Nowadays, molybdenum carbides (Mo2C) represent alternative electrocatalysts to noble metal for the hydrogen evolution reaction (HER). Here, a fast and simple process is proposed for the fabrication of Mo2C-based electrocatalysts on a carbon cloth substrate by photonic flash synthesis (PFS) from MoO3/graphene precursor under an ambient atmosphere. SEM, XRD, and XPS results demonstrated the successful thermal decomposition of molybdenum oxides into a porous nanostructure of beta-Mo2C after exposing the precursor material to a 575 V lamp flash for four successive pulses. As a result, the as-prepared Mo2C@575 V-4p demonstrates a Tafel slope of 63 mV.dec(-1) and a low overpotential of similar to 160 and similar to 230 mV to drive 10 and 50 mA.cm(-2) in acidic media, respectively. Furthermore, high catalytic stability was observed, validating further the strategy for efficient and reliable catalytic material preparation.