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As an emerging post-graphene two-dimensional (2D) nanomaterial, black phosphorus (BP) is attracting a great deal of current attention for the direct conversion of solar energy into solar fuels on account of its unique tunable direct-bandgap and high charge-carrier mobility. Herein, for the first time, we immobilize BP quantum dots (BPQDs) onto graphitic carbon nitride (g-C 3 N 4 ) nanosheets to create a 0D-2D inorganic-organic hybrid via a conventional and cost–effective sonication approach. The as-prepared BPQDs/g-C 3 N 4 hybrids display BPQD content-dependent performance in visible-light-driven hydrogen generation. 5 wt% BPQDs/g-C 3 N 4 with cyclability exhibits the greatest hydrogen evolution rate of 271 μmol h −1 g −1 that is 5.6 and 4.2 times greater than that of pristine g-C 3 N 4 and BPQDs, respectively. We demonstrate that the type-II band alignment, the formation of phosphorus–carbon bonds and the efficient interfacial charge separation between well-dispersed BPQDs and g-C 3 N 4 synergetically enhance the photoactivity and photostability. This study opens possibilities to create viable BP-based heterostructures for energy conversion and storage. [ABSTRACT FROM AUTHOR]

We consider the fullerene C 70 derivative PC 71 BM as a potential onboard hydrogen storage material. As the cases of many sorbents, metal-decoration is needed to increase the adsorption energy of H 2. We study the metal-decoration by intercalating K atoms into a PC 71 BM film and performing photoelectron spectroscopy measurements. The results reveal that the maximum stoichiometry is K 9 – 10 PC 71 BM. Then we study the hydrogen storage property of an isolated K 9 PC 71 BM molecule with density functional theory calculations. A K 9 PC 71 BM molecule can compactly adsorb 45H 2 (6.22 wt%); the compact adsorption structure does not require large interstitial space in solid phase and thus should be able to be realized in experiments. Considering the poor crystallinity of solid PC 71 BM (with many large interstitial spaces), a gravimetric capacity >7 wt% can be anticipated. The adsorption energy meets the DOE target of onboard operating temperatures, and van der Waals interaction contributes more than 40% of the adsorption energy. [Display omitted] • K-doped PC 71 BM has the hydrogen storage properties meeting DOE 2025 targets. • Van der Waals interaction contributes more than 40% of the adsorption energy. • Fullerene derivatives are a library of hydrogen storage materials. [ABSTRACT FROM AUTHOR]

Abstract: Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04O thin films were fabricated on Si (111) substrate by the reactive magnetron sputtering method at different O-Ar ratios. Detailed characterizations by X-ray diffractometry (XRD), X-ray photo-electronic spectrum (XPS), and electron paramagnetic resonance (EPR) indicate that the doped Cu ions substitute the Zn2+ ions in the ZnO lattice. The doped Cu ions are in Cu+ and Cu2+ mixture valence states. The ferromagnetism of the Zn0.91Co0.05Cu0.04O film increases gradually the increasing Cu+ ions concentration. The results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ ions themselves, but owing to the enhancement of magnetic interaction between Co ions, which suggests that p-type doping of Cu+ ions plays an important role in mediating the ferromagnetic coupling between Co ions. [Copyright &y& Elsevier]