Ragesh Nath R, Nethravathi C, Rajamathi Michael
Materials Research Group, Department of Chemistry, St. Joseph's College, 36 Lalbagh Road, Bangalore 560027, India.
Department of Chemistry, Mount Carmel College, 58 Palace Road, Vasanth Nagar, Bangalore 560052, India.
ACS Omega. 2021 Apr 28;6(18):12124-12132. doi: 10.1021/acsomega.1c00825. eCollection 2021 May 11.
Macroporous TiO monoliths were synthesized by self-sustained combustion reactions of molded pellets made up of a mixture of TiCl as a precursor, urea as a fuel, ammonium nitrate as an oxidizer, and starch as a binder. The porous TiO monoliths were found to be a heterostructure of anatase and rutile phases, in addition to being doped with carbon. Variation in the amount of starch yielded porous monoliths of different anatase-rutile ratios (increasing rutile component from 0 to 40%) but comparable Brunauer-Emmett-Teller (BET) surface area (∼30 m g). The porous monoliths obtained, where the TiCl/starch mass ratio was 2.17, exhibit exceptional photocatalytic activity in the degradation of dyes (methylene blue and methyl orange) and selective oxidation of benzyl alcohol to benzaldehyde under natural sunlight. The synergistic combination of high surface area, porous network, lowered band gap due to heterostructured anatase-rutile polymorphs, and the presence of doped carbon renders the macroporous TiO an efficient photocatalyst.
通过由作为前驱体的TiCl、作为燃料的尿素、作为氧化剂的硝酸铵以及作为粘合剂的淀粉的混合物制成的模压颗粒的自蔓延燃烧反应，合成了大孔TiO整体材料。除了掺杂有碳之外，发现该多孔TiO整体材料是锐钛矿相和金红石相的异质结构。淀粉用量的变化产生了不同锐钛矿-金红石比（金红石成分从0增加到40%）但具有可比的布鲁诺尔-埃米特-特勒（BET）表面积（约30 m²/g）的多孔整体材料。所获得的TiCl/淀粉质量比为2.17的多孔整体材料在自然光下对染料（亚甲基蓝和甲基橙）的降解以及将苯甲醇选择性氧化为苯甲醛方面表现出优异的光催化活性。高表面积、多孔网络、由于异质结构的锐钛矿-金红石多晶型物导致的带隙降低以及掺杂碳的存在的协同组合使得大孔TiO成为一种高效的光催化剂。
