Evidence of direct Z-scheme triazine-based g-C₃N₄/BiOI (001) heterostructures: a hybrid density functional investigation

Abstract

In this work, we systematically investigate the photocatalytic mechanism of g-C3N4/BiOI (001) through hybrid functional calculations based on a first-principle theory. The staggered band structure is observed in the g-C3N4/BiOI...

Exploring the effects of different crystal facet combinations and I-doping in the BiOCl/BiOI heterostructure on photocatalytic properties: a hybrid density functional investigation

“…The BiOX(010) (X = Cl, I) facet has only one stoichiometric surface termination with strong stability, 27 while BiOX(001) facet has three kinds of terminations with different stabilities. 27 Kong et al 28 and Jing et al 29 and our previous investigations 30,31 have demonstrated that the 1X-terminated BiOX(001) (X = Cl, I) surface exhibits much lower surface energy than 2X-terminated BiOX(001) and BiO-terminated BiOX(001) surfaces, and the electronic structure of the 1X-terminated BiOX(001) surface is very similar to that of the bulk. 28–31 Therefore, it is reasonable to consider the BiOX(010) and 1X-terminated BiOX(001) (X = Cl, I) surfaces to construct the specific crystal facet combination interface models with the (001) and (010) facets of BiOCl and BiOI.…”

Surface termination modulation for superior S-Scheme Bi2WO6/BiOI heterojunction photocatalyst: a hybrid density functional study

“…The (001) facet was also mainly investigated both experimentally [59,60] and theoretically [61,62] and is easiest to be exposed in practice [63]. There are three different terminations in the (001) facet, and the 1I-terminated (001) facet (a surface termination for the first layer with I and the subsurface layer with Bi) is the most stable and easiest to expose in experiments [26,64,65]. Therefore, the optimized Bi 2 WO 6 and BiOI unit cells are cleaved along the (001) direction with these terminations.…”

“…By combining the projected band structures and charge transfer mode, the band alignments of Bi 2 WO 6 (DL-O-Bi)/ BiOI(1I), Bi 2 WO 6 (O-Bi)/BiOI(1I), and Bi 2 WO 6 (O-W)/ BiOI(1I) are shown in figures 6(a), (c) and (e), respectively, in contrast to the vacuum level [26,64]. We are delighted to observe that figure 6(a) exhibits a distinct S-scheme character [34,35] in Bi 2 WO 6 (DL-O-Bi)/BiOI(1I), implying superior photocatalytic performance.…”

“…These characteristics lead to a relatively remarkable degradation efficiency of pollutants under visible light [24,25]. Consequently, BiOI was usually an excellent candidate for constructing heterojunction with other semiconductors to furtherly enhance the photocatalytic activity [26].…”

“…and E BiOI are the total energies of the isolated Bi 2 WO 6 and BiOI parts[26,64]. The calculated binding energies of Bi 2 WO 6 (DL-O-Bi)/BiOI(1I), Bi 2 WO 6 (O-Bi)/ BiOI(1I), and Bi 2 WO 6 (O-W)/BiOI(1I) heterostructures are −16.21, −16.19 and −8.04 meV Å −2 , respectively.…”