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Amino trimethylene phosphonic (ATMP) acid can effectively control the crystal growth of TiO2 to get preferable energy level and topography. High VOC and PCE were achieved for ATMP–TiO2 based perovskite solar cells.

The industrialization of perovskite solar cells (PSCs) is based on the development of efficiency and stability. Here, a composite film of a polyethylenimine ethoxylated (PEIE) and tellurophene-based two-dimensional metal–organic framework (2D MOF) was introduced to realize the nondestructive passivation of TiO2. This interfacial layer can not only realize the effective passivation of TiO2, but can also further improve the morphology of the perovskite film. After the modification of the PEIE-2D MOF composite film, the morphology and crystallinity of the perovskite film are greatly optimized, the trap states in the TiO2 layer are reduced, and the electron transport in the device is enhanced, thus finally achieving highly efficient and stable FA0.25MA0.75PbI3 PSCs with a maximum efficiency of 22.22%. It was demonstrated that the reduced trap states and the smooth surface of the TiO2 electron transport layer are the reasons for the high performance of modified PSCs. This method provides a new way for improving the interface state to achieve highly efficient and stable PSCs.

With the development and popularization of medical wearable devices, medical practice and health care provision are changing. However, the resulting daily large amount of personal data and privacy disclosure and other ethical issues related to interests are gradually highlighted. From the perspective of medical ethics, this paper summarizes and analyzes the ethical problems existing in the whole process of health medical wearable equipment serving human beings, including the equipment itself, data collection, data transmission, and management, and data use and puts forward corresponding countermeasures and suggestions from the perspectives of respecting autonomy, informed consent, privacy protection, medical optimization, and favorable principles. “Prevention before disease, disease prevention, and change prevention”, and “medicine according to the case”, to give full play to the role of health care wearables in the field of medical care, promote the development of new intelligent medical care and help the construction of healthy China.

Organometallic halide perovskites have rapidly become promising materials as a result of their outstanding properties in high-efficiency and low-cost next-generation solar cells. Perovskite materials can be adjusted to be p- or n-type by defect engineering through, for example, the self-doping method by controlling the precursor compositions and process conditions. Recently, a p-type perovskite/n-type perovskite homojunction has been proposed and constructed, which provides a possibility for the design of a novel type of perovskite solar cell (PSC). Following a brief overview of the physical fundamentals of perovskite homojunctions, a detailed discussion of the promising progress of recently reported homojunction PSCs is presented here, including theoretical simulations, extrinsic and interfacial doping and graded structures. Furthermore, the opportunities regarding higher doping concentrations, simpler device architectures, ion migration inhibition and device stability are discussed. Finally, an outlook that offers insights into the future development of highly efficient and stable homojunction PSCs is provided.

An organocatalyst system, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and nBu4NCl, was developed for the conversion of CO2 and internal epoxides to the corresponding disubstituted cyclic carbonates under rather mild conditions (1–4 atm of CO2 and 100–120 °C). Catalyst screening revealed that small Cl− opens epoxide rings more effectively than larger Br− and I− do when used as the counter anion of nBu4N+, suggesting that the steric hindrance of the internal epoxides is a factor. A practical and economical alternative system, DBU and nBuCl, is also presented.

A highly simple, economical, and selective synthesis of five-membered cyclic carbonates was achieved by the reaction of CO2 with 1,2-halohydrins in the presence of K2CO3. This method allows the efficient preparation of cyclic carbonates (72–95% yields for monosubstituted cyclic carbonates and 43% for 1,1- and 1,2-disubstituted cyclic carbonates) under mild reaction conditions, atmospheric pressure of CO2 at 30 °C, and not only in dry DMF, but also in commercial “anhydrous” DMF. The reaction mechanism was elucidated using the SEM and XRD data of the by-products, KHCO3 and KBr.

A highly simple, economical, and selective synthesis of five-membered cyclic carbonates was achieved by the reaction of CO2 with 1,2-halohydrins in the presence of K2CO3. This method allows the efficient preparation of cyclic carbonates (72–95% yields for monosubstituted cyclic carbonates and 43% for 1,1- and 1,2-disubstituted cyclic carbonates) under mild reaction conditions, atmospheric pressure of CO2 at 30 °C, and not only in dry DMF, but also in commercial “anhydrous” DMF. The reaction mechanism was elucidated using the SEM and XRD data of the by-products, KHCO3 and KBr.