Author(s): Islam, MR (Islam, Md Rasidul); Islam, MS (Islam, Md Sherajul); Mitul, A (Mitul, Abu Farzan); Mojumder, MRH (Mojumder, Md Rayid Hasan); Islam, ASMJ (Islam, A. S. M. Jannatul); Stampfl, C (Stampfl, Catherine); Park, J (Park, Jeongwon)

Source: SCIENTIFIC REPORTS Volume: 11 Issue: 1 Article Number: 17739 DOI: 10.1038/s41598-021-97251-1 Published: SEP 6 2021

Abstract: The photocatalytic characteristics of two-dimensional (2D) GeC-based van der Waals heterobilayers (vdW-HBL) are systematically investigated to determine the amount of hydrogen (H-2) fuel generated by water splitting. We propose several vdW-HBL structures consisting of 2D-GeC and 2D-SiC with exceptional and tunable optoelectronic properties. The structures exhibit a negative interlayer binding energy and non-negative phonon frequencies, showing that the structures are dynamically stable. The electronic properties of the HBLs depend on the stacking configuration, where the HBLs exhibit direct bandgap values of 1.978 eV, 2.278 eV, and 2.686 eV. The measured absorption coefficients for the HBLs are over similar to 10(5) cm(-1), surpassing the prevalent conversion efficiency of optoelectronic materials. In the absence of external strain, the absorption coefficient for the HBLs reaches around 1 x 10(6) cm(-1). With applied strain, absorption peaks are increased to similar to 3.5 times greater in value than the unstrained HBLs. Furthermore, the HBLs exhibit dynamically controllable bandgaps via the application of biaxial strain. A decrease in the bandgap occurs for both the HBLs when applied biaxial strain changes from the compressive to tensile strain. For + 4% tensile strain, the structure I become unsuitable for photocatalytic water splitting. However, in the biaxial strain range of - 6% to + 6%, both structure II and structure III have a sufficiently higher kinetic potential for demonstrating photocatalytic watersplitting activity in the region of UV to the visible in the light spectrum. These promising properties obtained for the GeC/SiC vdW heterobilayers suggest an application of the structures could boost H-2 fuel production via water splitting.

Accession Number: WOS:000694653700041

PubMed ID: 34489541

Author Identifiers:

Author        Web of Science ResearcherID        ORCID Number

Islam, Md. Sherajul                  0000-0002-6717-2523

ISSN: 2045-2322

Full Text: https://www.nature.com/articles/s41598-021-97251-1