TY - JOUR
T1 - Bismuth Silver Oxysulfide for Photoconversion Applications: Structural and Optoelectronic Properties
AU - Baqais, Amal Ali Abdulallh
AU - Curutchet, Antton
AU - Ziani, Ahmed
AU - Ait Ahsaine, Hassan
AU - Sautet, Philippe
AU - Takanabe, Kazuhiro
AU - Le Bahers, Tangui
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: AC and TLB acknowledge the PSMN computation center for providing calculation resources.
PY - 2017/9/18
Y1 - 2017/9/18
N2 - Single-phase bismuth silver oxysulfide, BiAgOS, was prepared by a hydrothermal method. Its structural, morphological and optoelectronic properties were investigated and compared with bismuth copper oxysulfide (BiCuOS). Rietveld refinement of the powder X-ray diffraction (XRD) measurements revealed that the BiAgOS and BiCuOS crystals have the same structure as ZrSiCuAs: the tetragonal space group P4/nmm. X-ray photoelectron spectroscopy (XPS) analyses confirmed that the BiAgOS has a high purity, in contrast with BiCuOS, which tends to have Cu vacancies. The Ag has a monovalent oxidation state, whereas Cu is present in the oxidation states of +1 and +2 in the BiCuOS system. Combined with experimental measurements, density functional theory calculations employing the range-separated hybrid HSE06 exchange-correlation functional with spin-orbit coupling quantitatively elucidated photophysical properties such as ab-sorption coefficients, effective masses and dielectric constants. BiCuOS and BiAgOS were found to have indirect bandgaps of 1.1 and 1.5 eV, respectively. Both possess high dielectric constants and low electron and hole effective masses. Therefore, these materials are expected to have high exciton dissociation capabilities and excellent carrier diffusion properties. This study reveals that BiAgOS is a promising candidate for photoconversion applications.
AB - Single-phase bismuth silver oxysulfide, BiAgOS, was prepared by a hydrothermal method. Its structural, morphological and optoelectronic properties were investigated and compared with bismuth copper oxysulfide (BiCuOS). Rietveld refinement of the powder X-ray diffraction (XRD) measurements revealed that the BiAgOS and BiCuOS crystals have the same structure as ZrSiCuAs: the tetragonal space group P4/nmm. X-ray photoelectron spectroscopy (XPS) analyses confirmed that the BiAgOS has a high purity, in contrast with BiCuOS, which tends to have Cu vacancies. The Ag has a monovalent oxidation state, whereas Cu is present in the oxidation states of +1 and +2 in the BiCuOS system. Combined with experimental measurements, density functional theory calculations employing the range-separated hybrid HSE06 exchange-correlation functional with spin-orbit coupling quantitatively elucidated photophysical properties such as ab-sorption coefficients, effective masses and dielectric constants. BiCuOS and BiAgOS were found to have indirect bandgaps of 1.1 and 1.5 eV, respectively. Both possess high dielectric constants and low electron and hole effective masses. Therefore, these materials are expected to have high exciton dissociation capabilities and excellent carrier diffusion properties. This study reveals that BiAgOS is a promising candidate for photoconversion applications.
UR - http://hdl.handle.net/10754/625512
UR - http://pubs.acs.org/doi/abs/10.1021/acs.chemmater.7b02664
UR - http://www.scopus.com/inward/record.url?scp=85032037908&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.7b02664
DO - 10.1021/acs.chemmater.7b02664
M3 - Article
SN - 0897-4756
VL - 29
SP - 8679
EP - 8689
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 20
ER -