A new generation of double dielectric barrier discharge (DDBD) reactor featured by a metal powder (MP) high voltage electrode is presented. The MP high voltage electrode not only has excellent homogeneous discharge performance but also has the advantage of without regular maintenance. Therefore, the MP-DDBD reactor was proved to be suitable for the uninterrupted and safe synthesis of high purity H2O2 aqueous solution with up to 65 wt % concentration from the H2/O2 mixture. The scale-up synthesis of H2O2 was successfully attempted in an integrated device based on the MP-DDBD reactor. The future practical H2O2 synthesizer based on the MP-DDBD reactor will be small and movable, and therefore, be convenient to supply high purity H2O2 on site for small scale users like semiconductor industry. © 2013 American Institute of Chemical Engineers AIChE J 60: 415–419, 2014 Additional Supporting Information may be found in the online version of this article. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.