Rhenium(I)-carbonyl-diimine complexes have emerged as promising photocatalysts for carbon dioxide reduction with covalent organic frameworks recognized as perfect sensitizers and scaffold support. Such Re complexes/covalent organic frameworks hybrid catalysts have demonstrated high carbon dioxide reduction activities but with strong excitation energy-dependence. In this paper, we rationalize this behavior by the excitation energy-dependent pathways of internal photo-induced charge transfer studied via transient optical spectroscopies and time-dependent density-functional theory calculation. Under band-edge excitation, the excited electrons are quickly injected from covalent organic frameworks moiety into catalytic RheniumI center within picosecond but followed by fast backward geminate recombination. While under excitation with high-energy photon, the injected electrons are located at high-energy levels in RheniumI centers with longer lifetime. Besides those injected electrons to RheniumI center, there still remain some long-lived electrons in covalent organic frameworks moiety which is transferred back from RheniumI. This facilitates the two-electron reaction of carbon dioxide conversion to carbon monoxide.

V3O7·H2O nanobelts/reduced graphene oxide (rGO) composites (weight ratio: 86%/14%) are synthesized by a microwave approach with a high yield (85%) through controlling pH with acids. The growth mechanisms of the highly crystalline nanobelts (average diameter: 25 nm; length: ≈20 µm; oriented along the [101] direction) have been thoroughly investigated, with the governing role of the acid upon the morphology and oxidation state of vanadium disclosed. When used as the ZIB cathode, the composite can deliver a high specific capacity of 410.7 and 385.7 mAh g−1 at the current density of 0.5 and 4 A g−1, respectively, with a high retention of the capacity of 93%. The capacity of the composite is greater than those of V3O7 · H2O, V2O5 nanobelts, and V5O12 · 6H2O film. Zinc ion storage in V3O7·H2O/rGO is mainly a pseudocapacitive behavior rather than ion diffusion. The presence of rGO enables outstanding cycling stability of up to 1000 cycles with a capacity retention of 99.6%. Extended cycling shows a gradual phase transition, that is, from the original orthorhombic V3O7 · H2O to a stable hexagonal Zn3(VO4)2(H2O)2.93 phase, which is a new electrochemical route found in V3O7 materials. This phase transition process provides new insight into the reactions of aqueous ZIBs.

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hampered to date by the limited success in the development of clinical photothermal therapy agents. [6] PTT exploits heat generated locally by a photosensitizer, [7] in which both the photothermal agents and laser sources, as well as the matching between them, are essential. Laser thermal therapy generally employs continuouswave lasers with wavelengths of either 808 or 980 nm. [8,9] The wavelengths are in the near-IR (NIR, λ = 700-1100 nm) window so that photons can penetrate deep into biological tissue. [10][11][12] Certain nanoparticles (NPs) have proper carrier densities enabling them to exhibit localized surface plasmon resonances (LSPRs) that efficiently facilitate the conversion of NIR light into heat. [10][11][12] Several types of NPs are currently being developed as photosensitizers, including metallic and semiconductor NPs. Noble metal NPs, for example, Ag and Au NPs, have been extensively applied for the LSPRs in the visible spectrum. [5,[13][14][15] Semi conductor NPs have tunable carrier concentration and LSPRs typically in the NIR range. [10,11] A high photothermal conversion efficiency is key to effective NP photosensitizers to avoid thermal damage to healthy tissue, which is a serious problem in PTT. The NPs with a high photothermal conversion efficiency and tumor selectivity can thus effectively destroy the cancer cells at a low photon density and in a short treatment time, while keeping the surrounding healthy tissue at a safe temperature. [16] Other key factors to consider for developing Photothermal therapy requires efficient plasmonic nanomaterials with small size, good water dispersibility, and biocompatibility. This work reports a one-pot, 2-min synthesis strategy for ultrathin CuS nanocrystals (NCs) with precisely tunable size and localized surface plasmon resonance (LSPR), where a single-starch-layer coating leads to a high LSPR absorption at the near-IR wavelength 980 nm. The CuS NC diameter increases from 4.7 (1 nm height along [101]) to 28.6 nm (4.9 nm height along [001]) accompanied by LSPR redshift from 978 to 1200 nm, as the precursor ratio decreases from 1 to 0.125. Photothermal temperature increases by 38.6 °C in 50 mg L −1 CuS NC solution under laser illumination (980 nm, 1.44 W cm −2 ). Notably, 98.4% of human prostate cancer PC-3/Luc+ cells are killed by as little as 5 mg L −1 starch-coated CuS NCs with 3-min laser treatment, whereas CuS NCs without starch cause insignificant cell death. LSPR modeling discloses that the starch layer enhances the photothermal effect by significantly increasing the free carrier density and blue-shifting the LSPR toward 980 nm. This study not only presents a new type of photothermally highly efficient ultrathin CuS NCs, but also offers in-depth LSPR modeling investigations useful for other photothermal nanomaterial designs.

Fe3O4 nanoparticles are successfully introduced inside multi-walled carbon nanotubes (Fe3O4@MWNTs) by an innovative wet chemical injection method.