Oxygen-generating microspheres controlled release by silk protein

•A microsphere as controllable oxygen generator was prepared successfully.•The core–shell microsphere exhibited controllable release of oxygen behavior.•Silk fibroin coating acted an affectively regulator for oxygen generator. In this study, we prepared a microsphere as controllable oxygen generator coated with silk fibroin using poly [lactic-co-(glycolic acid)] as the shell layer and hydrogen peroxide (H2O2) as the core layer, which provides a reliable strategy for the preparation of oxygen-releasing materials for medical or non-medical applications.