Aqueous zinc-based batteries(ZBBs)are promising for grid-scale energy storage owing to their safety and cost-effectiveness;however,their practical application is hindered by rapid capacity fading and unstable cathodes...Aqueous zinc-based batteries(ZBBs)are promising for grid-scale energy storage owing to their safety and cost-effectiveness;however,their practical application is hindered by rapid capacity fading and unstable cathodes caused by sluggish Zn^(2+)kinetics and structural degradation in alkaline electrolytes.Herein,to address these challenges,we utilize amphiphilic polymer(PVP)to realize the composite of nickel-based complexes and ZIF-67.The hierarchical nickel-cobalt layered double hydroxide(NiCo-LDH)was prepared by metal ion exchange strategy.PVP-mediated-mediated suppression of agglomeration,combined with Ni^(2+)-induced framework reconstruction,synergistically modulated the morphology,resulting in mesoporous nanosheets with hydroxyl-rich surfaces.This design generated high-valence Co^(3+)species through charge-compensation-driven oxidation,thereby significantly accelerating Zn^(2+)ion diffusion and reducing the interfacial resistance.The optimized NiCo-LDH-100cathode(Ni:Co=3:1)achieves cycling stability and exceptional energy/power densities(0.49 mWh cm^(-2)/49.1 mW cm^(-2)).This study provides a solution for the cathode instability of Ni-Zn batteries through a coordination-derivatiz ation strategy,which is promising for advancing sustainable energy storage technologies.展开更多
The full utilization of active metal sites is meaningful for enhancing the application of materials in the energy storage field.In this study,a nickel-based nanosphere(NiSA-SSA-Co)precursor was obtained via effective ...The full utilization of active metal sites is meaningful for enhancing the application of materials in the energy storage field.In this study,a nickel-based nanosphere(NiSA-SSA-Co)precursor was obtained via effective doping based on a dual-ligand complex.With thermal activation,the pore microstructure of the precursor was modulated,and a transition state complex(NiSA-SSA-Co-350)was fabricated.NiSA-SSA-Co-350 not only retains part of the framework structure,but also fully exposes the metal nodes and enhances the efficiency of the active sites.NiSA-SSA-Co-350 exhibits optimal conductivity and intrinsic reactivity when applied as an electrode material for nickel-zinc batteries(NZBs).In contrast to the precursor,NiSA-SSA-Co-350with large specific surface area shows a higher specific capacity(0.30 mAh cm^(-2)at 3 mA cm^(-2)).This work hopefully provides a new perspective on the study of nanomaterial porosity in energy storage applications.展开更多
Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and ...Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and urea-rich wastewater purification;however,it remains a challenge to achieve overall urea electrolysis with high efficiency.Herein,we report a multifunctional electrocatalyst termed as Rh/Ni V-LDH,through integration of nickel-vanadium layered double hydroxide(LDH)with rhodium single-atom catalyst(SAC),to achieve this goal.The electrocatalyst delivers high HER mass activity of0.262 A mg^(-1) and exceptionally high turnover frequency(TOF)of 2.125 s^(-1) at an overpotential of100 m V.Moreover,exceptional activity toward urea oxidation is addressed,which requires a potential of 1.33 V to yield 10 mA cm^(-2),endorsing the potential to surmount the sluggish OER.The splendid catalytic activity is enabled by the synergy of the Ni V-LDH support and the atomically dispersed Rh sites(located on the Ni-V hollow sites)as evidenced both experimentally and theoretically.The selfsupported Rh/Ni V-LDH catalyst serving as the anode and cathode for overall urea electrolysis(1 mol L^(-1) KOH with 0.33 mol L^(-1) urea as electrolyte)only requires a small voltage of 1.47 V to deliver 100 mA cm^(-2) with excellent stability.This work provides important insights into multifunctional SAC design from the perspective of support sites toward overall electrolysis applications.展开更多
Electrocatalytic urea oxidation reaction(UOR)is regarded as an effective yet challenging approach for the degradation of urea in wastewater into harmless N2 and CO_(2).To overcome the sluggish kinetics,catalytically a...Electrocatalytic urea oxidation reaction(UOR)is regarded as an effective yet challenging approach for the degradation of urea in wastewater into harmless N2 and CO_(2).To overcome the sluggish kinetics,catalytically active sites should be rationally designed to maneuver the multiple key steps of intermediate adsorption and desorption.Herein,we demonstrate that metal-organic frameworks(MOFs)can provide an ideal platform for tailoring binary active sites to facilitate the rate-determining steps,achieving remarkable electrocatalytic activity toward UOR.Specifically,the MOF(namely,NiMn_(0.14)-BDC)based on Ni/Mn sites and terephthalic acid(BDC)ligands exhibits a low voltage of 1.317 V to deliver a current density of 10 mA cm^(-2).As a result,a high turnover frequency(TOF)of 0.15 s^(-1) is achieved at a voltage of 1.4 V,which enables a urea degradation rate of 81.87%in 0.33 M urea solution.The combination of experimental characterization with theoretical calculation reveals that the Ni and Mn sites play synergistic roles in maneuvering the evolution of urea molecules and key reaction intermediates during the UOR,while the binary Ni/Mn sites in MOF offer the tunability for electronic structure and d-band center impacting on the intermediate evolution.This work provides important insights into active site design by leveraging MOF platform and represents a solid step toward highly efficient UOR with MOF-based electrocatalysts.展开更多
基金financially supported by the National Natural Science Foundation of China(No.52371240)
文摘Aqueous zinc-based batteries(ZBBs)are promising for grid-scale energy storage owing to their safety and cost-effectiveness;however,their practical application is hindered by rapid capacity fading and unstable cathodes caused by sluggish Zn^(2+)kinetics and structural degradation in alkaline electrolytes.Herein,to address these challenges,we utilize amphiphilic polymer(PVP)to realize the composite of nickel-based complexes and ZIF-67.The hierarchical nickel-cobalt layered double hydroxide(NiCo-LDH)was prepared by metal ion exchange strategy.PVP-mediated-mediated suppression of agglomeration,combined with Ni^(2+)-induced framework reconstruction,synergistically modulated the morphology,resulting in mesoporous nanosheets with hydroxyl-rich surfaces.This design generated high-valence Co^(3+)species through charge-compensation-driven oxidation,thereby significantly accelerating Zn^(2+)ion diffusion and reducing the interfacial resistance.The optimized NiCo-LDH-100cathode(Ni:Co=3:1)achieves cycling stability and exceptional energy/power densities(0.49 mWh cm^(-2)/49.1 mW cm^(-2)).This study provides a solution for the cathode instability of Ni-Zn batteries through a coordination-derivatiz ation strategy,which is promising for advancing sustainable energy storage technologies.
基金supported by the National Natural Science Foundation of China(52371240)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_3511)。
文摘The full utilization of active metal sites is meaningful for enhancing the application of materials in the energy storage field.In this study,a nickel-based nanosphere(NiSA-SSA-Co)precursor was obtained via effective doping based on a dual-ligand complex.With thermal activation,the pore microstructure of the precursor was modulated,and a transition state complex(NiSA-SSA-Co-350)was fabricated.NiSA-SSA-Co-350 not only retains part of the framework structure,but also fully exposes the metal nodes and enhances the efficiency of the active sites.NiSA-SSA-Co-350 exhibits optimal conductivity and intrinsic reactivity when applied as an electrode material for nickel-zinc batteries(NZBs).In contrast to the precursor,NiSA-SSA-Co-350with large specific surface area shows a higher specific capacity(0.30 mAh cm^(-2)at 3 mA cm^(-2)).This work hopefully provides a new perspective on the study of nanomaterial porosity in energy storage applications.
基金finically supported by the National Key R&D Program of China(2017YFE0120500)the National Natural Science Foundation of China(51972129,51702150,and 21725102)+2 种基金the Key Research and Development Program of Hubei(2020BAB079)Bintuan Science and Technology Program(2020DB002,and 2022DB009)the Science and Technology Innovation Committee Foundation of Shenzhen(JCYJ20210324141613032 and JCYJ20190809142019365)。
文摘Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and urea-rich wastewater purification;however,it remains a challenge to achieve overall urea electrolysis with high efficiency.Herein,we report a multifunctional electrocatalyst termed as Rh/Ni V-LDH,through integration of nickel-vanadium layered double hydroxide(LDH)with rhodium single-atom catalyst(SAC),to achieve this goal.The electrocatalyst delivers high HER mass activity of0.262 A mg^(-1) and exceptionally high turnover frequency(TOF)of 2.125 s^(-1) at an overpotential of100 m V.Moreover,exceptional activity toward urea oxidation is addressed,which requires a potential of 1.33 V to yield 10 mA cm^(-2),endorsing the potential to surmount the sluggish OER.The splendid catalytic activity is enabled by the synergy of the Ni V-LDH support and the atomically dispersed Rh sites(located on the Ni-V hollow sites)as evidenced both experimentally and theoretically.The selfsupported Rh/Ni V-LDH catalyst serving as the anode and cathode for overall urea electrolysis(1 mol L^(-1) KOH with 0.33 mol L^(-1) urea as electrolyte)only requires a small voltage of 1.47 V to deliver 100 mA cm^(-2) with excellent stability.This work provides important insights into multifunctional SAC design from the perspective of support sites toward overall electrolysis applications.
基金This work is finically supported by the National Key R&D Program of China(Grant No.2017YFE0120500)the National Natural Science Foundation of China(Grant Nos.51972129,21725102)+3 种基金the Bintuan Science and Technology Program(Grant Nos.2020DB002,2022DB009)the Key Research and Development Program of Hubei(Grant No.2020BAB079)the Science and Technology Innovation Committee Foundation of Shenzhen(Grant No.JCYJ20210324141613032)the Natural Science Foundation of Jiangsu Province of China(BK20211609).
文摘Electrocatalytic urea oxidation reaction(UOR)is regarded as an effective yet challenging approach for the degradation of urea in wastewater into harmless N2 and CO_(2).To overcome the sluggish kinetics,catalytically active sites should be rationally designed to maneuver the multiple key steps of intermediate adsorption and desorption.Herein,we demonstrate that metal-organic frameworks(MOFs)can provide an ideal platform for tailoring binary active sites to facilitate the rate-determining steps,achieving remarkable electrocatalytic activity toward UOR.Specifically,the MOF(namely,NiMn_(0.14)-BDC)based on Ni/Mn sites and terephthalic acid(BDC)ligands exhibits a low voltage of 1.317 V to deliver a current density of 10 mA cm^(-2).As a result,a high turnover frequency(TOF)of 0.15 s^(-1) is achieved at a voltage of 1.4 V,which enables a urea degradation rate of 81.87%in 0.33 M urea solution.The combination of experimental characterization with theoretical calculation reveals that the Ni and Mn sites play synergistic roles in maneuvering the evolution of urea molecules and key reaction intermediates during the UOR,while the binary Ni/Mn sites in MOF offer the tunability for electronic structure and d-band center impacting on the intermediate evolution.This work provides important insights into active site design by leveraging MOF platform and represents a solid step toward highly efficient UOR with MOF-based electrocatalysts.
