Ni-Nanoparticles-Bound Boron Nitride Nanosheets Prepared by Radiation-Induced Reduction-Exfoliation Method and Their Catalytic Performance

The efficient exfoliation of hexagonal boron nitride (h-BN) to fabricate boron nitride nanosheet (BNNS) is a challengeable task in the hot field of two-dimensional material preparation. In this paper, a new radiation-induced reduction-exfoliation method is introduced to achieve the one-step exfoliation of h-BN to form Ni nanoparticles (NiNP) bound BNNS (Ni/BNNS) in a binary isopropanol/water medium under gamma-ray radiation at ambient temperature and pressure. The detailed process involves an effective intercalation of Ni2+ ions in the interlayers of h-BN dispersed in isopropanol/water medium and an in-situ growth of NiNP under gamma-ray radiation. Taking advantage of the volume expansion effect generated by the growth of NiNP and the help of cationic surfactants such as hexadecyltrimethylammonium chloride (CTAC), sheet-like Ni/ BNNS with an average thickness of BNNS less than 5 nm and 200 nm square are peeled from h-BN and stably dispersed in water. The prepared magnetic Ni/BNNS exhibits high catalytic performance, excellent structural stability, and reusability in the reduction of 2-nitroaniline (2-NA). After 5 cycles, the conversion of 2-NA still reaches 95.9% within 500 s. More interestingly, when the Ni/BNNS was dispersed into water/methanol solution at a content of 0.17 mg/mL, followed by the exposure under the irradiation of simulated sunlight, H2 evolution of 8404.3 μmol·gNi−1 with 2 h can be detected. This work not only provides a new idea to realize the exfoliation of nano-scaled sheet layer from h-BN, but also opens a new way to one-step prepare two-dimensional-material-supported nano-metal catalyst by taking advantage of gamma-ray radiation.