Constructing Cu/BN@PANI ternary heterostructure for efficient photocatalytic hydrogen generation: A combined experimental and DFT studies

摘要

In this report, (PANI) embedded copper NPs with h-BN has been developed as a new high-performance photocatalysts, minimized the use of precious metals, for hydrogen generation. The facile in-situ synthesis of the ternary Cu/BN@PANI nanocomposite via the hydrothermal process is successfully achieved. The photoexcited charge transfers are controlled by creating suitable junction architectures, as such the ternary composite exhibits remarkably enhanced hydrogen generation. The XRD, XPS, and TEM analysis confirms the coexistence of the Cu/BN@PANI nanocomposites' phase and composition. Cu/BN@PANI-2.5 wt% showed a sustained H-2 evolution rate of 3121 mu mol g(-1) h(-1) with quantum efficiency 6.91% and increased photocatalytic current response of 49 mA cm(-2). A higher estimated lifetime in Cu/BN@PANI-2.5 wt% (8.66 ns) suggests enhanced photogenerated charge carrier efficiency across the junction interface within the heterostructures. DFT calculations reveal that the conduction band minimum and valence band maximum of PANI is higher than those of the Cu-7 cluster, indicating desirable band alignment and ensuring high hydrogen evolution reaction activity. The light illuminates on the Cu/BN@PANI composite, the electrons of SP2 type h-BN and pi conjugated PANI photoexcited to the conduction band of Cu NPs and the excited hole of Cu NPs quickly transfers to the valence band of PANI, which is in agreement with the experimental results. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.