visible-light-responsive bismuth oxybromide/graphite-like c3n4 hybrid material and its application in photocatalysis via internal electric field

In this work, we propose a facile route to obtain biobr/ graphite-like c3n4 hybrid material, which was constructed by in situ depositing biobr onto the surface of g-c3n4 as a template via self-assembly procedure at room temperature. this method describes the use of g-c3n4/biobr nanocomposite for the superior photocatalytic performances under visible light excitation (λ > 420 nm). the crystalline phase, morphology, textile structure and components of the samples were studied by several tools such as x-ray diffraction, transmission electron microscopy, n2 adsorption–desorption, energy dispersive x-ray spectrum, fourier transform infrared spectroscopy and raman spectroscopy. the optical, photoelectrochemical properties and band structure were measured by ultraviolet–visible diffuse reflectance spectroscopy, steady-state photoluminescence spectra, photocurrent response analysis, electrochemical impedance spectra and valence-band x-ray photoelectron spectroscopy techniques, respectively. in addition, the catalytic activities of the hetero-structural material were broadly investigated and compared with single biobr or g-c3n4 alone in the same reaction. the as-obtained biobr/g-c3n4 composite showed distinctive advantages over biobr alone and universality for various substrate, i.e., dichloronaphthol degradation and reduction efficiency of cr (vi) over biobr/g-c3n4 was increased by up to 3 and 2.5 times, respectively. the enhanced photocatalytic activity of the as-prepared biobr/g-c3n4 complex was mainly contributed to the effective charge transfer, which can further cause the establishment of the internal electric field in the interface between biobr and g-c3n4 to boost the space charge separation. this work gives a new route for designing high efficient semiconductor hybrid photocatalyst with broad absorption region as well as quick charge separation.