Rational design of oxygen evolution reaction(OER)catalysts at low cost would greatly benefit the economy.Taking advantage of earth-abundant elements Si,Co and Ni,we produce a unique-structure where cobalt-nickel silic...Rational design of oxygen evolution reaction(OER)catalysts at low cost would greatly benefit the economy.Taking advantage of earth-abundant elements Si,Co and Ni,we produce a unique-structure where cobalt-nickel silicate hydroxide[Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)]is vertically grown on a reduced graphene oxide(rGO)support(CNS@rGO).This is developed as a low-cost and prospective OER catalyst.Compared to cobalt or nickel silicate hydroxide@rGO(CS@rGO and NS@rGO,respectively)nanoarrays,the bimetal CNS@rGO nanoarray exhibits impressive OER performance with an overpotential of 307 mV@10 mA cm^(-2).This value is higher than that of CS@rGO and NS@rGO.The CNS@rGO nanoarray has an overpotential of 446 mV@100 mA cm^(-2),about 1.4 times that of the commercial RuO_(2)electrocatalyst.The achieved OER activity is superior to the state-of-the-art metal oxides/hydroxides and their derivatives.The vertically grown nanostructure and optimized metal-support electronic interactions play an indispensable role for OER performance improvement,including a fast electron transfer pathway,short proton/electron diffusion distance,more active metal centers,as well as optimized dualatomic electron density.Taking advantage of interlay chemical regulation and the in-situ growth method,the advanced-structural CNS@rGO nanoarrays provide a new horizon to the rational and flexible design of efficient and promising OER electrocatalysts.展开更多
A novel 3 D compound, [H 0.5 CoP 0.5 O 2.5 ], was hydrothermally synthesized and structurally characterized by singly crystal X ray diffraction, ICP, elemental analysis and IR spectra. The compound crystallizes in ort...A novel 3 D compound, [H 0.5 CoP 0.5 O 2.5 ], was hydrothermally synthesized and structurally characterized by singly crystal X ray diffraction, ICP, elemental analysis and IR spectra. The compound crystallizes in orthorhombic system, space group Pnnm with a =0.805 1(2) nm, b =0.838 09(13) nm, \{ c =\}0.595 0(2) nm, V =0.401(2) nm 3, Z=1, D =1.669 Mg/cm 3, R=0.049 1, wR =0.153 2.展开更多
利用快速热压烧结法制备了Bi2Te2.5Se0.5热电合金。通过XRD、SEM、四点探针法以及热电材料测试仪等分析了合金试片的微观结构与热电性能。结果表明:二次热压烧结后合金内部的晶粒具有特殊的排列方向,这可增强其热电性能。经二次热压烧结...利用快速热压烧结法制备了Bi2Te2.5Se0.5热电合金。通过XRD、SEM、四点探针法以及热电材料测试仪等分析了合金试片的微观结构与热电性能。结果表明:二次热压烧结后合金内部的晶粒具有特殊的排列方向,这可增强其热电性能。经二次热压烧结后,合金的室温电导率增至700 S/cm,塞贝克系数维持在-200μV/K左右,故其室温功率因子可增至2.9 m W/(m·K^2)。通过计算得出二次烧结后其热电优值在325~425 K时皆大于1。展开更多
基金supported by the Fundamental Research Funds for the Central Universities(DUT21LK34)Natural Science Foundation of Liaoning Province(2020-MS-113).
文摘Rational design of oxygen evolution reaction(OER)catalysts at low cost would greatly benefit the economy.Taking advantage of earth-abundant elements Si,Co and Ni,we produce a unique-structure where cobalt-nickel silicate hydroxide[Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)]is vertically grown on a reduced graphene oxide(rGO)support(CNS@rGO).This is developed as a low-cost and prospective OER catalyst.Compared to cobalt or nickel silicate hydroxide@rGO(CS@rGO and NS@rGO,respectively)nanoarrays,the bimetal CNS@rGO nanoarray exhibits impressive OER performance with an overpotential of 307 mV@10 mA cm^(-2).This value is higher than that of CS@rGO and NS@rGO.The CNS@rGO nanoarray has an overpotential of 446 mV@100 mA cm^(-2),about 1.4 times that of the commercial RuO_(2)electrocatalyst.The achieved OER activity is superior to the state-of-the-art metal oxides/hydroxides and their derivatives.The vertically grown nanostructure and optimized metal-support electronic interactions play an indispensable role for OER performance improvement,including a fast electron transfer pathway,short proton/electron diffusion distance,more active metal centers,as well as optimized dualatomic electron density.Taking advantage of interlay chemical regulation and the in-situ growth method,the advanced-structural CNS@rGO nanoarrays provide a new horizon to the rational and flexible design of efficient and promising OER electrocatalysts.
文摘A novel 3 D compound, [H 0.5 CoP 0.5 O 2.5 ], was hydrothermally synthesized and structurally characterized by singly crystal X ray diffraction, ICP, elemental analysis and IR spectra. The compound crystallizes in orthorhombic system, space group Pnnm with a =0.805 1(2) nm, b =0.838 09(13) nm, \{ c =\}0.595 0(2) nm, V =0.401(2) nm 3, Z=1, D =1.669 Mg/cm 3, R=0.049 1, wR =0.153 2.
文摘利用快速热压烧结法制备了Bi2Te2.5Se0.5热电合金。通过XRD、SEM、四点探针法以及热电材料测试仪等分析了合金试片的微观结构与热电性能。结果表明:二次热压烧结后合金内部的晶粒具有特殊的排列方向,这可增强其热电性能。经二次热压烧结后,合金的室温电导率增至700 S/cm,塞贝克系数维持在-200μV/K左右,故其室温功率因子可增至2.9 m W/(m·K^2)。通过计算得出二次烧结后其热电优值在325~425 K时皆大于1。