Fabrication of C@Mo Ti1−O2−δ nanocrystalline with functionalized interface as efficient and robust PtRu catalyst support for methanol electrooxidation

A core shell structured [email protected]xTi1-xO2-δ nanocrystal with a functionalized interface ([email protected]) was fabricated via the hydrothermal method with subsequent annealing derived from tetrabutyl orthotitanate. The formation of anatase TiO2 was inhibited by the simultaneous presence of the hydrothermal etching/regrowth process, infiltration of Mo dopants and carbon coating, which endows the [email protected] with an ultrafine crystalline architecture that has a Mo-functionalized interface and carbon-coated shell. PtRu nanoparticles (NPs) were supported on [email protected] by employing a microwave-assisted polyol process (MAPP). The obtained PtRu/[email protected] catalyst has 2.68 times higher mass activity towards methanol electrooxidation than that of the un-functionalized catalyst (PtRu/[email protected]) and 1.65 times higher mass activity than that of PtRu/C catalyst with over 25% increase in durability. The improved catalytic performance is due to several aspects including ultrafine crystals of TiO2 with abundant grain boundaries, Mo-functionalized interface with enhanced electron interactions, and core shell architecture with excellent electrical transport properties. This work suggests the potential application of an interface-functionalized crystalline material as a sustainable and clean energy solution.