Motivated by recent experimental developments of graphitic-CN (g-CN) sheets, we investigate the suitability of hydrogen storage on Li decorated g-CN via first-principles calculations. We find that the binding energies of Li atoms are very large, ranging from 2.70 to 4.73 eV, which are significantly higher than the cohesive energy of bulk Li. Lithium atoms therefore tend to form 2D rather than 3D patterns on g-CN, promoting reversible hydrogen adsorption and desorption. Remarkably, the average adsorption energy of H₂ molecules falls in the 0.14–0.23 eV range, and the Li decorated CN shows a high theoretical gravimetric density of 10.81 wt%, which is favorable for massive hydrogen storage. Our results suggest that the Li decorated CN could be a promising hydrogen storage material under realistic conditions.

Hybrid structures have attracted a great deal of attention because of their excellent properties, which can open up a way we could not foresee in materials science and device physics. Here, we investigate the electrical and optical behaviors of SiC(GeC)/MoS₂ heterostructures, using first principles calculations based on density functional theory. Non-covalent bonding exists between the junctions due to the weak orbital coupling. Both junctions have optically active band gaps, smaller than that of the SiC or GeC and MoS₂ layers, which result in enhanced optical adsorption under visible-light irradiation. A small number of electrons transfer from SiC/GeC to MoS₂ causing its n-doping. Furthermore, the charge density states of the valence band maximum and the conduction band minimum are localized at different sides, and thus the electron–hole pairs are spatially separated. Our results provide a potential scheme for photovoltaic materials.

Organic intercalation engineering of perovskites endows the as-constructed quasi-2D Dion–Jacobson α-CsPbI ₃ with a linearly aligned bandgap and fundamentally enhanced stability.

In this manuscript, a novel photocatalyst, CdS/BCN composites with CdS nanoparticles in situ grown on BCN nanosheets (CdS/BCN), was synthesized via a simple electrostatic interaction assisted supersaturated recrystallization method. Benefiting from a unique heterostructure, the CdS/BCN composites exhibited highly efficient and stable photocatalytic activity for degrading RhB and methylene blue under visible-light irradiation, and moreover, a high rate constant of 0.115 min⁻¹ has been obtained for degrading RhB, which was much higher than that of most CdS based photocatalysts (0.089 min⁻¹). First-principles calculations revealed that the significantly enhanced photocatalytic activity of the CdS/BCN composite was mainly ascribed to the formed type-II heterojunction and the built-in electric field at the interface between CdS nanoparticles and BCN nanosheets, which promote the transfer of photo-generated electrons between CdS and BCN, and the ˙O₂ ⁻ radical originating from enriched photo-generated electrons was found to be the dominant species that was responsible for the enhanced photocatalytic performance in degrading organic molecules.