摘要： It is desirable but challenging to design efficient micro-/nanoreactors for chemical reactions. In this study, we fabricated mesoporous double-shelled hollow microreactor composed of N-doped C coated ultiafine In2O3 nanoparticles (N-C/In2O3 HD) by the thermolysis of dodecahedral In-based framworks in Ar atmosphere. The obtained N-C/In2O3 HD exhibited excellent photocatalytic activity toward photocatalytic oxidative hydroxylation of a series of arylboronic acids substrates, due to its enhanced optical absorption and efficient separation of photo-generated electron-hole pairs endowed by the unique structure and uniformly coated N-doped C layers. Furthermore, we found that O2?- was the critical active species in the process of photocatalytic oxidative hydroxylation of arylboronic acids, and the formation mechanism of this radical was also proposed. The theoretical calculation further confirmed the N-doped C layer acted as electron acceptor and revealed the microscopic charge carrier migration path via the In2O3/N-doped graphite interfaces i.e., the photo-generated electrons from hybrid states of In2O3, composed of In 5s and 2p orbitals, transferred into the hybrid states of N-doped graphite, composed of C 2p and N 2p orbitals. The present study may be helpful for understanding and designing carbon-based micro-/nanoreactors for photocatalytic reactions and can be useful for investigating other relevant micro-/nanoractors as well.