The conversion of nitrogen oxide (NO) by photocatalysis is promising to solve the increasingly serious air pollution. Herein, raspberry-like TiO₂ hollow spheres consisting of small nanocrystals (less than 10 nm) were created using hollow carbon spheres as templates by controlling the synthesis parameters. These raspberry-like hollow spheres were well dispersed and revealed large specific surface area (172.6 m² g⁻¹) which was about 3 times that of commercial TiO₂ powders (P25). The raspberry-like hollow spheres with an anatase phase composition and high crystallinity revealed high NO₂ selectivity for NO conversion. Compared with P25, the hollow spheres exhibited excellent removal performance and high stability for NO, in which ∼60% of NO at a concentration of 600 ppb was removed while P25 removed ∼40% of NO. This is ascribed to the large specific surface area and pore volume, exposed (001) facets with high energy, and the reflection and scattering of light in the hollow sphere structure improving the utilization of light. Based on the diffuse reflection spectra, Mott–Schottky curves, and band gap structures, the removal mechanism is discussed.

中文翻译：

---

由小纳米晶体组成的树莓状 TiO2 空心球，可有效去除 NO

通过光催化转化氮氧化物（NO）有望解决日益严重的空气污染。在此，通过控制合成参数，以空心碳球为模板，制备了由小纳米晶体（小于10 nm）组成的覆盆子状TiO _{2空心球。}这些覆盆子状中空球体分散良好，比表面积大（172.6 m ² g ^-1），约为商业TiO ₂粉末（P25）的3倍。具有锐钛矿相组成和高结晶度的覆盆子状空心球显示出高 NO ₂NO 转化的选择性。与 P25 相比，空心球对 NO 表现出优异的去除性能和较高的稳定性，其中在 600 ppb 浓度下去除了约 60% 的 NO，而 P25 去除了约 40% 的 NO。这归因于较大的比表面积和孔体积，高能量的暴露（001）晶面，以及中空球结构中光的反射和散射，提高了光的利用率。基于漫反射光谱、莫特-肖特基曲线和带隙结构，讨论了去除机制。