The integration of superacid-like heteropolyacids offers a promising route to develop highly proton-conducting membranes for energy storage and conversion. However, the inherent hydrophilicity of these acids can cause leaching, which undermines the fuel cell performance. In our research, we engineered a proton-conductive membrane with a facile hydrothermal synthesis approach to form stabilized hybrid superacids, namely, phosphotungstic acid (PTA), with graphitic carbon nitride (PCN) and its incorporation in a short-side-chain ionomer, namely, Aquivion. This unique approach via PCN nanohybrids enhances the proton transport within the membrane. These nanohybrids effectively combined the strong acidity of PTA with continuous 2D proton-transport pathways via a short side chain, resulting in a notable proton conductivity of 0.228 S cm