Targeted integration of transgenes can be achieved by strategies based on homologous recombination (HR), microhomology-mediated end joining (MMEJ) or non-homologous end joining (NHEJ). The more generally used HR is inefficient for achieving gene integration in animal embryos and tissues, because it occurs only during cell division, although MMEJ and NHEJ can elevate the efficiency in some systems. Here we devise a homology-mediated end joining (HMEJ)-based strategy, using CRISPR/Cas9-mediated cleavage of both transgene donor vector that contains guide RNA target sites and ∼800 bp of homology arms, and the targeted genome. We found no significant improvement of the targeting efficiency by the HMEJ-based method in either mouse embryonic stem cells or the neuroblastoma cell line, N2a, compared to the HR-based method. However, the HMEJ-based method yielded a higher knock-in efficiency in HEK293T cells, primary astrocytes and neurons. More importantly, this approach achieved transgene integration in mouse and monkey embryos, as well as in hepatocytes and neurons in vivo, with an efficiency much greater than HR-, NHEJ- and MMEJ-based strategies. Thus, the HMEJ-based strategy may be useful for a variety of applications, including gene editing to generate animal models and for targeted gene therapies.

Solution processing of semiconductors is highly promising for the high-throughput production of cost-effective electronics and optoelectronics. Although hybrid perovskites have potential in various device applications, challenges remain in the development of high-quality materials with simultaneously improved processing reproducibility and scalability. Here, we report a liquid medium annealing (LMA) technology that creates a robust chemical environment and constant heating field to modulate crystal growth over the entire film. Our method produces films with high crystallinity, fewer defects, desired stoichiometry, and overall film homogeneity. The resulting perovskite solar cells (PSCs) yield a stabilized power output of 24.04% (certified 23.7%, 0.08 cm2) and maintain 95% of their initial power conversion efficiency (PCE) after 2000 hours of operation. In addition, the 1-cm2 PSCs exhibit a stabilized power output of 23.15% (certified PCE 22.3%) and keep 90% of their initial PCE after 1120 hours of operation, which illustrates their feasibility for scalable fabrication. LMA is less climate dependent and produces devices in-house with negligible performance variance year round. This method thus opens a new and effective avenue to improving the quality of perovskite films and photovoltaic devices in a scalable and reproducible manner.

The mixtures of cations and anions used in hybrid halide perovskites for high-performance solar cells often undergo element and phase segregation, which limits device lifetime. We adapted Schelling’s model of segregation to study individual cation migration and found that the initial film inhomogeneity accelerates materials degradation. We fabricated perovskite films (FA 1–x Cs x PbI 3 ; where FA is formamidinium) through the addition of selenophene, which led to homogeneous cation distribution that retarded cation aggregation during materials processing and device operation. The resultant devices achieved enhanced efficiency and retained >91% of their initial efficiency after 3190 hours at the maximum power point under 1 sun illumination. We also observe prolonged operational lifetime in devices with initially homogeneous FACsPb(Br 0.13 I 0.87 ) 3 absorbers.

Organic–inorganic hybrid perovskite solar cells (PSCs) have demonstrated high efficiency and improved stability, which shows promising potential for commercialization. However, among all challenges, the material and device instability of the methylammonium lead iodide (MAPbI3) absorber are regarded as serious obstacles to the future development of devices for long‐term operation. Compared with conventional MAPbI3, formamidinium lead iodide (FAPbI3) and cesium lead iodide (CsPbI3) have attracted more attention due to their superior thermal stability. Due to their undesirable tolerant factor, however, these materials suffer from poor phase stability, which is worthy of careful investigation. This perspective highlights the recent progress on the phase stabilization of FAPbI3 and inorganic CsPbI3 materials with emphasis on the fundamental understanding of the origin of phase instability. In addition, strategies to fabricate corresponding devices toward high‐efficiency and long‐lifetime are discussed. This review sheds light onto the design and synthesis of FAPbI3 and inorganic CsPbI3 perovskite materials. In the end, the potential of FAPbI3 and inorganic CsPbI3 perovskite materials as stable absorbers is discussed, which promotes the development of corresponding solar cells and other optoelectronic devices for practical applications.

The ZnHCF//Zn hybrid aqueous battery with selected K+ insertion/extraction shows a discharge plateau of 1.937 V at 2C.

Since the first room temperature lead halide perovskite light-emitting diode (PeLED) reported in 2014, [5] green, red, and near-infrared PeLEDs have been developed rapidly, with external quantum efficiency (EQE) all over 20%. [6][7][8][9][10][11][12] However, the EQE of blue PeLEDs is still lagging behind, [13][14][15][16] which undoubtedly restricts their applications in full-color displays and white-light illuminations. [2,[17][18][19] Recently, quasi-2D perovskites have been considered as emerging candidates for efficient blue emission, with high exciton binding energy and efficient radiative recombination, thanks to the quantum confinement and dielectric confinement effects. [20][21][22][23] In quasi-2D perovskites, large organic ligands such as butylammonium (BA + ) and phenylethylammonium (PEA + ) can divide the perovskite lattice into a finite number of inorganic monolayers (n) and form quantum wells. While quasi-2D perovskites offer a feasible approach for high-efficiency blue PeLEDs, the elaborate control over the distribution of n domains presents a rising challenge. [24] Solution processed quasi-2D perovskites often contain a mixture of n phases with various bandgaps. [24,25] While quasi-two-dimensional (quasi-2D) perovskites have emerged as promising semiconductors for light-emitting diodes (LEDs), the broad-width distribution of quantum wells hinders their efficient energy transfer and electroluminescence performance in blue emission. In particular, the underlying mechanism is closely related to the crystallization kinetics and has yet to be understood. Here for the first time, the influence of bifunctional zwitterions with different coordination affinity on the crystallization kinetics of quasi-2D perovskites is systematically investigated. The zwitterions can coordinate with Pb 2+ and also act as co-spacer organic species in quasi-2D perovskites, which collectively inhibit the aggregation of colloidal precursors and shorten the distance of quantum wells. Consequently, restricted nucleation of high-n phases and promoted growth of low-n phases are achieved with moderately coordinated zwitterions, leading to the final film with a more concentrated n distribution and improved energy transfer efficiency. It thus enables high-efficiency blue LEDs with a recorded external quantum efficiency of 15.6% at 490 nm, and the operation stability has also been prolonged to 55.3 min. These results provide useful directions for tuning the crystallization kinetics of quasi-2D perovskites, which is expected to lead to high-performance perovskite LEDs.

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