Deqiang Feng,Jie He,Lingcheng Zheng,Wenjun Jiang,Ce Zhang,Long Li,Jian Song,Wei Yao
Developing novel catalysts and catalysis processes are highly attractive in environmental protection and energy utilization. Photocatalysis-Fenton combinational process is an environmentally friendly technology and has broad application prospects. In this work, thin Fe@α-Fe 2 O 3 nanosheets with thickness of 2–5 nm were designed by oxidation of Fe metal nanostructure synthesized using a modified solution reaction method. The nanosheet structure with thin thickness has short diffusion distance for the photogenerated carriers and prolongs the carriers' life. Simultaneously, the presence of Fe can reduce the resistance of system and further promote the transport and transfer of photogenerated carriers from the bulk to the surface, causing less carrier recombination and better photocatalytic performance. What's more, the Fe@α-Fe 2 O 3 composite can induce the Fenton-like reaction to generate active • OH radicals, which significantly improve the degradation rate . The synergistic effect of photocatalysis and Fenton processes makes the system show an enhanced photodegradation performance: 96.5% of RhB is degraded after 60 min visible light irradiation , especially, 84.3% of RhB is degraded within the first 10 min, which are much higher than that of the pure α-Fe 2 O 3 sample. This work demonstrates that the conjunction of photocatalysis and Fenton processes based on the Fe@α-Fe 2 O 3 nanosheets provides a potential application for pollutants degradation.
2D nonlayered materials have attracted more and more attention due to their novel properties and special surface structures. However, due to isotropic chemical bonds within the crystal, the synthesis of ultrathin 2D nonlayered materials is an urgent challenge. Herein, α -Fe 2 O 3 2D nanosheets as thin as ≈8.2 nm on different substrates using self-designed ultralow concentration precursors combined with Gibbs free energy and Se catalysts design are successfully synthesized. The thickness-dependent growth mechanism is systematically studied, demonstrating the thermodynamic and kinetic controlling factors. The as-grown α -Fe 2 O 3 nanosheets are demonstrated with single-crystal structures without any other elements doping. The α -Fe 2 O 3 nanosheets photodetectors show the reasonable response performance with the positive photoconductive mechanism. This improved chemical vapor deposition method provides a promising idea for the synthesis of ultrathin 2D nonlayered materials.