Lateral surface near the fracture of before and after oxide film removing tensile sample was examined by scanning electron The relationship between surface morphology and microscopy （SEM） microstructure was establis...Lateral surface near the fracture of before and after oxide film removing tensile sample was examined by scanning electron The relationship between surface morphology and microscopy （SEM） microstructure was established. The results show that the microcracks are caused by brittleness rupture of surface oxide films due to α lamellas sliding along α lamella boundaries. And the sliding of aligned α lamellas bring not only microcrack formation but also the raise of colony relative to prior sample surface. A slip model, which depicts the relationship between surface morphology and microstructure, was brought forward to analyze the observation.展开更多
Hydrogen is considered to be an ideal safe and clean energy source,which can be produced by water splitting.The high overpotential of hydrogen evolution reaction(HER)is one of the bottleneck issues for the practical a...Hydrogen is considered to be an ideal safe and clean energy source,which can be produced by water splitting.The high overpotential of hydrogen evolution reaction(HER)is one of the bottleneck issues for the practical application of water splitting,where high-efficiency electrocatalysts are thus usually required to accommodate and facilitate the reaction.In recent years,a rapid rise in the HER electrocatalysts has been witnessed,especially nanostructured materials.Noble metals are generally regarded as the most effective electrocatalysts for HER,while some other electrocatalysts based on non-noble transition metals,including alloys,chalcogenides,phosphides,carbides and nitrides,can even approach the HER efficiency of noble metal benchmarks.This paper mainly introduces the basic principles of the HER process,evaluates different categories of nanostructured electrocatalytic materials,providing guidance for the design and fabrication of nanostructured HER catalysts.Moreover,recent progress and future research directions regarding the performance of metallic nanostructured materials are also discussed.展开更多
文摘Lateral surface near the fracture of before and after oxide film removing tensile sample was examined by scanning electron The relationship between surface morphology and microscopy （SEM） microstructure was established. The results show that the microcracks are caused by brittleness rupture of surface oxide films due to α lamellas sliding along α lamella boundaries. And the sliding of aligned α lamellas bring not only microcrack formation but also the raise of colony relative to prior sample surface. A slip model, which depicts the relationship between surface morphology and microstructure, was brought forward to analyze the observation.
基金financially supported by the National Science and Technology Major Project(No.2017-VI-0013-0085)the National Natural Science Foundation of China(No.52001205)Shanghai Sailing Program(No.19YF1422600)。
文摘Hydrogen is considered to be an ideal safe and clean energy source,which can be produced by water splitting.The high overpotential of hydrogen evolution reaction(HER)is one of the bottleneck issues for the practical application of water splitting,where high-efficiency electrocatalysts are thus usually required to accommodate and facilitate the reaction.In recent years,a rapid rise in the HER electrocatalysts has been witnessed,especially nanostructured materials.Noble metals are generally regarded as the most effective electrocatalysts for HER,while some other electrocatalysts based on non-noble transition metals,including alloys,chalcogenides,phosphides,carbides and nitrides,can even approach the HER efficiency of noble metal benchmarks.This paper mainly introduces the basic principles of the HER process,evaluates different categories of nanostructured electrocatalytic materials,providing guidance for the design and fabrication of nanostructured HER catalysts.Moreover,recent progress and future research directions regarding the performance of metallic nanostructured materials are also discussed.
