Controlled synthesis of Pt nanoparticles via seeding growth and their shape-dependent catalytic activity

► Size- and shape-controlled Pt nanoparticles are prepared through a seeding growth. ► The growth direction of Pt nanoparticles has strong dependence on the ratio between the amount of Pt precursor and the total surface area of seeds. ► The catalytic ability of prepared Pt nanoparticles is shape-dependent.