Co₃O₄ coating is one of most studied transition metal oxide due to its wide application in many fields such as gas sensors, electrochromic thin films, supercapacitors, and solar selective absorber. Aqueous electrophoretic deposition (EPD), which is considered as a cost-effective and environment-friendly coating technology, was successfully employed in preparing nano-Co₃O₄ coating in this study. For the EPD process with the solid loading of 1 g L⁻¹, 2.0 mM nitric acid was employed as suitable additive and 5 V was employed as deposition voltage. The prepared nano-Co₃O₄ coating exhibited good film characteristics, which was proved by scanning electron microscopy (SEM) technology. The result suggests that a rapid preparation of nano-Co₃O₄ coating in aqueous dispersion system can be easily accomplished. Moreover, the optimum concentrations of the added nitric acid would increase with the solid loading of Co₃O₄ nanoparticle, but the growth rate of the former was obviously lower than that of the latter.

中文翻译：

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水相电泳沉积法制备纳米Co 3 O 4涂层的环保方法

Co ₃ O ₄涂层是被研究最多的过渡金属氧化物之一，因为它在气体传感器，电致变色薄膜，超级电容器和太阳能选择性吸收剂等许多领域得到了广泛的应用。水电泳沉积（EPD）被认为是一种经济高效且环保的涂层技术，在本研究中成功地用于制备纳米Co ₃ O ₄涂层。对于固含量为1 g L ^-1的EPD工艺，采用2.0 mM硝酸作为合适的添加剂，采用5 V作为沉积电压。制备的纳米Co ₃ O ₄扫描电镜（SEM）技术证明了该涂层具有良好的膜特性。结果表明可以容易地完成在水分散体系中快速制备纳米Co ₃ O ₄涂层。而且，添加硝酸的最佳浓度会随着Co ₃ O ₄纳米颗粒的固形物含量的增加而增加，但前者的生长速度明显低于后者。