Construction of Frustrated Lewis Pair Sites in CeO₂–C/BiVO₄ for Photoelectrochemical Nitrate Reduction

Abstract

Photoelectrochemical nitrate reduction reaction (PEC NIRR) could convert the harmful pollutant nitrate (NO 3 − ) to high-value-added ammonia (NH 3 ) under mild conditions. However, the catalysts are currently hindered by the low catalytic activity and slow kinetics. Here, we reported a heterostructure composed of CeO 2 and BiVO 4 , and the "frustrated Lewis pairs (FLPs)" concept was introduced for understanding the role of Lewis acids and Lewis bases on PEC NIRR. The electron density difference maps indicated that FLPs were significantly active for the adsorption and activation of NO 3 − . Furthermore, carbon (C) improved the carrier transport ability and kinetics, contributing to the NH 3 yield of 21.81 μg h −1 cm −2 . The conversion process of NO 3 − to NH 3 was tracked by 15 NO 3 − and 14 NO 3 − isotopic labeling. Therefore, this study demonstrated the potential of CeO 2 −C/BiVO 4 for efficient PEC NIRR and provided a unique mechanism for the adsorption and activation of NO 3 − over FLPs.

Nitrate Reduction by NiFe-LDH/CeO2: Understanding the Synergistic Effect between Dual-Metal Sites and Dual Adsorption

“…Cerium dioxide (CeO 2 ) has been confirmed as a sufficient support for the nitrate reduction process due to its stable structure and strong reversible redox ability. Meanwhile, the flexible conversion between Ce 3+ /Ce 4+ accelerates the mobility of internal charges, contributing to a dynamic advantage for the reduction reaction. − Therefore, the integration of NiFe-LDH and CeO 2 could be considered as an efficient approach to establishing a multifunctional structure for both the enrichment and reaction of NO 3 – . However, the EC-NITRR mechanism for NiFe-LDH/CeO 2 has still not been reported, as far as we know.…”

Synergistic High-Efficiency Photoelectrochemical Water Splitting via Type-II Heterojunction MW:BVO/CeO2 Coupled with Ultrathin NiFeOOH

“…In recent years, visible light-driven photocatalysts have attracted significant attention due to their ability to effectively harness solar energy for addressing the challenges of energy scarcity and environmental issues . However, achieving efficient and practical photocatalysts requires the characteristics of visible light absorption and effective separation of photogenerated charge carriers to participate in photocatalytic reactions .…”

Charge Photoaccumulation in Covalent Polymer Networks for Boosting Photocatalytic Nitrate Reduction to Ammonia

“…e) Sample 1 H-NMR spectra showing the signals of15 NH 3 (upper) and14 NH 3 (lower) produced by feeding the system with 15 NO 3 − and 14 NO 3 − , respectively. f) A radar plot comparison of different PEC NO 3 − reduction systems between our system and literaturereported photosystems [25][26][27][28][29]. g,h) Photocurrent responses of HrHE-CA-Cu showing the influences of NO 3 − concentration (g) and photoelectrode layer (h).…”