Son Bui Thanh, Long Nguyen Viet, Nhat Hang Nguyen Thi
Nanotechnology, Thu Dau Mot University Binh Duong Province Vietnam
RSC Adv. 2021 Sep 17;11(49):30805-30826. doi: 10.1039/d1ra05647f. eCollection 2021 Sep 14.
Metal oxides possess exceptional physicochemical properties which make them ideal materials for critical photocatalytic applications. However, of major interest, their photocatalytic applications are hampered by several drawbacks, consisting of prompt charge recombination of charge carriers, low surface area, inactive under visible light, and inefficient as well as expensive post-treatment recovery. The immobilization of metal oxide semiconductors on materials possessing high binding strength eliminates the impractical and costly recovery of spent catalysts in large-scale operations. Notably, the synthesis of green material (ash, clay, foundry sand, and pumice)-based metal oxides could provide a synergistic effect of the superior adsorption capacity of supporting materials and the photocatalytic activity of metal oxides. This phenomenon significantly improves the overall degradation efficiency of emerging pollutants. Inspired by the novel concept of "treating waste with waste", this contribution highlights recent advances in the utilization of natural material (clay mineral and pumice)- and waste material (ash and foundry sand)-based metal oxide nanocomposites for photodegradation of various pollutants. First, principles, mechanism, challenges towards using metal oxide as photocatalysts, and immobilization techniques are systematically summarized. Then, sources, classifications, properties, and chemical composition of green materials are briefly described. Recent advances in the utilization of green materials-based metal oxide composites for the photodegradation of various pollutants are highlighted. Finally, in the further development of green materials-derived photocatalysts, we underlined the current gaps that are worthy of deeper research in the future.
金属氧化物具有优异的物理化学性质，这使其成为关键光催化应用的理想材料。然而，主要问题在于，它们的光催化应用受到几个缺点的阻碍，包括电荷载流子的快速电荷复合、低表面积、在可见光下无活性以及后处理回收效率低且成本高。将金属氧化物半导体固定在具有高结合强度的材料上，消除了大规模操作中废催化剂不切实际且成本高昂的回收问题。值得注意的是，合成基于绿色材料（灰分、粘土、铸造砂和浮石）的金属氧化物可以产生协同效应，即支撑材料的优异吸附能力与金属氧化物的光催化活性相结合。这种现象显著提高了新兴污染物的整体降解效率。受“以废治废”这一新颖概念的启发，本文突出了利用天然材料（粘土矿物和浮石）以及废料（灰分和铸造砂）基金属氧化物纳米复合材料光降解各种污染物的最新进展。首先，系统总结了使用金属氧化物作为光催化剂的原理、机制、面临的挑战以及固定化技术。然后，简要描述了绿色材料的来源、分类、性质和化学成分。重点介绍了利用基于绿色材料的金属氧化物复合材料光降解各种污染物的最新进展。最后，在绿色材料衍生光催化剂的进一步发展方面，我们强调了当前存在的差距，这些差距在未来值得深入研究。
