Robust and highly conductive Ti4O7/MXene nanocomposites as high-performance and long cyclic stability oxygen reduction electrocatalysts

Electrocatalysts play an important role in the cathodic Oxygen Reduction Reaction (ORR) of fuel cells. Because of the high cost, poor cycle stability and methanol tolerance, the commercial Pt/C catalysts have been seriously restricted during large-scale application and development in electrochemical devices. The development of non-noble metal ORR catalysts is one of the effective ways to achieve fuel cell cost reduction and performance improvement at the same time. In this work, Ti 4 O 7 /MXene nanocomposites were synthesized through hydrothermal followed by carbothermal reduction reactions. Such catalysts exhibit large electrochemical active surface area (ECSA = 215.74 cm 2 ) and excellent ORR catalytic activity in alkaline media. The initial potential and half-wave potential were confirmed to be 0.91 V and 0.72 V with the electron transfer number of 3.3. In addition, the Ti 4 O 7 /MXene catalysts have better cyclic stability and methanol tolerance than commercial Pt/C catalyst. This study provides a new idea and method for the innovative preparation of MXene-based composite electrocatalysts.