Photovoltaic powered solar hydrogen production coupled with waste SO2 valorization enabled by MoP electrocatalysts

• Published in: Applied catalysis. B, Environmental Vol. 305; p. 121045
• Main Authors: Park, Jaemin, Yoon, Hyunseok, Lee, Dong-Yeop, Ji, Su Geun, Yang, Wooseok, Tilley, S. David, Sung, Myeong-Chang, Park, Ik Jae, Tan, Jeiwan, Lee, Hyungsoo, Kim, Jin Young, Kim, Dong-Wan, Moon, Jooho
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.05.2022; Elsevier BV
• Subjects: Catalysts; Chemical industry; Electrocatalysts; Gas separation; Hydrogen production; Molybdenum; Molybdenum phosphide; Oxidation; Oxygen evolution reactions; Perovskites; Phosphides; Photoelectric effect; Photoelectric emission; Photovoltaic cells; Photovoltaics; Solar energy; Solar hydrogen; Sulfite; Sulfite oxidation reaction; Sulfur dioxide; Tandem photovoltaics; Water splitting; Solar hydrogen; Sulfite oxidation reaction; Water splitting; Molybdenum phosphide; Tandem photovoltaics
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2021.121045

In this study, we demonstrated high-rate H2 generation by coupling with the sulfite oxidation reaction (SOR) as an alternative to the oxygen evolution reaction for solar H2 production. The emerging and cost-effective molybdenum phosphide electrocatalyst was appropriately optimized and used as a bifunctional catalyst in an alkaline electrolyte for both SOR and HER. Powered by state-of-the-art perovskite–Si tandem photovoltaics, a remarkable photocurrent density of over 17 mA cm−2 was achieved in the HER coupled with the SOR. In addition to the significantly enhanced photocurrent, the SOR can further reduce the overall cost of solar H2 production owing to the elimination of the expensive membranes required for H2 and O2 gas separation. Considering the high global demand for desulfurization via the SOR, the strategy proposed here will enable practical H2 production from renewable sources while effectively converting the toxic SO2 gas into a value-added product for the chemical industry. Solar hydrogen production system employing SOR as alternative anodic reaction is presented. Photoassisted electrochemical device consists of MoP-based catalysts and perovskite–Si tandem PV. Our system based on SOR demonstrates remarkable hydrogen generation photocurrent density of over 17 mA cm–2 under 1-sun illumination with prolonged durability of 50 h. [Display omitted] •Solar H2 production employing SOR as an alternative anodic reaction is presented.•SOR enables the reduction in thermodynamic barrier for H2 production.•Bifunctional MoP-based catalysts for SOR–HER is developed.•SOR-based PV-EC exhibits photocurrent of 17.23 mA cm–2 with durability of 50 h.