Executive Summary : | Molybdenum carbide (MoxC) is an excellent electrocatalyst for hydrogen evolution reaction (HER) due to its Pt-like d-band electronic structures and high electrical conductivity. However, there is less effort to realize its oxygen evolution reaction (OER) electrocatalysis due to its sluggish kinetics and high overpotential, which poses a serious concern for MoxC's stability. Transition metals and their compounds, such as oxide, phosphide, nitride, sulfide, and selenide, have gained attention for electrochemical OER applications due to their excellent catalytic activity, abundance, and low cost. However, these electrocatalysts suffer from low catalytic activity, low specific surface area, and pore volume. This study proposes the construction of three-dimensional (3D) hierarchical and porous heteronanostructures of MoxC incorporated with transition metal(s) and their compounds, such as oxide, nitride, phosphide, sulfide, and selenide. The components in these heteronanostructures are intimately connected, allowing for manipulation of electronic structures due to electronegativity differences between Mo and the incorporated metal. The 3D architecture of the electrocatalysts provides electron transfer pathways in three directions (X, Y, and Z), and the proposed electrocatalysts are expected to possess high specific surface area and well-defined pores. The main hypothesis is to construct these heteronanostructures by incorporating transition metal(s) ions in Mo-polydopamine complex, followed by carbonization or compound formation if necessary. The heteronanostructures are anticipated to have ultra-high OER activity, making them inexpensive electrocatalysts for water electrolysis commercialization. |