A tubular electrochemical hydrogen compressor

Electrochemical hydrogen compression is a promising alternative to conventional mechanical compression due to low maintenance costs and high one-stage compression ratios. The typically employed planar systems, however, are intrinsically difficult to operate in high differential pressure environments. Tubular systems are inherently advantageous for high differential pressure systems but require innovative membrane electrode assembly development. This study unveils the first tubular EHC featuring a membrane electrode assembly supported by a stainless steel 3D-printed porous anode. The membrane electrode assembly for gas-phase electrochemistry is produced by spray coating the porous anode with Pt/C as the catalyst and joining the anode with a tubular catalyst-coated membrane. Electrochemical characterization demonstrates the functionality of the tubular EHC at current densities up to 60 mAcm−2 with a cell potential of 200 mV under non-pressurized conditions. Moreover, a pressure difference of 2 bar is achieved at 60 mAcm−2 within the first 60 min in continuous mode. By demonstrating the proof-of-principle for the first tubular EHC, this work paves the way for new research avenues in electrochemical process engineering, offering a broad spectrum of applications, from enhancing EHC technologies to advancing electrochemical CO2 reduction.