Novel hydrogen-doped SrSnO3 perovskite with excellent optoelectronic properties as a potential photocatalyst for water splitting
Document Type
Article
Publication Date
5-15-2022
Abstract
Developing and designing novel electrodes for photocatalytic water splitting using computational analysis has become a crucial interest recently through bulk and surface calculations of the investigated materials. Doping wide band gap metal oxides has proven to be an efficient method for optical properties enhancement and band gap engineering. Herein, first-principles calculations were employed to investigate the possibility to engineer the optical and structural properties of SrSnO3 perovskite as a potential catalyst for photo-driven hydrogen production. Specifically, the synergistic effect of hydrogen doping and oxygen vacancies (OV) on the optoelectronic properties of SrSnO3 was for the first time investigated and discussed in detail. The interstitial hydrogen defects (Hi) are energetically favorable compared with the substitutional hydrogen defects. Mono- and co-hydrogen occupied oxygen vacancies sites were further examined. Interstitial hydrogen doping was found to introduce a shallow defect state below the conduction band minimum (CBM) forming a band tailing and increasing the dielectric constant. Thus, it could be used in gate dielectric applications. The created defect states upon doping were found to depend directly on the defect site and the defect concentration. At high concentration of oxygen vacancies defect, the HOV-OV structural configuration showed localized and shallow defect states with a band gap of 1.3 eV below the CBM. It also considerably increased the dielectric constant with optical absorption enhancement, compared to the pristine SrSnO3 counterpart. With optimum Gibbs free energy of hydrogen evolution reaction (HER) and theoretical band gap straddling of the oxygen and hydrogen evolution potentials, low exciton binding energy, and high permittivity, the HOV-OV structure is an ideal novel candidate catalyst for photocatalytic water splitting.
Recommended Citation
Salim, Fatma; Ahmed, Mohamed; Sadek, Mohamed; and Elmahgary, Maryam Galal, "Novel hydrogen-doped SrSnO3 perovskite with excellent optoelectronic properties as a potential photocatalyst for water splitting" (2022). Chemical Engineering. 268.
https://buescholar.bue.edu.eg/chem_eng/268
