Highly active platinum supported on Mo-doped titanium nanotubes suboxide (Pt/TNTS-Mo) electrocatalyst for oxygen reduction reaction in PEMFC.

In this study, an innovative carbon-free electrocatalyst for oxygen reduction reaction was synthesized via deposition of platinum on titanium nanotube suboxide (trititanium pentoxide nanotubes, TNTS) obtained from titania doped with molybdenum (Pt/TNTS-Mo). The TNTS-Mo support was synthesized in autoclave, while the Pt/TNTS-Mo using the polyol method. The carbon-free support and the Pt-based catalyst were fully characterized via rotating disk electrode (RDE) technique and polymer exchange membrane fuel cell (PEMFC) station by preparing a membrane electrode assembly (MEA) with Nafion ® 115, loaded with 0.35 mg Pt cm −2 of Pt/TNTS-Mo at the cathode, and 0.35 mg Pt cm −2 of commercial Pt/C (E-TEK) at the anode. In RDE experiments, the Pt/TNTS-Mo exhibited low overpotential and remarkable electroactivity toward oxygen reduction reaction (ORR: mass activity of 110.7 mA mg Pt −1 at 0.9 V vs SHE). Moreover, the Pt/TNTS-Mo demonstrated excellent stability. Tests in a 25 cm 2 single cell PEMFC resulted to maximum power density of 0.52 W cm −2 . [ABSTRACT FROM AUTHOR]