One‐Step Fabrication of Ultralow Pt Loading High Efficiency Proton Exchange Membrane for Water Electrolysis by Conventional E‐Beam Metal Deposition

Abstract

AbstractProton exchange membrane water electrolysis (PEMWE) is known as an effective and environmental‐friendly method for hydrogen production. However, the process is hindered by the necessity of large loading of high‐priced noble metals in the conventional approaches. To resolve this problem, a highly efficient Nafion‐based catalyst and proton exchange system are developed, which only need ultralow platinum loading by direct e‐beam evaporation deposition. Scanning electron microscopy is performed before and after the deposition, which reveals a very smooth morphology. By assembling the PEMWE device with above‐mentioned cathode and conventional iridium black anode, the current density reaches 500 mA cm−2 with a platinum loading of only 0.00379 mg cm−2 at 1.64 V under 80 °C. A mass activity of ≈132 A mg−1 is achieved, which is one order of magnitude higher than previously reported results. Moreover, powered by a commercial silicon solar cell, it realizes a solar‐to‐hydrogen conversion efficiency up to 8.26%. This work opens up an avenue of fabricating PEMWE with an ultralow catalyst loading, which may have enormous potential for future industrial scale applications.