Flow Reactor for Sustainable Electrosynthesis Fabricated via Cost-Effective Electroplating and Adhesive Bonding

The use of precious metal electrodes, although capable of improving reaction efficiency, inevitably increases the fabrication cost of electrochemical flow reactors. Additionally, the commonly employed mechanical fastening method consistently poses a risk of leakage. Herein, a low-cost method for fabricating leak-proof electrochemical flow reactors that can withstand high internal pressures is reported using electroplating and chemical bonding methods. By selectively electroplating Pt only on the electrode portion where the electrochemical reaction occurs, the Pt usage on the electrode is reduced by up to 99.4% (selective electroplating of 5-μm-thick Pt = 0.077 g vs. 0.2-mm-thick sheet of Pt = 13.8 g). The reactor shows no liquid leakage, even at a high pressure of 320 psi, and is composed of materials with excellent chemical resistance; therefore, various organic solvents and compounds can be used without restriction. Additionally, the reactor performance is verified by confirming a high yield of up to 88% in the CH/SH cross-coupling reaction. Compared with that of conventional mechanical fastening methods, the fabrication cost is reduced by 97.4%. In addition, this process enables easy fabrication of a reactor of any shape. These findings may increase interest in electrochemical flow synthesis and lead to the industrial application of this approach.