Hydrogen proton exchange membrane fuel cells have emerged as a promising sustainable energy technology offering low emissions and high fuel efficiency. However, one of the challenges limiting their use is fuel crossover, which leads to decreased fuel efficiency and durability of the fuel cell. Two-dimensional germanane was investigated as a diffusion barrier to reduce hydrogen crossover, while maintaining proton conductivity. Layers of GeH were spray-coated onto Nafion membranes (NR211) with thicknesses ranging from 40 nm to 120 nm and used in fuel cell tests with the GeH-side facing the anode. GeH decreased hydrogen crossover by up to 21% without significantly reducing proton conductivity. Additionally, GeH-coated membranes exhibited significantly better durability in accelerated stress tests compared to bare NR211 membranes.