We demonstrate a self-sacrifice-templating method to synthesize Pt–Pb hollow-sphere networks, in which the hollow-spheres arise from the self-sacrifice of in situ formed Pb nanoclusters without the use of a pre-existing template and the networks originate from the diffusion-limited aggregation process. Of particular interest is that the as-prepared Pt–Pb catalyst shows a significantly enhanced activity for formic acid electrooxidation.