Department of Chemical Engineering, Hanyang University, Seoul, 04763, Republic of Korea; Center for Creative Convergence Education, Hanyang University, Seoul, 04763, Republic of Korea; Clean-Energy Research Institute, Hanyang University, Seoul, 04763, Republic of Korea.
Department of Chemical Engineering, Hanyang University, Seoul, 04763, Republic of Korea.
Environ Res. 2023 Dec 15;239(Pt 2):117409. doi: 10.1016/j.envres.2023.117409. Epub 2023 Oct 12.
The lack of crystallinity of the aerogel materials has limited their significance which otherwise have found huge potential in wide variety of applications. In current work, we have developed TiO aerogels by solid-state gelation method using commercially available P25 and ST-01 (commercial Ishihara TiO Powder). The lack of crystallinity in the aerogel framework was resolved via utilizing crystalline TiO nanoparticles and the phase transformation was assessed as a function of phase composition. Via controlled solid-state gelation, surface area retention of 88.7% was achieved whereas the rutile-to-anatase weight fraction (W) was considerably enhanced to 0.50. Interestingly, the phase transformation occurred only in P25, which suggests the mixed phase (anatase + rutile) composition as prerequisite for successful phase transformation. Favorably, TiO aerogels imbibe high degree of oxygen vacancies (Vo) responsible for photocatalytic applications. Interestingly, Vo induction is higher for the TiO with anatase phase composition (ST-01) followed by the sample with mixed phase composition (P25). The developed TiO aerogel photocatalysts were employed to dye degradation of Rhodamine B (RhB) and Methylene Blue (MB). The samples attained 94.8% and 96.8% degradation efficiency within 15 min for RhB and MB with nearly 2-fold improvement in the photocatalytic efficiency compared to parent P25 TiO respectively.
气凝胶材料的非晶态特性限制了其应用，否则它们在各种应用中具有巨大的潜力。在目前的工作中，我们使用市售的 P25 和 ST-01（商用石原钛白粉）通过固态胶凝法制备了 TiO 气凝胶。通过使用结晶 TiO 纳米粒子解决了气凝胶骨架的非晶态问题，并评估了相组成对相转变的影响。通过控制固态胶凝，实现了 88.7%的表面积保留率，而锐钛矿-金红石重量分数（W）显著提高到 0.50。有趣的是，相转变仅在 P25 中发生，这表明混合相（锐钛矿+金红石）组成是成功相转变的前提。有利的是，TiO 气凝胶具有高度的氧空位（Vo），这使其适用于光催化应用。有趣的是，具有锐钛矿相组成（ST-01）的 TiO 诱导的 Vo 更高，其次是具有混合相组成（P25）的样品。所开发的 TiO 气凝胶光催化剂用于罗丹明 B（RhB）和亚甲基蓝（MB）的染料降解。对于 RhB 和 MB，样品在 15 分钟内分别达到了 94.8%和 96.8%的降解效率，与原始 P25 TiO 相比，光催化效率提高了近 2 倍。
