Due to their exceptional high energy density, lithium-ion batteries are of central importance in many modern electrical devices. A serious limitation, however, is the slow charging rate used to obtain the full capacity. Thus far, there have been no ways to increase the charging rate without losses in energy density and electrochemical performance. Here we show that the charging rate of a cathode can be dramatically increased via interaction with white light. We find that a direct exposure of light to an operating LiMn₂O₄ cathode during charging leads to a remarkable lowering of the battery charging time by a factor of two or more. This enhancement is enabled by the induction of a microsecond long-lived charge separated state, consisting of Mn⁴⁺ (hole) plus electron. This results in more oxidized metal centers and ejected lithium ions are created under light and with voltage bias. We anticipate that this discovery could pave the way to the development of new fast recharging battery technologies.

Ultrafast photoinduced electron transfer (PIET) dynamics of a C₇₀-encapsulated bisporphyrin covalent organic polyhedron hybrid (C₇₀@COP-5) is studied in a nonpolar toluene medium with fluorescence and transient absorption spectroscopies. This structurally rigid donor (D)–acceptor (A) molecular hybrid offers a new platform featuring conformationally predetermined cofacial D–A orientation with a fixed edge-to-edge separation, R_EE (2.8 Å), without the aid of covalent bonds. Sub-picosecond PIET (τ_ET ≤ 0.4 ps) and very slow charge recombination (τ_CR ≈ 600 ps) dynamics are observed. The origin of these dynamics is discussed in terms of enhanced D–A coupling (V = 675 cm^–1) and extremely small reorganization energy (λ ≈ 0.18 eV), induced by the intrinsic structural rigidity of the C₇₀@COP-5 complex.

The effect of Zr modification on the catalytic activity of Co/SiO₂ was investigated for nonoxidative propane dehydrogenation. Isolated Zr on SiO₂ surface sites were prepared by organometallic synthesis using Zr(O^tBu)₄ as a precursor. The resulting Zr/SiO₂ support was functionalized with Co²⁺ ions via strong electrostatic adsorption. Spectroscopic (diffuse reflectance infrared Fourier transform spectroscopy, UV–vis, electron paramagnetic resonance) and microscopic characterization (transmission electron microscopy, scanning transition electron microscopy) results are consistent with single-site cobalt that preferentially associates with the mono-dispersed Zr at a variety of loadings and Co/Zr ratios. The oxidation state of Co in the as-prepared Co/SiO₂ and Co–Zr/SiO₂ was both +2 with tetrahedral and octahedral geometries, respectively. In situ X-ray absorption near edge structure and extended X-ray absorption fine structure results confirmed that the oxidation state of Co remained as +2 under reaction condition for both Co/SiO₂ and Co–Zr/SiO₂ samples and both catalysts have tetrahedral Co²⁺ as the active catalyst. Despite similar Co coordination environments, the catalytic activity and selectivity was significantly improved by the Zr modification of the silica support versus Co/SiO₂. This was attributed to the change in oxygen donor ability and Co–O bond strength of the ≡SiO–Zr–O sites of Co–Zr/SiO₂ compared with the ≡SiO– ligands in Co/SiO₂. These results show that tuning of the support SiO₂ oxygen donation ability by use of an anchoring site (e.g., ≡SiO–Zr–O^–) can be used to alter both rate and selectivity of propane dehydrogenation with single-site heterogeneous catalysts. These results also show some preference for Co²⁺ active sites to associate with ≡SiO–Zr–O^– sites over ≡SiO–.