Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul, 04763, Republic of Korea.
Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul, 04763, Republic of Korea.
Environ Res. 2024 Nov 1;260:119664. doi: 10.1016/j.envres.2024.119664. Epub 2024 Jul 22.
The preparation of nitrogen-doped TiO (i.e., N-TiO) catalysts is a highly effective option to improve the photocatalytic activity of TiO. Nonetheless, relatively little is known about the effects of dopant precursors selected for their preparation with regard to the photocatalytic efficacy. In this study, three types of dopants are selected and used as N sources (urea (U), melamine (M), and aqueous ammonia (A)) for N-TiO samples with the name codes of NTU, NTM, and NTA, respectively. The photocatalytic efficacy of these N-TiO samples is examined against toluene in a packed bed flow reactor. Under optimal conditions (e.g., relative humidity (RH) = 20% and gas hourly space velocity (GHSV) = 1698 h), the superiority of NTA is evident over others with a quantum efficiency (QE) of 7.03 × 10 molecules photon, a space time yield (STY) of 1.38 × 10 molecules photon mg, and a specific clean air delivery rate (SCADR) of 1148.8 L g h. The analysis based on in-situ diffuse reflectance infrared Fourier transform spectroscopy and gas chromatography-mass spectrometry confirms the formation of several intermediates such as benzyl alcohol, benzaldehyde, benzoic acid, and alkane species through ring opening reactions. In addition, the prepared NTA photocatalyst exhibits the highest toluene photocatalytic degradation efficiency among all TiO-based catalysts surveyed to date. Overall, this study offers as a valuable guideline for the development of advanced TiO catalytic systems (such as N-TiO) for the treatment of aromatic hydrocarbons in indoor air.
氮掺杂 TiO（即 N-TiO）催化剂的制备是提高 TiO 光催化活性的一种非常有效的方法。然而，对于选择用于制备的掺杂前体对光催化效果的影响，人们知之甚少。在这项研究中，选择了三种类型的掺杂剂作为 N 源（尿素 (U)、三聚氰胺 (M) 和氨水 (A)），分别用于制备 N-TiO 样品，其名称代码为 NTU、NTM 和 NTA。在填充床流动反应器中，使用甲苯作为目标污染物来评估这些 N-TiO 样品的光催化效果。在最佳条件下（例如，相对湿度 (RH) = 20%和气体时空速度 (GHSV) = 1698 h），NTA 的优势明显优于其他两种，其量子效率 (QE) 为 7.03×10 个光子分子、时空产率 (STY) 为 1.38×10 个光子分子 mg 和特定清洁空气输送率 (SCADR) 为 1148.8 L g h。基于原位漫反射红外傅里叶变换光谱和气相色谱-质谱分析证实了通过开环反应形成了几种中间体，如苄醇、苯甲醛、苯甲酸和烷烃。此外，所制备的 NTA 光催化剂在迄今为止研究的所有基于 TiO 的催化剂中表现出最高的甲苯光催化降解效率。总的来说，这项研究为开发用于处理室内空气中芳香烃的先进 TiO 催化系统（如 N-TiO）提供了有价值的指导。
