Redox-active doped polypyrrole microspheres induced by phosphomolybdic acid as supercapacitor electrode materials

•Redox-active polypyrrole microspheres are prepared by in situ chemical method.•The diameter of the microspheres can be controlled in the range of 100-120 nm.•Phosphomolybdic acid played multi-functional roles for the polymerization of PPy.•PMT-2 co-doped with PMo12 and TSA provided a high specific capacitance of 400F/g.