纳米NiO-Y复合阴极材料的制备及微生物电解池催化产氢性能

在Y分子筛的溶胶反应体系中加入碳球，经老化、水热晶化反应得到纳米Y分子筛，通过等体积浸渍（incipient-wetness impregnation，IWI）方式负载镍盐前驱体，经焙烧制备纳米NiO-Y复合材料，采用XRD、SEM、TEM、XPS、TG-DTG和N₂吸附-脱附等手段对其物理化学性质进行表征。结果表明，合成的NiO-Y复合材料样品的晶粒粒径为500 nm，具有微-介孔多级孔道结构。总比表面积达到774.3 m²/g，孔容为0.495 cm³/g，有利于暴露更多的活性位。通过线性扫描和塔菲尔曲线电化学测试评价发现，当镍盐负载量为30%（质量分数）时，纳米NiO-Y复合材料作为微生物电解池阴极具有较高的电催化活性。在运行周期内，样品的最大析氢电流密度达到22.87 A/m²，产气总量中H₂含量占73.71%，产氢效率为0.393 m³/（m³·d），与Pt/C阴极产氢效率相近。

Synthesis and electrochemical evaluation of nano-NiO-Y composite cathode material for hydrogen evolution in microbial electrolysis cell

Nano Y zeolites were synthesized by adding carbon spheres into the synthesis sol of Y zeolites subjected to aging and hydrothermal crystallization; nickel-salt precursors were then loaded by using an incipient-wetness impregnation (IWI) method. After calcination, the nano-NiO-Y composite were then characterized by means of XRD, SEM, TEM, XPS, TG-DTG, and N₂ adsorption-desorption techniques and its performance as the cathode material for hydrogen evolution in microbial electrolysis cell was then investigated. The results show that the nano-NiO-Y composite has a crystal size of 500 nm of size and multiple porous structure including micro and mesopores; the total surface area and pore volume of nano-NiO-Y composites are 774.3 m²/g and 0.495 cm³/g, respectively. The electrochemical tests of linear scanning voltammetry and Tafel plots show that as microbial electrolytic cell (MEC) cathode, the nano-NiO-Y composite with a nickel-salt loading of 30% exhibits high electrocatalytic activity. In a continuous operation cycle, the largest hydrogen evolution current density of the nano-NiO-Y composites reaches 22.87 A/m², and the H₂ content is about 73.71% in total gas. The hydrogen production efficiency is 0.393 m³/(m³·d), comparable to that of Pt/C cathode.