Research Center for Combustion and Environmental Technology, Shanghai Jiao Tong University, Shanghai 200240, China.
Research Center for Combustion and Environmental Technology, Shanghai Jiao Tong University, Shanghai 200240, China.
J Environ Sci (China). 2023 Oct;132:1-11. doi: 10.1016/j.jes.2022.09.030. Epub 2022 Sep 27.
Non-thermal plasma (NTP) has been demonstrated as one of the promising technologies that can degrade volatile organic compounds (VOCs) under ambient condition. However, one of the key challenges of VOCs degradation in NTP is its relatively low mineralization rate, which needs to be addressed by introducing catalysts. Therefore, the design and optimization of catalysts have become the focus of NTP coupling catalysis research. In this work, a series of two-dimensional nanosheet Co-Ni metal oxides were synthesized by microwave method and investigated for the catalytic oxidation of benzene in an NTP-catalysis coupling system. Among them, CoNiO achieves 60% carbon dioxide (CO) selectivity (S) when the benzene removal efficiency (RE) reaches more than 99%, which is a significant enhancement compared with the CO selectivity obtained without any catalysts (38%) under the same input power. More intriguingly, this S is also significantly higher than that of single metal oxides, NiO or CoO, which is only around 40%. Such improved performance of this binary metal oxide catalyst is uniquely attributed to the synergistic effects of Co and Ni in CoNiO catalyst. The introduction of CoNiO was found to promote the generation of acrolein significantly, one of the key intermediates found in NTP alone system reported previously, suggest the benzene ring open reaction is promoted. Compared with monometallic oxides NiO and CoO, CoNiO also shows higher active oxygen proportion, better oxygen mobility, and stronger low-temperature redox capability. The above factors result in the improved catalytic performance of CoNiO in the NTP coupling removal of benzene.
非热等离子体（NTP）已被证明是一种很有前途的技术，可以在环境条件下降解挥发性有机化合物（VOCs）。然而，NTP 中 VOCs 降解的一个关键挑战是其相对较低的矿化率，这需要通过引入催化剂来解决。因此，催化剂的设计和优化已成为 NTP 耦合催化研究的焦点。在这项工作中，通过微波法合成了一系列二维纳米片 Co-Ni 金属氧化物，并将其用于 NTP 催化耦合系统中苯的催化氧化研究。其中，CoNiO 在苯去除效率（RE）超过 99%时达到 60%的二氧化碳（CO）选择性（S），与相同输入功率下没有任何催化剂时（38%）相比，这是一个显著的提高。更有趣的是，与单金属氧化物 NiO 或 CoO 相比，这种二元金属氧化物催化剂的 S 也显著提高，仅为 40%左右。这种二元金属氧化物催化剂的性能得到显著提高，这归因于 CoNiO 催化剂中 Co 和 Ni 的协同作用。发现引入 CoNiO 显著促进了丙烯醛的生成，丙烯醛是之前报道的 NTP 单独体系中发现的关键中间体之一，这表明苯环开环反应得到了促进。与单金属氧化物 NiO 和 CoO 相比，CoNiO 还表现出更高的活性氧比例、更好的氧迁移率和更强的低温氧化还原能力。这些因素导致 CoNiO 在 NTP 耦合去除苯中的催化性能得到提高。
