The reactive metal-support interaction (RMSI) offers electronic, geometric and compositional effects that can be used to tune catalytic active sites. Generally, supports other than oxides are disregarded as candidates for RMSI. In this presentation, we will discuss an example of non-oxide based RMSI between Pt and Nb2CTx MXene, a recently developed, two-dimensional (2D) metal carbide. The surface functional groups of the 2D carbide can be reduced, and a Pt-Nb surface alloy is formed at a moderate temperature (350 °C). Such an alloy exhibits weaker CO adsorption than monometallic Pt. Water-gas shift (WGS) reaction kinetics reveal that the RMSI stabilizes the nanoparticles and creates alloy-MXene interfaces with higher H2O activation ability compared to a non-reducible support or a bulk niobium carbide. This RMSI between Pt and the niobium MXene support can be extended to other members of the MXene family and opens new avenues for the facile design and manipulation of functional bimetallic catalysts.