Synergetic effect of Sn addition and oxygen-deficient atmosphere to fabricate active hematite photoelectrodes for light-induced water splitting.

摘要: This work describes the design of a microwave-assisted method using hydrothermal conditions to fabricate pure and Sn-doped hematite photoelectrodes with varied synthesis time additional thermal treatment under air N2 atmosphere. The photoelectrode formed atmosphere, Sn deposited on its surface-which is represented by material synthesized at 4 h -exhibits highest performance. Hence, addition followed high temperature annealing conducted in an oxygen-deficient atmosphere seems create oxygen vacancies, prevent segregation dopant form SnO2 phase crystal surface, reducing energy suppressing grain growth. increased donor number density provided vacancies (confirmed x-ray photoelectron data), possible reduction boundary or interface might favor charge separation, increase electron transfer through into back contact (FTO substrate). In consequence, light-induced water oxidation reaction efficiency Sn-hematite was significantly comparison ones, even though vertical rod morphology not preserved. finding provides novel insight intentional addition, revealing that surface (or boundaries) could-by increasing mobility-be more relevant factor developing active than control columnar morphology.