Guo Yiwen, Gao Peng, Han Qi, Feng Li, Zhang Liqiu
Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
Chemosphere. 2025 Feb;371:144051. doi: 10.1016/j.chemosphere.2024.144051. Epub 2025 Jan 8.
Photocatalytic oxidation is considered to be a highly promising technology for indoor formaldehyde (HCHO) abatement. However, powdered photocatalysts encounter practical challenges due to their recycling difficulties and propensity for aggregation. In this study, we developed a CuO/OVs-TiO photocatalyst dispersion using various physical and chemical methods, which could be stabilized for an extended period. Subsequently, this catalyst was applied as a coating on nonwoven wallpaper (WP) to fabricate a novel CuO/OVs-TiO/WP composite which exhibited efficient photocatalytic performance in degrading gaseous HCHO under visible light irradiation. The physicochemical properties, photocatalytic activity and degradation mechanism of CuO/OVs-TiO/WP were systematically investigated through adsorption-photocatalytic degradation experiments, in-situ diffuse reflectance Fourier transform infrared spectroscopy (in-situ DRIFTS), and other analytical techniques. Results showed that the adsorption capacity of CuO/OVs-TiO/WP was 1.94 and 1.23 times higher than that of the individual photocatalyst or wallpaper, respectively. In addition, after 180 min of visible light irradiation, the HCHO removal rate achieved by CuO/OVs-TiO/WP reached 76.26%, representing a 52.54% enhancement compared to WP alone. Free radical quenching experiments and in-situ DRIFTS measurements were employed to elucidate the mechanism of photocatalytic oxidation of HCHO. It was found that hydroxyl radical (·OH) played a ruling role in HCHO decomposition, with HCHO initially oxidized to dioxymethylene (DOM), subsequently converted to formate species, and ultimately oxidized to carbonate or HO and CO. Furthermore, the degradation of HCHO by CuO/OVs-TiO/WP remained above 65% after five cycles, demonstrating a cycling stability of 86.88%. This study provides valuable insights for the photocatalytic treatment of indoor HCHO.
光催化氧化被认为是一种极具前景的室内甲醛（HCHO）去除技术。然而，粉末状光催化剂由于回收困难和易于聚集而面临实际挑战。在本研究中，我们使用各种物理和化学方法开发了一种CuO/OVs-TiO光催化剂分散体，其可以长期稳定。随后，将该催化剂作为涂层应用于非织造壁纸（WP）上，制备了一种新型的CuO/OVs-TiO/WP复合材料，该复合材料在可见光照射下对气态HCHO具有高效的光催化降解性能。通过吸附-光催化降解实验、原位漫反射傅里叶变换红外光谱（原位DRIFTS）和其他分析技术，系统地研究了CuO/OVs-TiO/WP的物理化学性质、光催化活性和降解机理。结果表明，CuO/OVs-TiO/WP的吸附容量分别比单独的光催化剂或壁纸高1.94倍和1.23倍。此外，在可见光照射180分钟后，CuO/OVs-TiO/WP实现的HCHO去除率达到76.26%，与单独的WP相比提高了52.54%。采用自由基猝灭实验和原位DRIFTS测量来阐明HCHO光催化氧化的机理。发现羟基自由基（·OH）在HCHO分解中起主导作用，HCHO最初被氧化为二氧亚甲基（DOM），随后转化为甲酸盐物种，最终被氧化为碳酸盐或HO和CO。此外，CuO/OVs-TiO/WP在五个循环后对HCHO的降解率仍保持在65%以上，循环稳定性为86.88%。本研究为室内HCHO的光催化处理提供了有价值的见解。
