A facile strategy has been developed for the synthesis of H-TS-Au microspheres (MCs) with double shelled hollow architecture and sub-5 nm Au nanoparticles (Au NPs). The synthetic procedure involves the successive sol-gel template-assisted method for the preparation of uniform hierarchical hollow in-hollow H-TS MCs with TiO2/mSiO(2) as yolks/shells, and the unique deposition-precipitation method mediated with Au(en)(2)Cl-3 precursors for the in-situ construction of extremely stable Au NPs under a low temperature hydrogen reduction. The synthesized H-TS-Au MCs were characterized by TEM, SEM, FTIR, XRD, BET and UV-vis absorption spectra. Catalytic activity of H-TS-Au was evaluated using the reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) by NaBH4. Results established that H-TS-Au MCs possessed a large-size double-shelled architecture with high structural integrity and robustness,which can effectively confine numerous tiny Au NPs and restrict them from sintering aggregation even up to further calcination at 800 degrees C. Owing to the advantageous structural configuration and the synergistic effect of TiO2/mSiO(2) double shells, the H-TS-Au MCs were demonstrated to exhibit a remarkable catalytic activity and stability, and preserve the intact morphology after 6 repeating reduction of 4-NP. (C) 2016 Elsevier B.V. All rights reserved.