An active catalyst system for proton reduction composed of a bipyridyl platinum complex and a polymer membrane

Electrocatalysis for the H+ reduction with bis(2,2'-bipyridyl) Pt complex ( Pt(bpy)(2)(2+)) incorporated in a polymer matrix was studied. When the cycl ic voltammogram (CV) was measured at a basal-plane pyrolytic graphite (BPG) electrode coated with a Nafion(R) (Nf) membrane incorporating Pt(bpy)(2)(2 +) (denoted as BPG/Nf[Pt(bpy)(2)(2+)]), a remarkable growth of the cathodic current due to H+ reduction was observed below -0.4 V (vs. Ag/AgCl) in a r epeated scanning. A much higher amount of H-2 was obtained with the system BPG/Nf[Pt(bpy)(2)(2+)] than by the conventional Pt-black. The XPS spectrum of Nf[Pt(bpy)(2)(2+)] showed the formation of zero-valent Pt after the elec tcochsnlicd process, indicating that H+ reduction begins to take place afte r formation of the catalytically active species. This work shows that a hig hly active catalyst system for H+ reduction can be fabricated from a noble metal complex and a polymer matrix.