Exfoliated Boron Nitride (e-BN) Tailored Exfoliated Graphitic Carbon Nitride (e-CN): An Improved Visible Light Mediated Photocatalytic Approach towards TCH Degradation and H2 Evolution.

A series of 2D/2D exfoliated boron nitride/exfoliated g-C3N4 nanocomposites denoted as e-BN/e-CN have been successfully prepared using a simple in situ technique. The successful deposition of e-BN on e-CN was confirmed from high-resolution transmission electron microscopy analysis. According to electrochemical measurements, 1.5 wt % e-BN/e-CN nanocomposites showed 1.5 times more photocurrent than e-CN, which indicates the successful formation of an e-BN/e-CN heterostructure. The photocatalytic activities of the e-CN and e-BN/e-CN composites were investigated through photocatalytic tetracycline hydrochloride (TCH) degradation and H2 evolution under visible light illumination. The 1.5 wt % e-BN/e-CN composite demonstrated the highest photocatalytic activities, which are about 21 and 1.5 fold greater than e-CN towards H2 generation with an apparent conversion efficiency of 2.34% and TCH degradation, respectively. The improved photocatalytic activities of e-BN/e-CN photocatalysts were ascribed to the augmented light-harvesting ability and enhanced separation efficiency of charge carriers. Lower photoluminescence intensity and a smaller arc value in the impedance spectra again proved the reduced recombination of the e--h+ pairs in the e-BN/e-CN nanocomposites. Trapping experiments show that •O2-, h+, and •OH radicals are the predominant reactive species that accelerated the photocatalytic activities of e-BN/e-CN composites. This study opens up a new window towards the fabrication of such 2D/2D nanocomposites in the field of photocatalysis.

Resurrection of boron nitride in p-n type-II boron nitride/B-doped-g-C3N4 nanocomposite during solid-state Z-scheme charge transfer path for the degradation of tetracycline hydrochloride.

Antibiotic contaminants have received much attention due to the increasing serious environmental concerns. In this work, for the first time, we have fabricated a series of significant type-II p-n heterostructure with Z-scheme charge transfer between p-type B-doped g-C3N4 with different proportion of n-type BN through a simple in-situ growth process. PXRD, FTIR, UV-Vis, FESEM, HRTEM and EIS analysis were applied for the detailed characterization of the as-prepared composites to study the crystal phase, structural features, optical and electrical properties. The photocatalytic behaviour of BN/BCN photocatalyst was investigated by the degradation of tetracycline hydrochloride under solar light illumination. Experimental results revealed that about 88.1% of TCH was degraded by the BN/BCN composite containing 4 wt% BN in the BN/BCN matrix, in 60 min of solar light irradiation. Reduction in recombination rate of photo generated electron-hole pair's and enhanced visible light absorption ability is credited to the enhanced photocatalytic performance of BN/BCN composite. Trapping experiment for the scavenging agents has confirmed that superoxide (O2¯) and hydroxyl (OH) radicals are the main reactive species during the TCH degradation process. The high stability shown by the BN/BCN composite opens a new path for designing of significant BN based Z-scheme photocatalyst for prevention of environmental issues.