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Corneal crosslinking (CXL) can halt the progression of keratoconus. The development of accelerated corneal crosslinking (A-CXL) protocols to shorten the treatment time has been hampered by the rapid depletion of stromal oxygen when higher UVA intensities are used, resulting in a reduced cross-linking effect. It is therefore imperative to develop better methods to increase the oxygen concentration within the corneal stroma during the A-CXL process. Photocatalytic oxygen-generating nanomaterials are promising candidates to solve the hypoxia problem during A-CXL. Biocompatible graphitic carbon nitride (g-C<jats:sub>3<\/jats:sub>N<jats:sub>4<\/jats:sub>) quantum dots (QDs)-based oxygen self-sufficient platforms including g-C<jats:sub>3<\/jats:sub>N<jats:sub>4<\/jats:sub>QDs and riboflavin\/g-C<jats:sub>3<\/jats:sub>N<jats:sub>4<\/jats:sub>QDs composites (RF@g-C<jats:sub>3<\/jats:sub>N<jats:sub>4<\/jats:sub>QDs) have been developed in this study. Both display excellent photocatalytic oxygen generation ability, high reactive oxygen species (ROS) yield, and excellent biosafety. More importantly, the A-CXL effect of the g-C<jats:sub>3<\/jats:sub>N<jats:sub>4<\/jats:sub>QDs or RF@g-C<jats:sub>3<\/jats:sub>N<jats:sub>4<\/jats:sub>QDs composite on male New Zealand white rabbits is better than that of the riboflavin\u00a05\u2019-phosphate sodium\u00a0(RF) A-CXL protocol under the same conditions, indicating excellent strengthening of the cornea after A-CXL treatments. 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