Significantly Enhanced Photoelectrocatalytic Alcohol Oxidation Performance of CdS Nanowire-Supported Pt <i>via</i> the “Bridge” Role of Nitrogen-Doped Graphene Quantum Dots
Zhilong He, Chen Yuan, Haifeng Gao, Zhigang Mou, Shaoping Qian, Chunyang Zhai, Cheng Lü
Abstract
Environmentally friendly, high energy conversion efficiency, and low pollution emission direct alcohol fuel cells (DAFCs) represent an ideal future clean renewable energy source. Herein, N-doped graphene quantum dots (N-GQDs) are introduced into cadmium sulfide (CdS) nanowires to form a “dot-on-nanowire” structure and support Pt nanoparticles to fabricate the electrode material, which is the core component of fuel cells. With the assistance of visible light irradiation, the as-prepared Pt-CdS/N-GQD electrode displays 2.7, 3.9, and 8.1 times improved electrocatalytic performance on methanol, ethanol, and ethylene glycol oxidation compared to the Pt-CdS one, respectively. Meanwhile, another essential parameter to evaluate the catalytic properties, the long-term stability of the corresponding electrode, is also significantly promoted under visible light illumination. The N-GQDs served as the “bridge” to link the photo- and electrocatalytic processes for facilitating efficacious interfacial charge transfer and the separation of photogenerated electron–hole pairs in the Pt-CdS/N-GQD electrode, which contributes to the synergistic effect of photoelectrocatalysis for the promotion of catalytic efficiency and stability. The present studies provide a promising avenue to design the high photoelectrocatalytic activity and superior poison resistance electrode materials for application in DAFCs.