Photoassisted Reduction Synthesis of Pt@SnO₂/Graphene Catalysts with Excellent Activities toward Methanol Oxidation

Abstract

Photoassisted reduction, as an indispensable supplement to traditional chemical reduction, is a significant technique for regulating the interfacial interaction of active substances in the hybrid electrocatalysts toward methanol oxidation reaction (MOR). In this work, the well-hierarchical heterostructure of Pt@SnO 2 / graphene was successfully developed through the usage of the first hydrothermal and subsequent ultraviolet light (UV) excitation process. It was found that Pt particles with an average diameter size of 2.41 nm could be effectively trapped on the surface of semiconducting SnO 2 nanocrystals (NCs). Besides, the small SnO 2 NCs with an even distribution provided great opportunities for the accessible regulation from UV irradiation, thus endowing them with high contents of oxygen vacancies, broadened valence band, and inseparably interfacial effect that contributed to the improvement of electrical conductivity for the composite catalysts. Benefitting from the synergistic effect from each component, the obtained catalysts not only displayed a large electrochemically active surface area (ECSA) value of 80.7 m 2 g −1 and excellent mass activity of 1833.6 mA mg −1 but also showed desirable long-term durability and poisoning tolerance. For the further enhancement of electrochemical performance, electro-photo synergistic catalysis was also adopted by employing UV during the electrochemical measurements.

A high-performance Pt-based catalyst for the methanol oxidation reaction: effect of electrodeposition mode and cocatalyst on electrocatalytic activity

“…The remaining peak current density of the p-Pt/CuNi/p-MDAB/ MWCNT catalyst was calculated as 96.2% relative to the initial value, which is higher than that observed for reported catalysts. 72,73 These results suggest that the p-Pt/CuNi/ p-MDAB/MWCNT catalyst possesses excellent stability for the MOR in alkaline media.…”

“…Based on our previous research, NiCu nanostructures with a large surface area were chosen to function as an excellent carrier to support Pt nanoparticles, to gain high catalytic performance. 13,15,16 Different earth-abundant transition metals in combination with Pt nanoparticles have been recently studied for the MOR, e.g., Pt/F-Cu/ CuO, 12 Pt 1 Cu 0.25 ANCs/MWCNTs, 17 Pt NDs/Fe-N-S-GR, 18 PtCuFe alloy, 19 CuWPt nanoalloys, 20 PtNi NCs@HCS(COS), 21 Pt-NiCu/ rGO, 22 PtNiCu nanostructures, 23 Pt-Sn/rGO-GCN, 24 Pt@SnO 2 / G-PR, 25 Pt 3 Mn CNCs, 26 etc. Among the various transition-metal cocatalysts, Ni is considered to be a promising alternative due to its good surface oxidation properties, affordable price, and abundance in the earth.…”

Morphological tuning engineering of Pt@TiO2/graphene catalysts with optimal active surfaces of support for boosting catalytic performance for methanol oxidation

“…Such a negative shift indicates that the downshift in the d-band center of UV-Pt@TiO 2 /graphene is due to the metal–support synergy between Pt and TiO 2 /graphene, suggesting a decrease in the oxygen affinity in the synthesized ternary catalysts, which would further promote the escape of poisoning CO from the active sites and boost the electrocatalytic performance. 37,45,46…”

“…The continuous uniform light illumination and the generation of a high local temperature at the absorption site of the supports lead to the effective improvement of the metal ion reduction rate and homogeneous nucleation, and the reduced catalytic particles are more easily immobilized on the surface of the support. 15,37 Integrating the above superior features, the design and fabrication of Pt–TiO 2 –graphene hybrid materials in combination with optimal exposure of facets of morphology-controlled TiO 2 is expected to achieve excellent performance and bring promising developments for the electrocatalytic MOR.…”

PtIr Alloy Nanoparticles Anchored on CoSe–NC Nanospheres for Efficient Methanol Oxidation

“…To further increase the catalytic efficiency, the introduction of an appropriate support or promoter is very essential for the novel catalyst system development. , Recently, the synergistic effect was discovered on some novel oxophilic components, like metal phosphide and selenide, with the noble metal nanoparticles, which thus largely improves the catalytic performance for MOR . For instance, the catalytic performance for MOR was largely improved for the catalysts of PtRu@FeP because of the effective ligand effects and electronic effects between the PtRu shell and FeP core, and the CoSe 2 -induced electron-enriched Pt surface facilitated the removal of CO intermediates and exhibited enhanced catalytic activity and durability for MOR .…”