Synthesis and functionalization of electrocatalysts and electrocatalytic layers for PEM electrochemical systems using magnetron-ion technologies

摘要

Nanostructured electrocatalysts and catalytic layers for proton-exchange membrane (PEM) electrochemical systems have been synthesized by magnetron-ion sputtering of platinum on the carbon carrier, titanium foil and gas diffusion layers at a direct current. Vulcan XC-72, carbon nanotubes and nanofibres were used as carriers. Platinum metals deposition have been provided onto the initial, chemically processed or metallized carrier. The received mono and bi-metallic catalysts were investigated by electron microscopy, X-ray phase analysis, EXAFS and cyclic voltammetry. The electrodes prepared on the basis of the most efficient synthesized electrocatalysts and catalytic layers were tested in PEM water electrolyzer and fuel cell (FC). Results showed that samples of electrocatalysts possess high degree of chemical purity, high specific active surface (up to 45 m~2/g) and active particles in size ca. 3-5 nanometers. Formation of core-shell structures have been detected for some samples. PEMFC with magnetron sputtered catalytic layers (Pt load of 0.7 mg·cm~(-2)) has showed a power density of 320 mW·cm~(-2). It was shown that magnetron sputtering is efficient process for synthesis of high-quality nanostructured electrocatalysts on the basis of platinum group metals on the carbon carrier and their functionalization.