Electron-poor copper nanoparticles over amorphous zirconia-silica as all-in-one catalytic sites for the methanol steam reforming

•Si addition inhibits zirconia crystallization.•Si addition to zirconia prevents Cu nanoparticles overgrowth upon reduction.•Metallic Cu nanoparticles in 2–3 nm size range feature electron-poor surface.•Methanol adsorption, dehydrogenation, and H2 formation occur on electron-poor Cu nanoparticles.•High H2 productivity achieved without addition of La or Y.