一步溶剂热法生成Zr-Ni_(0.96)S/NF纳米材料用于高效电催化产氢反应研究

通过一步溶剂热法,在泡沫镍衬底(NF)上成功地制备了一种多功能电极材料,即含锆掺杂的镍硫化物(命名为Zr-Ni_(0.96)S/NF).通过调节锆源加入量,以优化样品微观结构和催化活性,结果表明:在锆源加入量为1 mmol时,得到的Zr-Ni_(0.96)S/NF纳米材料展现出均匀的纳米颗粒涂层结构.在1 M KOH溶液中,该材料表现出优异的HER(hydrogen evolution reaction)活性,在10 mA cm^(-2)电流密度下,其析氢过电位仅为95 mV,并且具有超过30小时的良好循环稳定性.当使用Zr-Ni_(0.96)S/NF同时作为阴极和阳极进行全解水时,它能够在1.98 V电压下产生200 mA cm^(-2)的电流密度,并具有15小时以上的循环稳定性,优于当前大多数非贵金属的电催化剂.

Earth-abundant amorphous catalysts for electrolysis of water

The generation of hydrogen through the electrolysis of water has attracted attention as a promising way to produce and store energy using renewable energy sources.In this process,a catalyst is very important to achieve a high‐energy conversion efficiency for the electrolysis of water.A good catalyst for water electrolysis should exhibit high catalytic activity,good stability,low cost and good scalability.Much research has been devoted to developing efficient catalysts for both the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Traditionally,it has been accepted that a material with high crystallinity is important to serve as a good catalyst for HER and/or OER.Recently,catalysts for HER and/or OER in the electrolysis of water splitting based on amorphous materials have received much interest in the scientific community owing to the abundant unsaturated active sites on the amorphous surface,which form catalytic centers for the reaction of the electrolysis of water.We summarize the recent advances of amorphous catalysts for HER,OER and overall water splitting by electrolysis and the related fundamental chemical reactions involved in the electrolysis of water.The current challenges confronting the electrolysis of water and the development of more efficient amorphous catalysts are also discussed.

Electrochemically formed PtFeNi alloy nanoparticles on defective NiFe LDHs with charge transfer for efficient water splitting

Efficient and stable bifunctional electrocatalysts for water splitting is essential for producing hydrogen and alleviating huge energy consumption.Meanwhile,charge transfer engineering is an efficient approach to modulate the localized electronic properties of catalysts and tune the electrocatalytic performance.Herein,we tactfully fabricate PtFeNi alloys/NiFe layered double hydroxides(LDHs)heterostructure by an easily electrochemical way with a small amount of Pt.The experimental and theoretical results unravel that the charge transfer on the alloy clusters modulated by the defective substrates(NiFe LDHs),which synergistically optimizes the adsorption energy of the reaction intermediates.The electrocatalyst exhibits an ultra‐low overpotential of 81 and 243 mV at the current density of 100 mA cm^(–2) for hydrogen evolution and oxygen evolution,respectively.Furthermore,the overall water splitting indicates that PtFeNi alloys/NiFe LDHs presents an ultra‐low overpotential of 265 and 406 mV to reach the current density of 10 and 300 mA cm^(–2),respectively.It proves that the PtFeNi alloys/NiFe LDHs catalyst is an excellent dual‐function electrocatalyst for water splitting and promising for industrialization.This work provides a new electrochemical approach to construct the alloy heterostructure.The prepared heterostructures act as an ideal platform to investigate the charge re‐distribution behavior and to improve the electrocatalytic activity.

3D Se-doped NiCoP nanoarrays on carbon cloth for efficient alkaline hydrogen evolution

The exploration of stable and highly efficient alkaline hydrogen evolution reaction(HER)electrocatalysts is imperative for alkaline water splitting.Herein,Se-doped NiCoP with hierarchical nanoarray structures directly grown on carbon cloth(Se-NiCoP/CC)was prepared by hydrothermal reaction and phosphorization/selenization process.The experimental results reveal that Se doping could increase the electrochemical active sites and alter the electronic structure of NiCoP.The optimized Se-NiCoP/CC electrode exhibits outstanding HER activity in alkaline electrolyte,which only needs a low overpotential of 79 mV at the current density of 10 mA/cm^(2).When serving as anode and cathode electrode simultaneously,the Se-NiCoP/CC electrodes achieve current density of 50 mA/cm^(2) at a low voltage of only 1.62 V.This work provides a feasible way to rationally design high active HER electrocatalysts.