The crystal distortion such as lattice strain and defect located at the surfaces and grain boundaries induced by soft perovskite lattice highly determines the charge extraction-transfer dynamics and recombination to cause an inferior efficiency of perovskite solar cells (PSCs). Herein, the authors propose a strategy to significantly reduce the superficial lattice tensile strain by means of incorporating an inorganic 2D Cl-terminated Ti 3 C 2 (Ti 3 C 2 Cl x ) MXene into the bulk and surface of CsPbBr 3 film. Arising from the strong interaction between Cl atoms in Ti 3 C 2 Cl x and the under-coordinated Pb 2+ in CsPbBr 3 lattice, the expanded perovskite lattice is compressed and confined to act as a lattice "tape", in which the Pb-Cl bond plays a role of "glue" and the 2D Ti 3 C 2 immobilizes the lattice. Finally, the defective surface is healed and a champion efficiency as high as 11.08% with an ultrahigh open-circuit voltage up to 1.702 V is achieved on the best all-inorganic CsPbBr 3 PSC, which is so far the highest efficiency record for this kind of PSCs. Furthermore, the unencapsulated device demonstrates nearly unchanged performance under 80% relative humidity over 100 days and 85°C over 30 days.

Interfacial passivation of defective perovskite films with a dipole molecule shows a great potential for high-efficiency perovskite solar cells (PSCs). Herein, by regulating the side group of an aniline-based molecule with an electron-withdrawing nitryl (−NO2) or electron-donating methoxyl (−OCH3), the binding energy between −NH2 and under-coordinated Pb2+ in the CsPbBr3 lattice is reinforced, and the dipole-moment-induced surface energy level reconstruction allows for efficient hole extraction for the −OCH3-tailored molecule because of the changed intramolecular electron distribution, whereas −NO2 displays the opposite effect. Finally, the all-inorganic CsPbBr3 PSC achieves a power conversion efficiency (PCE) of 9.81% with an open-circuit voltage (V oc) of 1.632 V and an excellent stability in both high humidity and light irradiation. Upon doping Sm3+ into CsPbBr3, the PCE and V oc are further increased to 10.75% and 1.675 V. This work confirms the importance of a side group on an interface dipole molecule to maximize the charge scavenging, especially for V oc improvement.

One great challenge for perovskite solar cells (PSCs) lies in their poor operational stability under harsh stimuli by humidity, heat, light, etc. Herein, a thermal‐triggered self‐healing polyurethane (PU) is tailored to simultaneously improve the efficiency and stability of inorganic CsPbIBr2 PSCs. The dynamic covalent disulfide bonds between adjacent molecule chains in PU at high temperatures self‐heal the in‐service formed defects within the CsPbIBr2 perovskite film. Finally, the best device free of encapsulation achieves a champion efficiency up to 10.61 % and an excellent long‐term stability in an air atmosphere over 80 days and persistent heat attack (85 °C) over 35 days. Moreover, the photovoltaic performances are recovered by a simple heat treatment.

These inhomogeneous defects in turn causes an accelerated charge recombination and a poor durability if they cannot be timely eliminated during the practical application. Therefore, it is a challenge to make a real-time self-healing Healing charge-selective contact interfaces in perovskite solar cells (PSCs) highly determines the power conversion efficiency (PCE) and stability. However, the state-of-the-art strategies are often static by oneoff formation of a functional interlayer, which delivers fixed interfacial properties during the subsequent operation. As a result, defects formed in-service will gradually deteriorate the photovoltaic performances. Herein, a dynamic healing interface (DHI) is presented by incorporating a low-melting-point small molecule onto perovskite film surface for highly efficient and stable PSCs. Arising from the reduced non-radiative recombination, the DHI boosts the PCE to 12.05% for an all-inorganic CsPbIBr 2 solar cell and 14.14% for a CsPbI 2 Br cell, as well as 23.37% for an FA 0.92 MA 0.08 PbI 3 (FA = formamidinium, MA = methylammonium) cell. The solid-to-liquid phase conversion of DHI at elevated temperature causes a longitudinal infiltration into the bulk perovskite film to maximize the charge extraction, passivate defects at grain boundaries, and suppress ion migration. Furthermore, the stability is remarkably enhanced under air, heat, and persistent light-irradiation conditions, paving a universal strategy for advanced perovskite-based optoelectronics.

Effective theranostic probes in cancer therapy are still a challenge. We report the selective killing of cancer cells upon photothermal ablation using a new class of 2,5-deoxyfructosazine-coated green-emissive carbon dots using mild LED-irradiation.

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The use of the human papillomavirus (HPV) vaccine was recently approved in Mainland China. This study determined the knowledge and attitudes of young women aged 20 to 35 years in Fujian Province, China, with regard to HPV and vaccination and explored the potential factors influencing their attitudes toward HPV vaccination. This was a cross-sectional study that collected data regarding the knowledge on and attitudes toward HPV and vaccination using questionnaires. Furthermore, the prevalence of HPV was determined from the sampled participants. A total of 1001 young women were included in the survey. This study demonstrated that the HPV prevalence rate was 15.7% (157/1001). Among all patients, 44.9% (n = 449) had heard of HPV; however, detailed knowledge about HPV was lacking. The majority (83.7%) expressed a willingness to be vaccinated. Specifically, knowledge of the dangers of HPV infection was significantly associated with the willingness to be vaccinated. In this study, women cited some concerns and expressed high expectations for the HPV vaccine, but the costs of vaccination reduced their willingness to be vaccinated. This study found that most patients did not have a detailed knowledge of HPV. Thus, there is a need for continued HPV promotion and education efforts, especially on the dangers of HPV infection, among young women aged 20 to 35 years in Fujian Province, China. Furthermore, it is important to subsidize the costs of vaccination for promoting vaccination campaigns in China.

Bandgap-tunable mixed-halide perovskites offer exciting opportunities to construct efficient multijunction tandem solar cells. However, the ion migration always causes halide segregation, which inevitably creates detrimental defects and deteriorates the photovoltaic performances. Here, we report a universal caging strategy to suppress halide segregation by in situ formation of conjugated covalent organic frameworks (COFs) catalyzed by PbX2 (X = Br and I) during the formation of mixed-halide perovskite. Through theoretical calculation and systematic investigation, the strong electron-donating feature of COFs is shown to effectively solidify the soft lattice and impede the iodide ion transport from bulk to grain boundary, decelerating the light-induced halide-demixing process. Finally, the nonradiative recombination is significantly reduced, boosting efficiency up to 11.50% for an inorganic CsPbIBr2 perovskite solar cell and 14.35% for a CsPbI2Br cell with a prolonged shelf life and an improved photostability.