TY - JOUR
T1 - Two-dimensional SnS2/ZrSi2N4 van der Waals heterojunction as a spontaneously enhanced hydrogen evolution photocatalyst
AU - Hu, Ying
AU - Xiong, Feilong
AU - Xin, Chaoyi
AU - Wang, Ying
AU - Li, Zhengquan
AU - Luo, Kai Wu
AU - Dong, Kejun
AU - Xu, Liang
N1 - Publisher Copyright:
© 2024 Elsevier Ltd
PY - 2024/12
Y1 - 2024/12
N2 - Photocatalytic water splitting driven by photon excitation is a promising method for generating clean energy. This study focuses on designing a two-dimensional van der Waals heterojunction photocatalyst, created by vertically stacking SnS2 and ZrSi2N4. The intrinsic mechanisms and hydrogen evolution potential of this system were systematically investigated using first-principles calculations. The results demonstrate that the SnS2/ZrSi2N4 heterojunction is a type II heterojunction with an indirect band gap, and the staggered energy bands effectively separate the photogenerated carriers and enhance photocatalytic efficiency. Additionally, the near-ideal band gap of 2.30 eV ensures good light absorption while providing sufficient driving force for water decomposition. The band-edge positions of the heterojunction span the redox potential of water, which means that, in aqueous solutions with a pH range of 0–4, the external potential generated by photogenerated electrons is adequate to spontaneously drive hydrogen evolution through water splitting. Simultaneously, the Gibbs free energy (ΔG = −0.11 eV) being close to zero indicates that this heterojunction can effectively facilitate the hydrogen evolution reaction (HER). Furthermore, the exceptional electron mobility (2048.38 cm2·V−1·S−1), hole mobility (4299.49 cm2·V−1·S−1), and solar-to-hydrogen conversion efficiency of up to 17.92 % underscore its immense potential as an effective photocatalyst. This work offers innovative approaches for achieving efficient photocatalytic water decomposition, advancing the development of clean energy solutions.
AB - Photocatalytic water splitting driven by photon excitation is a promising method for generating clean energy. This study focuses on designing a two-dimensional van der Waals heterojunction photocatalyst, created by vertically stacking SnS2 and ZrSi2N4. The intrinsic mechanisms and hydrogen evolution potential of this system were systematically investigated using first-principles calculations. The results demonstrate that the SnS2/ZrSi2N4 heterojunction is a type II heterojunction with an indirect band gap, and the staggered energy bands effectively separate the photogenerated carriers and enhance photocatalytic efficiency. Additionally, the near-ideal band gap of 2.30 eV ensures good light absorption while providing sufficient driving force for water decomposition. The band-edge positions of the heterojunction span the redox potential of water, which means that, in aqueous solutions with a pH range of 0–4, the external potential generated by photogenerated electrons is adequate to spontaneously drive hydrogen evolution through water splitting. Simultaneously, the Gibbs free energy (ΔG = −0.11 eV) being close to zero indicates that this heterojunction can effectively facilitate the hydrogen evolution reaction (HER). Furthermore, the exceptional electron mobility (2048.38 cm2·V−1·S−1), hole mobility (4299.49 cm2·V−1·S−1), and solar-to-hydrogen conversion efficiency of up to 17.92 % underscore its immense potential as an effective photocatalyst. This work offers innovative approaches for achieving efficient photocatalytic water decomposition, advancing the development of clean energy solutions.
KW - First principle calculations
KW - Hydrogen evolution
KW - Photocatalysis
KW - SnS/ZrSiN heterojunction
KW - Spontaneous reaction
UR - http://www.scopus.com/inward/record.url?scp=85207596730&partnerID=8YFLogxK
U2 - 10.1016/j.mtcomm.2024.110816
DO - 10.1016/j.mtcomm.2024.110816
M3 - Article
AN - SCOPUS:85207596730
SN - 2352-4928
VL - 41
JO - Materials Today Communications
JF - Materials Today Communications
M1 - 110816
ER -