Mesoporous cobalt phosphate electrocatalyst prepared using liquid crystal template for methanol oxidation reaction in alkaline solution

Abstract

A crystalline mesoporous cobalt phosphate (meso-CoPi) electrocatalyst is prepared using liquid crystal template of non-ionic surfactant of Brij®78. The physicochemical investigations of the electrocatalyst executed by surface area analyzer, XRD, transmission electron microscope submits creation of a mesoporous crystalline nanostructured of meso-CoPi with a surface area of 124 m2 g−1. This is an 10-fold greatness superior than that for bulk-CoPi particles produced without surfactant template. The meso-CoPi electrocatalyst comprises of metallic cobalt layered with a cobalt-oxo/hydroxo-phosphate layer which facilitates the electro-oxidation of methanol at modest overpotential of < 1.2 V vs RHE in alkaline solution. The methanol oxidation activity of the meso-CoPi catalyst shows more than 20-fold current increase at 1.4 VRHE in comparison to bulk-CoPi counterpart which due to the enhancement of the electroactive specific surface area. Liquid crystal template chemical approach provides a reproducible stage to synthesize mesoporous metal phosphates with improved electrocatalytic activities. Keywords: Mesoporous, Crystal template method, Methanol, Electrocatalysts, Cobalt phosphate