Low Carbon Economy (LCE) Group, Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, Bandar Sunway, Selangor 46150, Malaysia.
Nanoscale Res Lett. 2013 Nov 6;8(1):465. doi: 10.1186/1556-276X-8-465.
Photocatalytic reduction of carbon dioxide (CO2) into hydrocarbon fuels such as methane is an attractive strategy for simultaneously harvesting solar energy and capturing this major greenhouse gas. Incessant research interest has been devoted to preparing graphene-based semiconductor nanocomposites as photocatalysts for a variety of applications. In this work, reduced graphene oxide (rGO)-TiO2 hybrid nanocrystals were fabricated through a novel and simple solvothermal synthetic route. Anatase TiO2 particles with an average diameter of 12 nm were uniformly dispersed on the rGO sheet. Slow hydrolysis reaction was successfully attained through the use of ethylene glycol and acetic acid mixed solvents coupled with an additional cooling step. The prepared rGO-TiO2 nanocomposites exhibited superior photocatalytic activity (0.135 μmol gcat-1 h-1) in the reduction of CO2 over graphite oxide and pure anatase. The intimate contact between TiO2 and rGO was proposed to accelerate the transfer of photogenerated electrons on TiO2 to rGO, leading to an effective charge anti-recombination and thus enhancing the photocatalytic activity. Furthermore, our photocatalysts were found to be active even under the irradiation of low-power energy-saving light bulbs, which renders the entire process economically and practically feasible.
将二氧化碳(CO2)光催化还原为甲烷等碳氢燃料是一种很有吸引力的策略,可以同时利用太阳能并捕获这种主要的温室气体。人们一直致力于制备基于石墨烯的半导体纳米复合材料作为用于各种应用的光催化剂。在这项工作中,通过一种新颖而简单的溶剂热合成路线制备了还原氧化石墨烯(rGO)-TiO2 杂化纳米晶。平均直径为 12nm 的锐钛矿 TiO2 颗粒均匀分散在 rGO 片上。通过使用乙二醇和乙酸混合溶剂并结合额外的冷却步骤,成功实现了缓慢的水解反应。与石墨氧化物和纯锐钛矿相比,所制备的 rGO-TiO2 纳米复合材料在 CO2 还原中表现出优异的光催化活性(0.135μmol gcat-1 h-1)。TiO2 与 rGO 之间的紧密接触被认为可以加速 TiO2 上光生电子向 rGO 的转移,从而有效抑制电荷复合,提高光催化活性。此外,我们的光催化剂在低功率节能灯泡的照射下也具有活性,这使得整个过程在经济和实际方面都是可行的。