Polyetheretherketone microspheres loaded with cerium dioxide nanoparticles mitigate damage from cellular oxidative stress and promote bone repair

•CeO2NPs/PEEK composite microspheres were prepared through the conversion of Ce(SO4)2 to CeO2 by hydrothermal-assisted hydrolysis process.•The CeO2NPs/PEEK microspheres exhibited uniform size and promoted cell adhesion, spreading, proliferation and osteogenic differentiation.•The catalase-like activity of CeO2NPs/PEEK microspheres reduced hydrogen peroxide in the cell micro-environment and promoted bone regeneration in vivo.•The CeO2NPs/PEEK microspheres showed great potential in bone repair as novel functional biomedical materials.