ni-NC exhibits excellent electrocatalytic performance including a stable 30 h electrolysis at 200 mA cm^(-2) with carbon monoxide Faradaic efficiency of∼95.1%using a membrane electrode assembly electrolysis cell.Combined with the in situ analysis of the surface-enhanced Fourier transform infrared spectroelectrochemistry,we propose that the synergistic effects between Ni and Cu can effectively promote the H_(2)O dissociation,thereby accelerate the hydrogenation of CO_(2)to*COOH and the overall reaction process.
基金This work was financially supported the National Natural Science Foundation of China(Nos.21725103,51522101,51471075,51631004,51472232,51522202 and 21771013)Program for JLU Science and Technology Innovative Research Team(No.2017TD-09).
文摘Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe and N doping porous carb on n ematosphere(FeNPCN)as an excellent CO2RR electrocatalyst in aqueous electrolyte.Featuring with the high conductivity,pore structure and abundant Fe and N doping,FeNPCN exhibits high catalytic activity with a high faradaic selectivity of CO(94%)and long-term durability.Moreover,the ratio of CO and H2 can be changed by the applied potential for the different syngas related industry.Density functional theory(DFT)calculation results also reveal that the excellent catalytic activity is likely attributed to C and N hybrid coordination with atomic Fe.
文摘Efficient oxygen electrocatalysts are the key elements of numerous energy storage and conversion devices, including fuel cells and metal-air batteries. In order to realize their practical applications, highly efficient and inexpensive non-noble metal-based oxygen electrocatalysts are urgently required. Herein, we report a novel iron-chelated urea-formaldehyde resin hydrogel for the synthesis of Fe-N-C electrocatalysts. This novel hydrogel is prepared using a new instantaneous (20 s) one-step scalable strategy, which theoretically ensures the atomic-level dispersion of Fe ions in the urea-formaldehyde resin, guaranteeing the microstructural homogeneity of the electrocatalyst. Consequentl~ the prepared electrocatalyst exhibits higher catalytic activity and durability in the oxygen reduction (ORR) and evolution (OER) reactions than the commercial Pt/C catalyst. Furthermore, the above catalyst also shows a much better performance in rechargeable Zn-air batteries, including higher power density and better cycling stability. The developed synthetic approach opens up new avenues toward the development of sustainable active electrocatalysts for electrochemical energy devices.
基金This work is financially supported by the National Natural Science Foundation of China (Nos. 51472209, U1401241, 51522101, 51471075, 5163100, and 51401084), and Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20110061120040).
文摘The development of an electrocatalyst based on abundant elements for the oxygen evolution reaction (OER) is important for water splitting associated with renewable energy sources. In this study, we develop an interconnected Ni(Fe)OxHy nanosheet array on a stainless steel mesh (SSNNi) as an integrated OER electrode, without using any polymer binder. Benefiting from the well- defined three-dimensional (3D) architecture with highly exposed surface area, intimate contact between the active species and conductive substrate improved electron and mass transport capacity, facilitated electrolyte penetration, and improved mechanical stability. The SSNNi electrode also has excellent OER performance, including low overpotential, a small Tafel slope, and long-term durability in the alkaline electrolyte, making it one of the most promising OER electrodes developed.
基金supported by the National Natural Science Foundation of China(No.21725103)National Key R&D Program of China(No.2019YFA0705704)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA21010210)Jilin Province Science and Technology Development Plan Funding Project(No.20200201079JC)Changchun Science and Technology Development Plan Funding Project(No.19SS010)Jilin Province Capital Construction Funds Project(No.2020C026-1)the K.C.Wong Education Foundation(No.GJTD-2018-09).
文摘Electrochemical CO_(2) reduction reaction(CO_(2)RR)into value-added chemicals/fuels is crucial for realizing the sustainable carbon cycle while mitigating the energy crisis.However,it is impeded by the relatively high overpotential and low energy efficiency due to the lack of efficient electrocatalysts.Herein,we develop an isolated single-atom Ni catalyst regulated strategy to activate and stabilize the iron phthalocyanine molecule(Ni SA@FePc)toward a highly efficient CO_(2)RR process at low overpotential.The well-defined and homogenous catalytic centers with unique structures confer Ni SA@FePc with a significantly enhanced CO_(2)RR performance compared to single-atom Ni catalyst and FePc molecule and afford the atomic understanding on active sites and catalytic mechanism.As expected,Ni SA@FePc exhibits a high selectivity of more significant Faraday efficiency(≥95%)over a wide potential range,a high current density of~252 mA·cm^(−2) at low overpotential(390 mV),and excellent long-term stability for CO_(2)RR to CO.X-ray absorption spectroscopy measurement and theoretical calculation indicate the formation of NiN_(4)-O_(2)-FePc heterogeneous structure for Ni SA@FePc.And CO_(2)RR prefers to occur at the raised N centers of NiN4-O_(2)-FePc heterogeneous structure for Ni SA@FePc,which enables facilitated adsorption of*COOH and desorption of CO,and thus accelerated overall reaction kinetics.