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Flexible perovskite solar cells (f-PSCs) show great promise in portable-power applications (e.g., chargers, drones) and low-cost, scalable productions (e.g., roll-to-roll). However, in conventional n-i-p architecture f-PSCs, the lowtemperature processed metal oxide electron transport layers (ETLs) usually suffer from high resistance and severe defects that limit the power conversion efficiency (PCE) improvement of f-PSCs. Besides the enhancement in the mobility of metal oxide and passivation for perovskite/ETL interfacial defects reported in previous literature, herein, the electron transport loss between the metal oxide nanocrystallines within the ETL is studied by introducing an amorphous F-doped TiO x (F-TiO x ) caulked crystalline SnO 2 composite ETL. The F-TiO x in this novel composite ETL acts as an interstitial medium between adjacent SnO 2 nanocrystallines, which can provide more electron transport channels, effectively passivate oxygen vacancies, and optimize the energy level arrangement, thus significantly enhancing the electron mobility of ETL and reducing the charge transport losses. The composite ETL-based f-PSCs achieve a high PCE of 22.70% and good operational stability. Furthermore, a moderate roughness of the composite ETL endows f-PSCs with superior mechanical reliability by virtue of a strong coupling at the ETL/perovskite interface, by which the f-PSCs can maintain 82.11% of their initial PCE after 4000 bending cycles.

Solar water splitting using semiconductor photocatalysts is considered to be one of the economical and significant techniques for hydrogen evolution. In this study, graphene–ZnxCd1−xS (ZCS) heterojunction is fabricated by hydrothermal method followed by simple photodeposition of ultrathin few layers of molybdenum sulfide (MoS2) nanosheets. The results show that compared with pristine ZCS and 1 wt% graphene mixed ZCS photocatalysts, the 1 wt% graphene and 1 wt% MoS2 photodeposited ZCS composited sample shows 39.5 mmol h−1 g−1 hydrogen production activity, which is 6.9 and 1.9 times significantly higher, respectively, with an apparent quantum yield of 53% at 420 nm visible light is recorded. The improved photocatalytic activity can be attributed to the formation of heterostructure interface between p‐type MoS2 nanosheets with n‐type ZCS host, which allows for the faster transfer of the photogenerated electrons and thus significantly promotes the separation of photogenerated charge carriers.

Structural and physiochemical properties contribute to the biological adaptation of deep-sea animals to their harsh living environment but have hardly been investigated systematically. In the present study, we for the first time applied various material characterization techniques including transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy to investigate the shell microstructures and chemical composition of a deep-sea limpet Eulepetopsis crystallina collected from the Tiancheng hydrothermal vent field at a depth of around 2,700 m in the Southwest Indian Ocean. Analyses of shell microstructural morphology and diffraction patterns of E. crystallina explicitly revealed the layered structures, exfoliation characteristics, and crystallographic orientation of each layer’s unit cell which was tilted at a small angle sequentially. In comparison with ordinary shallow-water limpet Cellana toreuma shells, E. crystallina shells showed a unique chemical composition and contained pure calcite of calcium carbonate polymorph and the trace of phosphate originated from regional phosphatic sediments of the Southwest Indian Ocean. The further microscopic analyses indicated that the shell of the deep-sea limpet E. crystallina features integrated and untruncated layer structures with a compressed width, possibly owning to the ultra-high hydrostatic pressure, which confirmed the effects of the living environment on the shell microstructure of deep-sea animals.