Establishing an energy-saving and affordable hydrogen production route from infinite seawater presents a promising strategy for achieving carbon neutrality and low-carbon development.Compared with the kinetically slug...Establishing an energy-saving and affordable hydrogen production route from infinite seawater presents a promising strategy for achieving carbon neutrality and low-carbon development.Compared with the kinetically sluggish oxygen evolution reaction(OER),the thermodynamically advantageous sulfion oxidation reaction(SOR)enables the S^(2-)pollutants recovery while reducing the energy input of water electrolysis.Here,a nanoporous NiMo alloy ligament(np-NiMo)with AlNi_(3)/Al_(5)Mo heterostructure was prepared for hydrogen evolution reaction(HER,-0.134V versus reversible hydrogen electrode(vs.RHE)at 50mA/cm^(2)),which needs an Al_(89)Ni_(10)Mo_(1)as a precursor and dealloying operation.Further,the np-NiMo alloy was thermal-treated with S powder to generate Mo-doped NiS_(2)(np-NiMo-S)for OER(1.544V vs.RHE at 50mA/cm^(2))and SOR(0.364 V vs.RHE at 50mA/cm^(2)),while still maintaining the nanostructuring advantages.Moreover,for a two-electrode electrolyzer system with np-NiMo cathode(1M KOH+seawater)coupling np-NiMo-S anode(1mol/L KOH+seawater+1 mol/L Na_(2)S),a remarkably ultra-low cell potential of 0.532 V is acquired at 50mA/cm^(2),which is about 1.015 V below that of normal alkaline seawater splitting.The theory calculations confirmed that the AlNi_(3)/Al_(5)Mo heterostructure within np-NiMo promotes H_(2)O dissociation for excellent HER,while the Mo-dopant of np-NiMo-S lowers energy barriers for the rate-determining step from^(*)S_(4)to^(*)S_(8).This work develops two kinds of NiMo alloy with tremendous prominence for achieving energy-efficient hydrogen production from alkaline seawater and sulfur recycling from sulfion-rich sewage.展开更多
NiMo catalyst exhibits excellent catalytic performance in the electrooxidation of 5-hydroxymethylfurfural(HMF)to produce high-value 2,5-furandicarboxylic acid(FDCA).Although metallic nickel is known to undergo reconst...NiMo catalyst exhibits excellent catalytic performance in the electrooxidation of 5-hydroxymethylfurfural(HMF)to produce high-value 2,5-furandicarboxylic acid(FDCA).Although metallic nickel is known to undergo reconstruction into high-valent species during the reaction,the dynamic evolution of molybdenum components in NiMo catalyst and their mechanistic roles in catalytic reaction remain unclear.In this study,the structural evolution of NiMo alloy during HMF electrooxidation is systematically investigated.Operando analyses reveal that under anodic polarization,molybdenum undergoes oxidative dissolution in the form of MoO_(4)^(2-),concurrently driving the generation of high-valent Ni^(3+)species.Meanwhile,the dissolved MoO_(4)^(2-)re-adsorbs on the catalyst surface,forming a unique interfacial structure with Ni^(3+).Electrochemical results demonstrate that this surface structure facilitates a synergistic effect between the MoO_(4)^(2-)and high-valent Ni^(3+),enhancing the adsorption and activation of HMF molecules.Therefore,the NiMo alloy exhibits excellent catalytic performance,with a high FDCA selectivity of 99.0%.This study provides new insights into the relationship between the catalyst reconstruction process and enhancement of catalytic performance.展开更多
基金financially supported by the Guangxi Natural Science Fund for Distinguished Young Scholars(No.2024GXNSFFA010008)the Natural Science Foundation of Jilin Province of China(No.20240101098JC)the National Natural Science Foundation of China(No.22469002)。
文摘Establishing an energy-saving and affordable hydrogen production route from infinite seawater presents a promising strategy for achieving carbon neutrality and low-carbon development.Compared with the kinetically sluggish oxygen evolution reaction(OER),the thermodynamically advantageous sulfion oxidation reaction(SOR)enables the S^(2-)pollutants recovery while reducing the energy input of water electrolysis.Here,a nanoporous NiMo alloy ligament(np-NiMo)with AlNi_(3)/Al_(5)Mo heterostructure was prepared for hydrogen evolution reaction(HER,-0.134V versus reversible hydrogen electrode(vs.RHE)at 50mA/cm^(2)),which needs an Al_(89)Ni_(10)Mo_(1)as a precursor and dealloying operation.Further,the np-NiMo alloy was thermal-treated with S powder to generate Mo-doped NiS_(2)(np-NiMo-S)for OER(1.544V vs.RHE at 50mA/cm^(2))and SOR(0.364 V vs.RHE at 50mA/cm^(2)),while still maintaining the nanostructuring advantages.Moreover,for a two-electrode electrolyzer system with np-NiMo cathode(1M KOH+seawater)coupling np-NiMo-S anode(1mol/L KOH+seawater+1 mol/L Na_(2)S),a remarkably ultra-low cell potential of 0.532 V is acquired at 50mA/cm^(2),which is about 1.015 V below that of normal alkaline seawater splitting.The theory calculations confirmed that the AlNi_(3)/Al_(5)Mo heterostructure within np-NiMo promotes H_(2)O dissociation for excellent HER,while the Mo-dopant of np-NiMo-S lowers energy barriers for the rate-determining step from^(*)S_(4)to^(*)S_(8).This work develops two kinds of NiMo alloy with tremendous prominence for achieving energy-efficient hydrogen production from alkaline seawater and sulfur recycling from sulfion-rich sewage.
基金supported by the Natural Science Foundation of Guangxi Zhuang(2022JJD120011)the National Natural Science Foundation of China(22479031,22162004)the Project for Enhancing Young and Middle-aged Teacher's Research Basis Ability in Colleges of Guangxi(2025KY0040).
文摘NiMo catalyst exhibits excellent catalytic performance in the electrooxidation of 5-hydroxymethylfurfural(HMF)to produce high-value 2,5-furandicarboxylic acid(FDCA).Although metallic nickel is known to undergo reconstruction into high-valent species during the reaction,the dynamic evolution of molybdenum components in NiMo catalyst and their mechanistic roles in catalytic reaction remain unclear.In this study,the structural evolution of NiMo alloy during HMF electrooxidation is systematically investigated.Operando analyses reveal that under anodic polarization,molybdenum undergoes oxidative dissolution in the form of MoO_(4)^(2-),concurrently driving the generation of high-valent Ni^(3+)species.Meanwhile,the dissolved MoO_(4)^(2-)re-adsorbs on the catalyst surface,forming a unique interfacial structure with Ni^(3+).Electrochemical results demonstrate that this surface structure facilitates a synergistic effect between the MoO_(4)^(2-)and high-valent Ni^(3+),enhancing the adsorption and activation of HMF molecules.Therefore,the NiMo alloy exhibits excellent catalytic performance,with a high FDCA selectivity of 99.0%.This study provides new insights into the relationship between the catalyst reconstruction process and enhancement of catalytic performance.
