N-Doping Holey Graphene TiO₂–Pt Composite as Efficient Electrocatalyst for Methanol Oxidation

Abstract

The nitrogen-doped holey graphene oxide/TiO 2 (TiO 2 −NHGO) composite is synthesized as catalyst support for the Pt catalyst. The resulting catalyst, Pt−TiO 2 −rNHGO, shows higher activity and stability for methanol electrooxidation than the Pt−rGO, Pt−rHGO, and Pt−rNHGO catalysts. The enhancement is because of the combinatory effect of nanoholes in the graphene plane which provide more active sites and efficient mass transport, well-distributed N-doping, and the uniform distribution of TiO 2 NPs on NHGO nanosheets which facilitate to form more uniformly dispersed Pt NPs. In addition, the strong interactions among Pt, TiO 2 , and NHGO also contribute to enhance the performance of catalyst for methanol oxidation.

Nitrogen-Doped Graphene Aerogel Microspheres Used as Electrocatalyst Supports for Methanol Oxidation

“…The above results suggest that micron-sized rGNAMs-III can significantly enhance the number of reaction sites of the catalyst and improve the catalytic efficiency of Pt owing to the uniform loading of Pt NPs and the smaller particle size of Pt NPs. Importantly, in a relative comparison with Pt NPs on carbon-based 3D graphene and 3D nitrogen-doped graphene supports reported in some recent literature syudies ,,− (Figure l), Pt/rGNAMs-III reported in this study possesses a higher mass activity for the MOR. Based on the systematic studies and analysis, it can be reasonably predicted that the optimized Pt/rGNAMs are very suitable for use as methanol oxidation catalysts owing to the unique structural features.…”

Electro‐Catalytic Oxidation of Methanol Catalyzed by Facet‐Controlled Pt‐WC Nanoparticles on In Situ Synthesized Carbon Nanotubes

“…At present, the research on improving the catalytic performance of Pt by conventional methods, such as adjusting catalyst structure [13–16] or introducing synergistic components [17–20] , has been very detailed. Subsequently, the study of Pt‐based catalysts is focused on facilitating the exposure of the highly active crystal facets on the surfaces of catalysts [21] .…”

Synthesis of Different Pt‐ZnO Binary Composites for Synergistic Photo‐Electrocatalytic Oxidation of Methanol in Alkali

“…[1,2] Recently, traditional noble metal Pt hybridized with semiconductor (SC) oxides is recognized as anode electro catalysts for the improvement of kinetics of fuel cell reactions, photo (electro) catalysis, hydrogen production, and photovoltaic devices. [3][4][5] Semiconductor oxides, such as TiO 2 , [6][7][8] NiO, [9,10] Cu 2 O, [11] WO 3 , [12] and ZnO [13] are used frequently as Pt supports because of their excellent physicochemical behaviour, chemical and thermal stability, fascinating electronic and electrochemical activity, strong support/metal interactions and co-catalytic activity. [14,15] Semiconductor metal oxide easily produces MÀ OH which reacts with PtÀ CO by bi-functional mechanism to form CO 2 .…”

“…[8,17] Among the photoexcited semiconducting metal oxides, TiO 2 was extensively researched as a Pt support in the electrocatalytic oxidation of methanol. [7,8,18,19] ZnO, a suitable alternate to TiO 2 , most promising, II-VI type semiconductor, has not been explored in comparison to TiO 2 in MOR. It is cost effective, abundant, non-toxic and chemically stable and has large value of electrochemical coupling coefficient, electron mobility (115-155 cm 2 V À 1 s À 1 ) and exciton binding energy (60 meV) at room temperature.…”

“…Thus synergistic behaviour is expected under light illumination [8,17] . Among the photoexcited semiconducting metal oxides, TiO 2 was extensively researched as a Pt support in the electrocatalytic oxidation of methanol [7,8,18,19] . ZnO, a suitable alternate to TiO 2 , most promising, II‐VI type semiconductor, has not been explored in comparison to TiO 2 in MOR.…”