Hydrothermally engineered aluminium doped Mn3O4-rGO heterostructure with superior electrocatalytic activity for HER

초록

The production of inexpensive and effective nanomaterials for electrochemical water splitting utilizing non-noble metal oxides is a viable approach to advance clean energy and address environmental challenges. The doping and composite formation can markedly enhance the electrochemical performance of materials by minimizing nanoparticle aggregation and improving cycling stability. This study involves the synthesis of aluminium (Al) doped Mn3O4-rGO composite by a hydrothermal technique. The physical analysis demonstrated a robust interface between rGO nanosheets and Al doped Mn3O4, functioning as electron transport pathways that improve efficacy in hydrogen evolution reaction (HER). The electrochemical assessment of prepared samples was examined in basic medium. The Al doped Mn3O4-rGO composite demonstrated outstanding electrocatalytic efficiency, attaining a minimum overpotential (eta = 128 mV) at 10 mA/cm2 current density (j) with less Tafel slope (45.8 mV/dec). The double layer capacitance (Cdl) of Al doped Mn3O4-rGO composite (8.5 mF/cm2) was more than that of other materials, signifying a favorable ECSA (electrochemically active surface area) of 212.5 cm2. Moreover, Al-doped Mn3O4-rGO composite enhanced stability of about 50 h during prolonged HER assessments. Thus, Al doped Mn3O4-rGO composite presents a feasible substitute to noble metal-based catalysts demonstrating superior efficiency in energy conversion applications.

키워드