The direct Z-scheme character and roles of S vacancy in BiOCl/Bi₂S₃-(001) heterostructures for superior photocatalytic activity: a hybrid density functional investigation

Abstract

In view of some current speculations and controversies regarding the type of BiOCl/Bi2S3-(001) heterostructure in experiments, it is of great importance to clarify the controversies and further explain the relevant...

Strain and Electric Field Engineering of G-ZnO/SnXY (X, Y = S, Se) S-Scheme Heterostructures for Photocatalyst and Electronic Device Applications: A Hybrid DFT Calculation

“…After contact, the electrons transfer from g-ZnO to SnXY due to the E f difference between them, making g-ZnO positively charged, SnXY layers receive electrons and are negatively charged, and E int from g-ZnO to SnXY thus formed. E int in g-ZnO/SnS 2 and g-ZnO/SnSSe are 0.35 and 0.43 V/Å, respectively, larger than that of many reported photocatalytic heterostructures such as V Br -CsSnBr 3 /SnS 2 (0.25 V/Å), RP/CH 3 NH 3 PbI 3 (0.059 V/Å), BiOCl/Bi 2 S 3 -(001) (0.14 V/Å), BiOCl/V S -Bi 2 S 3 -(001) (0.19 V/Å), and Bi 2 WO 6 (DL-O–Bi)/BiOI­(1I) (0.09 V/Å) . When g-ZnO and SnXY are activated by light illumination, photogenerated electrons and holes exist.…”

“…In vdWHs, the electrostatic potential difference (ΔV H ) still exists, which reflects the strength of E int to some extent. ,, E int provides the driving force for the migration of photogenerated carriers between g-ZnO and SnXY , E int = Q ε 0 ε r A e r where Q represents the number of electron transfer between g-ZnO and SnXY, which can be obtained through Bader charge analysis …”

“…27,54,55 E int provides the driving force for the migration of photogenerated carriers between g-ZnO and SnXY. 56 E int can be calculated using the parallel-plate capacitor model: 57,58…”

Constructing hollow core–shell Z-scheme heterojunction CdS@CoTiO3 nanorods for enhancing the photocatalytic degradation of 2,4-DCP and TC

“…4a, the absorption edge of the CdS NPs was about 550 nm, concurring with related reports. 13 The pure CoTiO 3 NRs displayed optical adsorption properties both in the UV and visible-light regions. Furthermore, absorption peaks centered at about 538 and 605 nm were observed, which could be indexed to metal-to-metal charge transfer (Co 2+ to Ti 4+ ).…”

“…4,5 In particular, by forming a Z-scheme heterojunction, a wide light-absorption range and sufficient redox capacity can be simultaneously achieved, ascribed to the Z-scheme charge-transfer path with the assistance of the built-in electric field in the heterojunction region, which can thus enhance the photocatalytic performance. 6–9 Recently, a number of Z-scheme heterojunctions such as g-C 3 N 4 /MoS 2 , 10 CdIn 2 S 4 /ZnS, 11 CoS x /CdS, 12 and BiOCl/Bi 2 S 3 13 have been constructed with the aim of achieving excellent photocatalytic performances. Additionally, assembling low-dimensional nanoscale building blocks to form hierarchical hollow configurations is reported as another commendable method for improving the photocatalytic performance.…”