Two-dimensional highly oxidized ilmenite nanosheets equipped with Z-scheme heterojunction for regulating tumor microenvironment and enhancing reactive oxygen species generation

Publication date: Available online 21 February 2020Source: Chemical Engineering JournalAuthor(s): Meitong Ou, Chao Pan, Yongkang Yu, Xuan Wang, Yun Zhou, Hanjie Zhang, Qinzhen Cheng, Meiying Wu, Xiaoyuan Ji, Lin MeiAbstractExcessive reactive oxygen species (ROS), as effective cancer therapeutic agents, can promote tumor apoptosis. However, the clinical applications of ROS-mediated cancer therapies still have many limitations, such as self-defects of traditional photosensitizer, adverse tumor microenvironment (TME), and insufficient ROS production. Here, two-dimensional and highly oxidized ilmenite nanosheets (HOIL NSs, formula: FeTiO3@Fe2O3), one of perovskite analogues, were developed through combining ball-milling, probe sonication assisted liquid exfoliation, and probe sonication assisted surface oxidation. The HOIL NSs with surface oxidized Fe2O3 shell and FeTiO3 core cleverly developed a direct Z-scheme heterojunction, in which much stronger oxidation and reduction potentials in the valence band (VB) of Fe2O3 and the conduction band (CB) of FeTiO3 respectively were obtained via recombining the electrons in the CB of Fe2O3 with the holes in the VB of FeTiO3. Under irradiation of 650 nm laser, the generation of ·O2− from O2 and ·OH from OH− on the CB of FeTiO3 and VB of Fe2O3, respectively, were enhanced largely. Besides, the Fe2O3 shell and Fe3+/Fe2+ inside HOIL NSs can not only damage the TME through glutathione consumption and O2 production, but also produce ·OH ...
Source: Chemical Engineering Journal - Category: Chemistry Source Type: research