Preparation Of Transition Metal Nanomaterials And Application In Energy Electrocatalysis

The excessive depletion of fossil energy and the resulting severe environmental pollution have motivated an intense demand for searching for clean alternative energy.In this paper,hydrogen and ammonia were prepared with electrocatalysis method,which is eco-friendly and sustainable.The method could meet the requirements of human society for renewable energy.It is important to choose economical and efficient electrocatalysts in the process.Transmit metal nanomaterials were prepared by hydrothermal method,electrochemical reduction or electrostatic spinning method.These materials were used as hydrogen evolution catalyst,oxygen evolution catalyst or nitrogen reduction reaction catalyst.Eletrocatalytic perforamance were improved through design new structure and optimization property of materials.Amorphous Cu–Co–P nanofilms was fabricated in situ electrochemical reduction on CuCo₂O₄ nanoarrays.The formed catalyst needs an overpotential of only 104 mV in 1.0M KOH when the current density is 20 mA cm^–2,which is lower than that of CuCo₂O₄nanoarray.Notably,this catalyst also shows good stability for at least 24 h and a Faradaic efficiency?FE?close to 100%.An interface-engineered electrocatalyst?Ni?OH?₂–Ni₂P/Ti?was prepared via facile electrodeposition of amorphous Ni?OH?₂ on Ni₂P surface,with greatly enhanced HER activity in alkaline solution.This hybrid material is capable of driving current density of10 mA cm² at a low overpotential of 57 mV in 1.0 M KOH,thus outperforming most reported nickel phosphide catalysts.Moreover,this electrolytic system can maintain its catalytic activity for 24 hours under the long-time durability test,representing a highly promising cost-effective HER electrocatalyst.NiCu-MOF nanosheet array on Ni foam was synthesized through a one-pot hydrothermal method as an OER catalyst.The catalyst exhibits a small overpotential of only 309 mV at 100 mA cm² in 1.0 M KOH.In addition,the catalytic activity remained stable for at least 22 h in 1.0 M KOH,and the turnover frequency?TOF?was calculated as 0.231 mol O₂ s^-1 at an overpotential of 400 mV.FeCoNiS doped FeOOH nanowire catalyst was synthesized on carbon cloth based on ion exchange method,which was used as oxygen evolution catalyst.In 1.0 M KOH solution,the overpotential is 220.5 mV when the current density is 10 mA cm^-2.The overpotential is 269.95 mV when the current density is 100mA cm^-2.The catalytic activity remained stable for at least 30 h in 1.0 M KOH.Electrocatalytic nitrogen reduction reaction?NRR?under ambient conditions is regarded as a promising substitute approach to Haber–Bosch process for artificial N₂fixation.In this communication,well-defined MnO nanocrystals encapsulated in carbon nanofibers?MnO-CNFs?was constructed via electrospinning method.MnO-CNFs behaves as an excellent non-noble-metal NRR electrocatalyst character for NH₃synthesis with a Faradaic efficiency of 1.52%in 0.1 M Na₂SO₄ solution under ambient conditions.Remarkably,it attains a high NH₃ formation rate of 35.9?g h^-1 mg^-1_cat and also shows excellent durability during the electrolysis and recycling test.In this paper,new transition metal catalysts were prepared through design new structure and optimization property of materials,which provide new materials and new ideas for the development of renewable clean energy and energy conversion technologies...