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Abstract The charge transport in quasi‐2D perovskites limits their applications despite the superior stability and optoelectronic properties. Herein, a novel strategy is proposed to enhance the charge transport by regulating 3D perovskite phase in quasi‐2D perovskite films. The carbohydrazide (CBH) as an additive is introduced into (PEA)2MA3Pb4I13 precursors, which slows down the crystallization process and improves the phase ratio and crystal quality of the 3D phase. This structure change results in a significant improvement in charge transport and extraction, leading to the device demonstrating an almost 100% internal quantum efficiency, a peak responsivity of 0.41 A W−1, and a detectivity of 1.31 × 1012 Jones at 570 nm under 0 V bias. Furthermore, the air and moisture stability of (PEA)2MA3Pb4I13 films is not deteriorated but gets significantly improved due to the better crystal quality and the passivation of defects by the residual CBH molecule. This work demonstrates a strategy for improving the charge transport properties of quasi‐2D perovskites and also sheds light on solving the stability issue of 3D perovskite films via the proper passivation or additives, which will inspire the fast development of the perovskite community.

Staphylococcus aureus has become one of the most common pathogens in clinical tissue infection, and it is easy to form biofilm. Incomplete removal of biofilms often leads to recurrent infections, and more serious is the possibility of bacteria developing drug resistance. Therefore, the effective eradication of refractory biofilms is essential. Herein, a temperature-sensitive hydrogel was prepared by doping the photothermal carbon dots (PTCDs) chelated by Ag+, and the AIPH which could produce alkyl radicals in response to heat into the thermodissolved gelatin. Under the irradiation of 660 nm laser, the PTCDs generated heat to dissolve the hydrogel, and promoted chelation of silver ions in PTCDs for chemical sterilization. Meanwhile, the heat generated by the PTCDs induced the 2,2′-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIPH) to produce alkyl free radical sterilization, achieving the purpose of photothermal/thermodynamic/chemical synergistic to kill Staphylococci aureus and destroy its biofilm. Therefore, the biocompatible PTCDs@Ag-AIPH hydrogel proposed in this study was a promising composite that could eliminate biofilms and promoted wound healing, showing good potential in future biomedical applications.

Abstract Sonodynamic therapy (SDT), a tumor treatment modality with high tissue penetration and low side effects, is able to selectively kill tumor cells by producing cytotoxic reactive oxygen species (ROS) with ultrasound‐triggered sonosensitizers. N‐type inorganic semiconductor TiO2 has low ROS quantum yields under ultrasound irradiation and inadequate anti‐tumor activity. Herein, by using atomic layer deposition (ALD) to create a heterojunction between porous TiO2 and CoOx, the sonodynamic therapy efficiency of TiO2 can be improved. Compared to conventional techniques, the high controllability of ALD allows for the delicate loading of CoOx nanoparticles into TiO2 pores, resulting in the precise tuning of the interfaces and energy band structures and ultimately optimal SDT properties. In addition, CoOx exhibits a cascade of H2O2→O2→·O2− in response to the tumor microenvironment, which not only mitigates hypoxia during the SDT process, but also contributes to the effect of chemodynamic therapy (CDT). Correspondingly, the synergistic CDT/SDT treatment is successful in inhibiting tumor growth. Thus, ALD provides new avenues for catalytic tumor therapy and other pharmaceutical applications.

As the sixth leading cause of cancer death, esophageal cancer is threatening the life of people worldwide. Traditional treatments, such as surgery, chemotherapy, radiotherapy, are facing always augmented challenges including invasion, multidrug resistance (MDR), off-target toxicity. Chemo & Photodynamic synergistic therapy represents one promising strategy for improved treatment efficiency. But it is still hindered by the lack of tumor targeting, deleterious side effects, and unfavorable microenvironment for photodynamic therapy (PDT). To overcome those obstacles, one theranostic nano-assambly drug, GCDs-Ce6/Pt-EGF, was designed and fabricated. Green fluorescence carbon dots (GCDs) with the excellent optical properties, modifiability and low toxicity were prepared as drug carrier. Epidermal growth factor (EGF) was conjugated to the nano-assembly to realize tumor specific targeting. Chlorin e6 (Ce6) in the presence of laser irradiation achieved PDT by generating proapoptosis reactive oxygen species (ROS). Moreover, Ce6 incorporated into GCDs endowed the nano-assambly imaging ability and facilitate image-guided therapy. Pt(IV), cisplatin prodrug, in the nano-assambly depleted the glutathione (GSH) of tumor microenvironment when it was reduced to cytotoxicity Pt(II). Compared with single treatment, GCDs-Ce6/Pt-EGF exhibited enhanced tumor cell killing capacity and better biosafety in vitro and in vivo, especially for EGFR bearing tumor. It paved ways for developing novel theranostic agent to be potentially applied in clinic.

An ultraviolet (UV) signal transmission undergoes rich scattering and strong absorption by atmospheric particulates. We develop a path loss model for a Non-Line-of-Sight (NLOS) link. The model is built upon probability theory governing random migration of photons in free space, undergoing scattering, in terms of angular direction and distance. The model analytically captures the contributions of different scattering orders. Thus it relaxes the assumptions of single scattering theory and provides more realistic results. This allows us to assess the importance of high-order scattering, such as in a thick atmosphere environment, where short range NLOS UV communication is enhanced by hazy or foggy weather. By simulation, it is shown that the model coincides with a previously developed Monte Carlo model. Additional numerical examples are presented to demonstrate the effects of link geometry and atmospheric conditions. The results indicate the inherent tradeoffs in beamwidth, pointing angles, range, absorption, and scattering and so are valuable for NLOS communication system design.