Firstly, light with higher energy than bandgap of semiconductor is absorbed and afterwards induces a transition of electrons from the valence band to the conduction band, leaving an equal number of holes in the valence band. Secondly, the excited electrons and holes migrate to the surface. ...
The NH4PbI3has typical structure of perovskites. As it is shown in Fig.1, the NH4+occupies the A site and breaks the symmetry of the convention cubic perovskites. In our calculations, when the atomic positions of A, B and X site are pre-fixed at high-symmetric position, this cubic phas...
Besides, X-ray photoelectron spectroscopy (XPS) is applied to illustrate the chemical composition and chemical valence of Fe and Cu elements in as-prepared CuHCF. As shown in Figs.2d and S2, the sample exhibits mixed valence of Fe3+, Fe2+, Cu2+, and Cu+. Specifically, a pair of peaks...
The initial specific capacity of NVO was measured at 464 mAh g−1, with a capacity retention of 94% after 50 cycles. In contrast, NVO@rGO demonstrated a superior initial capacity of 507 mAh g−1 and exceptional capacity retention, maintaining 100% after the same number of cycles. ...
This transition is attributed to the reduction in the number of neighboring oxygen atoms surrounding the vanadium atoms, leading to an increased electron density in the vicinity of V. Such a phenomenon is indicative of the structural modifications within the VO framework prompted by the integration ...
based on which a large number of polyoxomolybdates have been synthesized. Tellurite units containing Te4+lone pairs have flexible coordination patterns with oxygen atoms, such as TeO3pyramid, TeO4sphenoid, and TeO5square pyramid. The highly distorted acentric structural units of TeOn(n= 3, 4,...
where R is bond length and R0 and B are empirical parameters for given bond type, to confirm protonation state of the decavanadate anion, oxidation number of V, and central atoms of [M(H2O)5(β-HAla)]2+ complex cations. For VV–O bonds, the values R0 = 1.803 Å and B = 0.37 ...