Gold (Au) nanocatalysis has spurred much interest in chemical reactions under mild conditions. Here we report on the superior reactivity of silica hosting Au (Au@SiO2) nanocatalyst for direct synthesis of H2O2 in a semi-batch reactor under ambient conditions. The nanocatalyst with rattle nano-architecture is composed of a uniformly sized Au core, a silica sphere, and silica shell. Direct synthesis of H2O2 from H-2 and O-2 is an ideal but challenging process for replacing the commercial route of anthraquinone process. The unique rattle structure facilitates the formation of hydroperoxo species on total surface area of the sample was calculated based H2O2 formation. The turnover frequency (TOF) of H2O2 formation was 2-3 orders of magnitude higher than that of other Au catalysts. The finding in this work offers a new strategy for the design of Au nanocatalysts, which would lead to improvement in their catalytic performance for other reactions. (C) 2014 Elsevier B.V. All rights reserved.