A black phosphorus (BP)-based drug delivery system for synergistic photodynamic/photothermal/chemotherapy of cancer is constructed. As a 2D nanosheet, BP shows super high drug loading capacity and pH-/photoresponsive drug release. The intrinsic photothermal and photodynamic effects of BP enhance the antitumor activities. The synergistic photodynamic/photothermal/chemotherapy makes BP-based drug delivery system a multifunctional nanomedicine platform.

All-inorganic Pb-free bismuth (Bi) halogen perovskite quantum dots (PQDs) with distinct structural and photoelectric properties provide plenty of room for selective photoreduction of CO 2 . However, the efficient conversion of CO 2 -to-CO with high selectivity on Bi-based PQDs driven by solar light remains unachieved, and the precise reaction path/ mechanism promoted by the surface halogen-associated active sites is still poorly understood. Herein, we screen a series of nontoxic and stable Cs 3 Bi 2 X 9 (X = Cl, Br, I) PQDs for selective photocatalytic reduction of CO 2 -to-CO at the gas−solid interface. Among all the reported pure-phase PQDs, the assynthesized Cs 3 Bi 2 Br 9 PQDs exhibited the highest CO 2 -to-CO conversion efficiency generating 134.76 μmol g −1 of CO yield with 98.7% selectivity under AM 1.5G simulated solar illumination. The surface halogen-associated active sites and reaction intermediates were dynamically monitored and precisely unraveled based on in situ DRIFTS investigation. In combination with the DFT calculation, it was revealed that the surface Br sites allow for optimizing the coordination modes of surfacebound intermediate species and reducing the reaction energy of the rate-limiting step of COOH − intermediate formation from • CO 2 − . This work presents a mechanistic insight into the halogen-involved catalytic reaction mechanism in solar fuel production.

Transition-metal dyshomeostasis is recognized as a critical pathogenic factor at the onset and progression of neurodegenerative disorder (ND). Excess transition-metal ions such as Cu can catalyze the generation of cytotoxic reactive oxygen species and thereafter induce neuronal cell apoptosis. Exploring new chelating agents, which are not only capable of capturing excess redox-active metal, but can also cross the blood-brain barrier (BBB), are highly desired for ND therapy. Herein, it is demonstrated that 2D black phosphorus (BP) nanosheets can capture Cu efficiently and selectively to protect neuronal cells from Cu -induced neurotoxicity. Moreover, both in vitro and in vivo studies show that the BBB permeability of BP nanosheets is significantly improved under near-infrared laser irradiation due to their strong photothermal effect, which overcomes the drawback of conventional chelating agents. Furthermore, the excellent biocompatibility and stability guarantee the biosafety of BP in future clinical applications. Therefore, these features make BP nanosheets have the great potential to work as an efficient neuroprotective nanodrug for ND therapy.

Photocatalytic CO2 conversion into valuable solar fuels is highly appealing, but lack of directional charge-transfer channel and insufficient active sites resulted in limited CO2 reduction efficiency and selectivity for most photocatalytic systems. Herein, we designed and fabricated rare-earth La single-atoms on carbon nitride with La–N charge-transfer bridge as the active center for photocatalytic CO2 reaction. The formation of La single-atoms was certified by spherical aberration-corrected HAADF-STEM, STEM-EELS, EXAFS, and theoretical calculations. The electronic structure of the La–N bridge enables a high CO-yielding rate of 92 μmol·g–1·h–1 and CO selectivity of 80.3%, which is superior to most g-C3N4-based photocatalytic CO2 reductions. The CO production rate remained nearly constant under light irradiation for five cycles of 20 h, indicating its stability. The closely combined experimental and DFT calculations clearly elucidated that the variety of electronic states induced by 4f and 5d orbitals of the La single atom and the p–d orbital hybridization of La–N atoms enabled the formation of charge-transfer channel. The La–N charge bridges are found to function as the key active center for CO2 activation, rapid COOH* formation, and CO desorption. The present work would provide a mechanistic understanding into the utilization of rare-earth single-atoms in photocatalysis for solar energy conversion.

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With black phosphorus (BP) as an example, the first two-dimensional (2D) semiconductor based sonosensitizer (Au@BP nanohybrids) was fabricated. Under ultrasound irradiation, Au@BP nanohybrids can generate O in deep tissues and eradicate tumors with high efficacy. This platform paves the way for the application of 2D semiconductors in sonodynamic cancer therapy.

Fabrication of clinically translatable nanoparticles (NPs) as photothermal therapy (PTT) agents against cancer is becoming increasingly desirable, but still challenging, especially in facile and controllable synthesis of biocompatible NPs with high photothermal efficiency. A new strategy which uses protein as both a template and a sulfur provider is proposed for facile, cost‐effective, and large‐scale construction of biocompatible metal sulfide NPs with controlled structure and high photothermal efficiency. Upon mixing proteins and metal ions under alkaline conditions, the metal ions can be rapidly coordinated via a biuret‐reaction like process. In the presence of alkali, the inert disulfide bonds of S‐rich proteins can be activated to react with metal ions and generate metal sulfide NPs under gentle conditions. As a template, the protein can confine and regulate the nucleation and growth of the metal sulfide NPs within the protein formed cavities. Thus, the obtained metal sulfides such as Ag2S, Bi2S3, CdS, and CuS NPs are all with small size and coated with proteins, affording them biocompatible surfaces. As a model material, CuS NPs are evaluated as a PTT agent for cancer treatment. They exhibit high photothermal efficiency, high stability, water solubility, and good biocompatibility, making them an excellent PTT agent against tumors. This work paves a new avenue toward the synthesis of structure‐controlled and biocompatible metal sulfide NPs, which can find wide applications in biomedical fields.

Lead (Pb) halide perovskite quantum dots (PQDs) are promising candidates for the photochemical reduction of CO 2 . However, the intrinsically weak adsorption and activation toward inert CO 2 molecules have seriously hindered their practical application. This study reports alternative Cs 2 CuBr 4 PQDs for gas−solid phase photocatalytic CO 2 reduction under simulated solar irradiation. Cs 2 CuBr 4 PQDs exhibited CO 2 photoreduction performance with CH 4 and CO yields of 74.81 and 148.98 μmol g −1 , respectively. In situ diffuse reflectance infrared Fourier transform spectra and density functional theory calculations cooperatively revealed the synergistic strengthening of microelectronic polarization in Cs 2 CuBr 4 PQDs induced by surface-frustrated Lewis pair-like properties and intrinsic Cu d-band properties facilitated robust CO 2 adsorption and activation. This study demonstrated the potential of Cs 2 CuBr 4 PQDs as a platform for highly efficient CO 2 photoreduction and provided a distinct concept for CO 2 adsorption and activation based on the catalytic mechanism of Cu-based PQDs. KEYWORDS: photocatalytic CO 2 reduction, Cs 2 CuBr 4 , perovskite quantum dots, CO 2 adsorption and activation, catalytic mechanism