Determination of band offsets at the Al:ZnO/Cu2SnS3 interface using X-ray photoelectron spectroscopy

Abstract

The Al:ZnO/Cu2SnS3 semiconductor heterojunction was fabricated. The structural and optical properties of the semiconductor materials were studied. The band offset at the Al:ZnO/Cu2SnS3 heterojunction was studied using X-ray photoelectron spectroscopy technique. From the measurement of the core level energies and valence band maximum of the constituent elements, the valence band offset was calculated to be −1.1 ± 0.24 eV and the conduction band offset was 0.9 ± 0.34 eV. The band alignment at the heterojunction was found to be of type-I. The study of Al:ZnO/Cu2SnS3 heterojunction is useful for solar cell applications.

Energy Band Architecture of a Hierarchical ZnO/Au/CuxO Nanoforest by Mimicking Natural Superhydrophobic Surfaces

“…The second term, ( E Cu 2p Cu x O – E VBM Cu x O ), is the energy difference between Cu 2p 3/2 and Cu VBM in pure Cu x O, while the third term, ( E Zn 2p ZnO – E VBM ZnO ), is that in pure ZnO. It is noteworthy that Cu x O is an alloy semiconductor with Cu 2 O as the major component; the overall contribution of Cu 2p is mainly Cu 2p 3/2 from Cu 2 O according to previous papers. , Overall, the VBO was calculated as 2.23 eV with detailed steps shown in eq . The calculation of CBO (Δ E C ) requires knowledge of the band gap values, so UV–vis transmittance spectra of Au, pristine Cu x O, pristine ZnO, and ZnO/Au/Cu x O NF on ITO substrates were measured and are shown in Figure a. Band gap values were retrieved with the K–M method, and detailed calculations have already been described in previous papers. , ZnO/Au/Cu x O NF consists of a band gap of ZnO at 3.37 eV and the overall band gap of Cu x O at 2.15 eV.…”

“…ZnO (i) − E Cu 2p Cu x O (i)), in eq 7 represents the energy difference between Zn 2p 3/2 and Cu 2p 3/2 , which was obtained from XPS data in Figure 3 48,51 Overall, the VBO was calculated as 2.23 eV with detailed steps shown in eq 7.…”

Core-Shell Nanostructures of Graphene-Wrapped CdS Nanoparticles and TiO2 (CdS@G@TiO2): The Role of Graphene in Enhanced Photocatalytic H2 Generation

“…The difference of E VBM of pure CdS and pure TiO 2 using valence band XPS is 0.9 eV close to the estimated difference of E VB (0.95 eV) using the Mott-Schottky plot and Eg values (See Table S4). The band alignment at the interface of CdS@50G@TiO 2 samples is also determined by calculating the valence band offset (∆Ev) and conduction band offset (∆Ec) employing the following equations [55,56]:…”