Immobilization of FeFe-hydrogenase on black TiO2 nanotubes as biocathodes for the hydrogen evolution reaction

• DOI: 10.1016/j.elecom.2022.107221
• Publication Date: 2022-01-22T16:26:29Z
• Authors: Xin Liu; Sanne Risbakk; Patricia Almeida ...; Mingyi Yang; Paul Hoff Backe; Magnar Bjørås; Truls Norby; Athanasios Chatzi...
• Keywords: Hydrogenase; Nanomaterials

Hydrogenases are attractive biocatalysts for utilization in electrochemical devices as potential replacement Pt hydrogen evolving electrodes. In this work, we investigate the immobilization of ferredoxin tagged FeFe-hydrogenase (Fd-HydA1) on black TiO2 nanotubes (bTNTs), with uniform nanotube opening diameters 140 nm. By utilizing an immunogold labelling method, show that enzymes attach top surface bTNTs film rather than inner walls, reflecting difficulty to insert into high aspect-ratio nanomaterials O2-shielding. Nevertheless, cyclic voltammetry demonstrates direct electron transfer between Fd-HydA1 and evolution reaction (HER) neutral media. This work provides new insight towards design nanostructured electrodes enzyme immobilization.