Xiaohong Liu

Bifunctional materials have attracted ongoing interest in the field of detection and removal of contaminants because of their integration of two functions, but they exhibit commonly exceptional performance in only one of these two aspects. The interaction between the two functional units of the bifunctional materials may compromise their sensing and adsorption abilities. Guided by the concept of domain building blocks (DBBs), a hierarchical metal-organic framework (MOF)-on-MOF hybrid was designed by growing gold nanoclusters (AuNCs)-embedded zeolitic imidazolate framework 8 (AuNCs/ZIF-8) on the surface of Zr-MOF (UiO-66-NH₂) for the simultaneous detection and removal of Hg²⁺. In the hybrid, the amino groups (-NH₂) and AuNCs─which were the adsorption groups and sensing units, respectively, were isolated from each other. Specifically, the adsorption groups (-NH₂) were assembled in the inner UiO-66-NH₂ layer, while the sensing units (AuNCs) were confined in the outer ZIF-8 layer. This hierarchical structure not only spatially hindered the electron transfer between these two units but also triggered the aggregation-induced emission of AuNCs because of the confinement of ZIF-8 on the AuNCs, thus changing the fluorescence of AuNCs from quenching to enhancement. The newly prepared UiO-66-NH₂@AuNCs/ZIF-8 hybrid, as expected, showed an ultralow detection limit (0.42 ppb) and a high adsorption capacity (129.9 mg·g^-1) for Hg²⁺. Overall, this work provides a feasible approach to improve the integrated performance of MOF-based composites based on DBBs.

Herein, titanium-dioxide-decorated organic formamidinium lead bromide perovskite thin films grown by the one-step spin-coating method are studied. TiO₂ nanoparticles are widespread in FAPbBr₃ thin films, which changes the optical properties of the perovskite thin films effectively. Obvious reductions in the absorption and enhancements in the intensity of the photoluminescence spectra are observed. Over 6 nm, a blueshift of the photoluminescence emission peaks is observed due to 5.0 mg/mL TiO₂ nanoparticle decoration in the thin films, which originates from the variation in the grain sizes of the perovskite thin films. Light intensity redistributions in perovskite thin films are measured by using a home-built confocal microscope, and the multiple scattering and weak localization of light are analyzed based on the scattering center of TiO₂ nanoparticle clusters. Furthermore, random lasing emission with sharp emission peaks is achieved in the scattering perovskite thin films with a full width at the half maximum of 2.1 nm. The multiple scattering of light, the random reflection and reabsorption of light, and the coherent interaction of light within the TiO₂ nanoparticle clusters play important roles in random lasing. This work could be used to improve the efficiency of photoluminescence and random lasing emissions, and it is promising in high-performance optoelectrical devices.

In recent years, carbon‐based quantum dots as luminophores and co‐reactants have aroused broad interest for their ability to function in electrochemiluminescence (ECL) sensors due to their unique features, including excellent biocompatibility, low toxicity, and water solubility. In this mini review, the synthesis methods of carbon‐based quantum dots are firstly introduced. Then, the mechanism of carbon‐based quantum dots as luminophores and co‐reactants and their latest progress application in the detection of heavy metal ions are explored. Finally, the current challenges and potential future development directions of carbon‐based quantum dots in ECL sensing filed for heavy metal ions analysis are summarized.

Photothermal‐enhanced chemodynamic therapy is a novel and promising strategy for effective tumor treatment. Herein, a kind of polydopamine (PDA)‐based nanoplatform is reported for photothermal‐enhanced chemodynamic therapy against tumor cells. PDA nanoparticles (NPs) were prepared through the self‐polymerization method, which were subsequently chelated with Cu²⁺ and linked with poly(ethylene glycol) (PEG) chains, finally obtaining PDA‐Cu(II)‐PEG NPs. The fabricated PDA‐Cu(II)‐PEG NPs were uniform in shape with a narrow polydispersity. They can firstly react with glutathione (GSH) to generate Cu⁺, inducing GSH depletion meanwhile. The formed Cu⁺ could catalyze H₂O₂ to produce hydroxyl radicals (˙OH) via a Fenton‐like reaction. The formed PDA‐Cu(II)‐PEG NPs displayed good photothermal conversion efficiency and photothermal stability. They can be internalized by 4T1 cells effectively. Under near‐infrared light irradiation, PDA‐Cu(II)‐PEG NPs can generate hyperthermia and ˙OH for photothermal/chemodynamic therapy against tumor cells.

The hybrid organic–inorganic halide perovskite solar cells (PSCs) have attracted considerable attention in the photovoltaic community during the last decade due to unique properties, such as high absorption coefficient, solutionable fabrication, and compatibility with roll-to-roll technology. A certified power conversion efficiency of PSCs as high as 25.2% has been obtained, approaching the levels of silicon solar cells, copper indium gallium selenide (CIGS), and cadmium telluride (CdTe) thin-film solar cells. However, the device area of a PSC is one of the biggest challenges for the commercialize applications. To fabricate large-area PSCs, various fabrication methods have been proposed, including spray coating, slot-die coating, vacuum deposition, and blade coating. Here, the blade-coating technique progress for the PSC fabrication has been reviewed. Moreover, the optimized ways during the solution fabrication process, the efficient strategy for improving the perovskite films' morphology, have also been summarized in this work. In the last part, the challenges and opportunities of PSC commercialization have also been proposed.