Mechanism insights for efficient photocatalytic reforming of formic acid with tunable selectivity: Accelerated charges separation and spatially separated active sites

• Published in: Applied catalysis. B, Environmental Environmental, 2023-12, Vol.338, p.123073, Article 123073
• Main Authors: Ye, Xiaoyuan, Dong, Yuchen, Zhang, Ziying, Zeng, Wengao, Zhang, Tuo, Liu, Feng, Guan, Xiangjiu, Guo, Liejin
• Format: Article
• Language: English
• Subjects: Formic acid reforming; Hydrogen; Photocatalysis; Syngas; Tunable selectivity
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2023.123073

Photocatalytic reforming of formic acid (FA) is considered a promising energy conversion method for producing solar fuels and valuable chemical feedstocks to achieve the carbon-neutral goal. However, the application of FA photocatalytic reforming has been restricted by the low efficiency and relatively fixed selectivity due to limited knowledge about the reaction mechanism. Herein, we study the efficient CdS/W2N3 photocatalyst system for photoreforming of FA with tunable selectivity to realize the conversion of products from H2 to syngas under simulated sunlight. Widely tunable CO:H2 ratios between 0 and 2.18 along with a record-high apparent quantum yield (AQY) of 61.00% (H2) and 76.84% (syngas) at 420 nm have been demonstrated. Both theoretical investigation and experimental results show that intrinsic N vacancies and spatially separated active sites are vital factors in achieving tunable selectivity. This work provides a insightful information to construct and understand the photocatalytic system for efficiently reforming of FA with tunable selectivity. [Display omitted] •1D CdS/2D W2N3 photocatalytic system was developed for formic acid reforming.•Spatially separated active sites promised tunable selectivity on H2 and syngas.•The system showed high quantum yield (AQY) for H2 (61.00%) and syngas (71.84%).