Affiliation:
1. Department of Solid State Engineering University of Chemistry and Technology Technicka 5 Prague 166 28 Czech Republic
2. Faculty of Mathematics and Physics Department of Surface and Plasma Science Charles University V Holešovičkách 2 Prague 8 180 00 Czech Republic
3. Faculty of Science J. E. Purkyne University in Usti nad Labem Ceske Mladeze 8 Usti nad Labem 400 96 Czech Republic
4. Department of Physics and Measurements University of Chemistry and Technology Prague 16628 Czech Republic
Abstract
AbstractA heterojunction photo‐electrode(s) consisting of porous black titanium oxide (bTiO2) and electrochemically self‐activated TaS2 flakes is proposed and utilized for hydrogen evolution reaction (HER). The self‐activated TaS2 flakes provide abundant catalytic sites for HER and the porous bTiO2, prepared by electrochemical anodization and subsequent reduction serves as an efficient light absorber, providing electrons for HER. Additionally, Au nanostructures are introduced between bTiO2 and TaS2 to facilitate the charge transfer and plasmon‐triggering ability of the structure created. After structure optimization, high HER catalytic activity at acidic pH and excellent HER activity at neutral pH are achieved at high current densities. In particular, with the utilization of bTiO2@TaS2 photoelectrode (neutral electrolyte, sunlight illumination) current densities of 250 and 500 mA cm−2 are achieved at overpotentials of 433, and 689 mV, respectively, both exceeding the “benchmark” Pt. The addition of gold nanostructures further reduces the overpotential to 360 and 543 mV at 250 and 500 mA cm−2, respectively. The stability of the prepared electrodes is investigated and found to be satisfying within 24 h of performance at high current densities. The proposed system offers an excellent potential alternative to Pt for the development of green hydrogen production on an industrial scale.