Xin-Xin Jiang

Bio: Xin-Xin Jiang is an academic researcher from Shandong University. The author has contributed to research in topics: Photocatalytic water splitting & Band gap. The author has an hindex of 1, co-authored 1 publications receiving 2 citations.

First principles study of photoelectrochemical water splitting in monolayer Sn2S2P4 with high solar-to-hydrogen efficiency

Abstract: Exploring stable photocatalysts with superior optical absorption and high energy conversion efficiency is the key to water splitting. By means of the first-principles calculations, we report a ternary Sn2S2P4 monolayer with excellent stabilities. Remarkably, the material presents an indirect bandgap of 1.77 eV with the band edge perfectly crossing the redox potential of water. Monolayer Sn2S2P4 exhibits noticeable optical absorption and photocurrent density in the visible range and has adequate driving forces to trigger overall water splitting. Anisotropic and high carrier mobility facilitate the fast transport of photogenerated carriers. Moreover, a solar-to-hydrogen efficiency that reaches as high as 17.51% is theoretically predicted, thereby indicating that the Sn2S2P4 monolayer is a promising candidate for overall photocatalytic water splitting.

Black Phosphorus Field-effect Transistors

Abstract: Two-dimensional crystals have emerged as a class of materials that may impact future electronic technologies. Experimentally identifying and characterizing new functional two-dimensional materials is challenging, but also potentially rewarding. Here, we fabricate field-effect transistors based on few-layer black phosphorus crystals with thickness down to a few nanometres. Reliable transistor performance is achieved at room temperature in samples thinner than 7.5 nm, with drain current modulation on the order of 10(5) and well-developed current saturation in the I-V characteristics. The charge-carrier mobility is found to be thickness-dependent, with the highest values up to ∼ 1,000 cm(2) V(-1) s(-1) obtained for a thickness of ∼ 10 nm. Our results demonstrate the potential of black phosphorus thin crystals as a new two-dimensional material for applications in nanoelectronic devices.

Internal electric field enhanced photoelectrochemical water splitting in direct Z-scheme GeC/HfS2 heterostructure: A first-principles study

Abstract: Designing direct Z-scheme heterostructure photocatalysts has received enormous attention due to the efficient separation of photo-generated carriers in water splitting. Based on first-principles calculations, electronic properties and a photocatalytic mechanism of a GeC/HfS2 van der Waals (vdW) heterostructure are systematically explored. From the analysis of band arrangement and the built-in electric field, the heterostructure, with an indirect bandgap of 0.40 eV, is demonstrated to be a typical direct Z-scheme system. Remarkably, there is also a 0.40 eV interlayer work function difference in the heterostructure, which is helpful to further drive carrier separation and enhance the water splitting ability by partially bending the redox potential of water. The Gibbs calculation shows that the GeC/HfS2 vdW heterostructure can achieve overall photocatalytic water splitting spontaneously under neutral conditions. Moreover, excellent visible light absorption ability ([Formula: see text]) and giant carrier mobilities (5823 cm2 V−1 s−1) also make GeC/HfS2 heterostructure highly competitive in numerous photocatalytic materials and optoelectronic devices. The bandgap can be flexibly adjusted by biaxial strain, enabling a wider application of the heterostructure. All these significant properties not only demonstrate the great application potential of GeC/HfS2 heterostructure as photocatalysis but also provide ideas for designing novel electric field-enhanced heterostructures.