Charge modulation at atomic-level through substitutional sulfur doping into atomically thin Bi₂ WO₆ toward promoting photocatalytic CO₂ reduction

• Main Authors: Teh, Yee Wen, Er, Chen-Chen, Kong, Xin Ying, Ng, Boon-Junn, Yong, Siek-Ting, Chai, Siang-Piao
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2022
• Subjects: Science::Chemistry; Density Functional Theory; Nanosheets
• Online Access: https://hdl.handle.net/10356/163084
• Institution: Nanyang Technological University

Photocatalytic reduction of CO2 has attracted enormous interest as a sustainable and renewable source of energy. In the past decade, numerous bulk-type semiconductors have been developed, but the existing designs suffer many limitations, namely rapid recombination of charge carriers and weak light absorption ability. Herein, a bottom-up approach was developed to design atomically thin sulfur-doped Bi2 WO6 perovskite nanosheets (S-BWO) with improved reduction ability, extended visible light absorption, prolonged lifetime of charge carriers, enhanced adsorption of CO2 , and reduced work function. Compared with pristine Bi2 WO6 (P-BWO), S-BWO nanosheets exhibited a 3-fold improvement in photocatalytic reduction of CO2 under simulated sunlight irradiation. Experimental studies and density functional theory calculations revealed the synergistic roles of atomically thin nanosheets and S atoms in promoting photocatalytic efficiency.