Journal Article

Visible-Light Driven TiO2 Photocatalyst Coated with Graphene Quantum Dots of Tunable Nitrogen Doping

Li, Hui-Jun, Qian, Dongjin, Wang, Xianying, Lyu, Bowen, Tian, Shiwei, Yang, Junhe, Sun, Xiong, Ou, Nanquan, Gui, Bojie

2019

Overview

Nitrogen doped graphene quantum dots (NGQDs) were successfully prepared via a hydrothermal method using citric acid and urea as the carbon and nitrogen precursors, respectively. Due to different post-treatment processes, the obtained NGQDs with different surface modifications exhibited blue light emission, while their visible-light absorption was obviously different. To further understand the roles of nitrogen dopants and N-containing surface groups of NGQDs in the photocatalytic performance, their corresponding composites with TiO2 were utilized to degrade RhB solutions under visible-light irradiation. A series of characterization and photocatalytic performance tests were carried out, which demonstrated that NGQDs play a significant role in enhancing visible-light driven photocatalytic activity and the carrier separation process. The enhanced photocatalytic activity of the NGQDs/TiO2 composites can possibly be attributed to an enhanced visible light absorption ability, and an improved separation and transfer rate of photogenerated carriers.

• Publisher: MDPI AG,MDPI
• Subject: Carbon / Catalysis / Efficiency / Electric properties / Energy / Environmental impact / Fourier transforms / Graphene / Graphite - chemistry / Light / N-doping GQDs / Nitrogen / Nitrogen - chemistry / Photocatalysis / photocatalytic / Photochemical Processes / Quantum Dots / RhB degradation / Spectroscopy, Fourier Transform Infrared / Spectrum analysis / surface modification / Surface Properties / Titanium - chemistry / titanium dioxide / X-Ray Diffraction