Abstract The preparation of efficient catalysts in hydrogen evolution reaction (HER) is an urgent task at present. In this work, Ni(OH)2/Ni/g-C3N4 composite catalyst was prepared through liquid phase impregnation with in-situ reduction, which was used to compose the cathode with carbon paper (CP) for the microbial electrolysis cell (MEC). With the help of SEM, TEM, XRD, XPS and electrochemical analysis techniques, the structure, properties and electrocatalytic performance in hydrogen evolution of the Ni(OH)2/Ni/g-C3N4 composite were investigated. The results indicate that the Ni(OH)2/Ni/g-C3N4 catalyst exhibits excellent electrochemical activity for hydrogen evolution in the MEC. Using the Ni(OH)2/Ni/g-C3N4 catalyst, the current density reaches 100 A/cm2 at a small overpotential of 1881 mV, with a low charge transfer resistance of 10.86 Ω and a low Tafel slope of 44.3 mV/dec, which is much superior to pure g-C3N4 catalyst and CP, and even comparable to the Pt catalyst, suggesting that the Ni(OH)2/Ni/g-C3N4 composite can be a potential candidate of HER catalyst in MEC.

中文翻译：

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Ni(OH)2/Ni/g-C3N4复合材料：一种高效的析氢电催化剂

摘要 制备高效的析氢反应（HER）催化剂是当前紧迫的任务。本工作通过液相浸渍原位还原制备了Ni(OH)2/Ni/g-C3N4复合催化剂，用于微生物电解槽(MEC)的碳纸(CP)组成阴极。 . 借助SEM、TEM、XRD、XPS和电化学分析技术，研究了Ni(OH)2/Ni/g-C3N4复合材料的结构、性质和电催化析氢性能。结果表明，Ni(OH)2/Ni/g-C3N4催化剂在MEC中表现出优异的析氢电化学活性。使用 Ni(OH)2/Ni/g-C3N4 催化剂，在 1881 mV 的小过电位下电流密度达到 100 A/cm2，电荷转移电阻低至 10。