Su Yang, Li Hongfei, Ma Hanbin, Wang Hua, Robertson John, Nathan Arokia
Department of Engineering, University of Cambridge, Cambridge CB3 0FA, U.K.
Jiangsu Province Environment Monitoring Centre, Nanjing 210036, China.
ACS Omega. 2018 Feb 14;3(2):1939-1945. doi: 10.1021/acsomega.7b01612. eCollection 2018 Feb 28.
Amorphous Cu O nanoflakes with a thickness of 10-50 nm were synthesized through dye-assisted transformation of rhombic dodecahedral CuO nanocrystals using a facile solution process. The morphology evolution observed by electron microscopy is highly dependent on the reaction between the surface and the dye. The crystal grain shrinks during the process until the formation of a purely amorphous nanoflake. The amorphous Cu O nanoflake consists of a combination of Cu(I) and Cu(II) with a ratio close to 1:1. It shows enhanced photocatalytic reactivity toward the degradation of methyl orange compared to that of rhombic dodecahedral CuO nanocrystals with all active (110):Cu facets. The chemical composition and architecture remain the same after repeating degradation tests. The high surface-to-volume ratio contributes to its superior photocatalytic performance, whereas its low surface energy, confirmed by density functional theory simulations, explains its improved stability. The nanoflakes also show the ability of degrading nitrobenzene effectively, thus demonstrating great promise as a highly stable and active photocatalyst for environmental applications.
通过一种简便的溶液法，利用染料辅助菱形十二面体CuO纳米晶体的转变，合成了厚度为10 - 50 nm的非晶态Cu₂O纳米片。通过电子显微镜观察到的形貌演变高度依赖于表面与染料之间的反应。在此过程中晶粒收缩，直至形成纯非晶态纳米片。非晶态Cu₂O纳米片由比例接近1:1的Cu(I)和Cu(II)组成。与具有所有活性(110):Cu晶面的菱形十二面体CuO纳米晶体相比，它对甲基橙的降解表现出增强的光催化反应活性。重复降解测试后，其化学成分和结构保持不变。高的表面体积比有助于其优异的光催化性能，而密度泛函理论模拟证实的低表面能解释了其提高的稳定性。这些纳米片还表现出有效降解硝基苯的能力，因此作为一种用于环境应用的高度稳定且活性高的光催化剂具有巨大潜力。
