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Converting non‐visual light into photocurrent while maintaining high visual transparency is vital for semitransparent organic solar cells (ST‐OSCs) application, yet often challenging over insufficient invisible light‐harvesting. Herein, spectrally selective optical manipulation for ST‐OSCs with high visual light transparency and full‐spectral non‐visual light reflection is proposed by matching the optical admittance of ultrathin Ag films using ZnS and MgF2. The reflection of optically enhanced ST‐OSCs at the spectral region beyond the human eye's response spectrum is improved and the transmission in the visual region is simultaneously enhanced. By further integrating an anti‐reflective structure, the optimal structure boosts the average visible transmittance and power conversion efficiency of ST‐OSCs to 44.3% and 12.6%, respectively, yielding a record light utilization efficiency of 5.6%. Corresponding flexible ST‐OSCs with high mechanical stability implies that this work provides a facile and universal strategy for ST‐OSCs aiming at building integrated photovoltaics. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) have been known as the most widely used light source in lighting and displays for more than 60 years. There is still room for progress in the performance of LEDs, especially since the current devices with various types of different light-emitting layer materials have converged to unity in terms of internal quantum efficiency, and there is an urgent need to improve the light extraction efficiency. Metasurfaces (MSs) have received attention from researchers as structures that can be integrated with LEDs to efficiently modulate the phase and amplitude of light through resonance and scattering, which can reduce light loss. This paper reviews the development of metasurfaces in LEDs so far. The different working mechanisms of metasurfaces composed of different materials are first analyzed in depth. Subsequently, three aspects of light extraction, angle change, and polarization modulation are described in detail according to different applications of metasurfaces in LEDs. Finally, the current status of metasurface applications in LEDs is summarized, and the future development prospects are envisioned. [ABSTRACT FROM AUTHOR]

Photodiode‐type solar‐blind photodetectors (SBPDs) with the self‐powered feature hold great promise for applications in unattended secure communication, flame detection, and missile warning. However, the responsivity of SBPDs is usually limited due to the severe solar‐blind (SB) light extinction in substrates and charge transport layers. Herein, a spectrally selective hole extraction structure (SHE) is proposed for high‐efficiency perovskite SBPDs. The SHE consisting of a tandem Fabry–Perot cavity and energy‐level‐matched hole transport layer endows the device with narrowband absorption in the SB region and optimized charge extraction capability from the CsPbI2Br perovskite. The optimized SHE exhibits a peak transmittance of 27% at 255 nm and a half maximum at full width of 28 nm. Under SB light illumination, the champion device achieves a responsivity of 56.20 mA W−1 and a detectivity (D*) of 2.86 × 1013 Jones, which are the record values among the reported results. The approach demonstrated here paves the way for the optical and electrical design of perovskite photodetectors with spectrally selective detection. [ABSTRACT FROM AUTHOR]

Semitransparent organic solar cells (STOSCs) hold great promise for applications ranging from building‐integrated photovoltaics to portable electronic devices, yet often challenging over the realization of color tunability. The structural colors generated by microcavity, subwavelength grating, or photonic crystals are highly dependent on the viewing angle, which limits the application of STOSCs in real scenarios. Herein, the spectrally selective substrates consisting of silica spheres‐based amorphous photonic crystals (APCs) are proposed to unify the optical spectra of STOSCs at different viewing angles. By optimizing the periodicity of APCs, STOSCs exhibit viewing‐angle‐independent reflection with colors varying from blue to pink. The synergetic interplay between the reflection of APCs and the absorption of active layer results in the Janus optical effect that the transmitted light is fixed at blue regardless of the reflected color. The STOSCs on flexible plastic retain the stable color even at bending state. These results pave the way for the potential application of colorful solar photovoltaic glass curtains. [ABSTRACT FROM AUTHOR]

Using narrow bandgap nonfullerene acceptors (NFAs) can broaden the absorption spectrum of organic solar cells (OSCs) to the near‐infrared region. However, the simultaneously decreased extinction coefficient of the active layer at the blue region results in inevitable light escaping and energy loss. Herein, a blazed grating‐based device configuration consisting of a patterned rear electrode is employed to compensate for the low absorption of nonfullerene OSCs. Experimental results reveal that the normal incidence light, especially blue light, that bounces off the patterned rear electrode is concentrated in a large tilted angle and subsequently trapped in waveguide mode. Along with the excitation of surface plasmon polariton, the structured nonfullerene OSCs using a new‐designed PM6:M36 active layer obtain the broadband absorption enhancement with 1.5 times increase at the blue region. The optimized device achieves an 8.95% increase in photocurrent and a champion power conversion efficiency of approaching 18%, which is the highest reported value among all the devices based on A‐D‐A type NFAs. [ABSTRACT FROM AUTHOR]

All-inorganic perovskite cesium lead iodide/bromide (CsPbI 2 Br) is considered as a robust absorber for perovskite solar cells (PSCs) because of its excellent thermal stability that guarantees its long-term operation stability. Efficient CsPbI 2 Br PSCs are available when obtaining low energy loss, which needs efficient charge generation, less charge recombination, and balanced charge extraction. However, numerous traps in perovskites hinder the photon-electron conversion process. Herein, hierarchical manipulation of charge recombination is proposed for CsPbI 2 Br PSCs featuring low energy loss. Nonselective trap reduction and selective halogen vacancy passivation are performed using 2,2'-(ethylenedioxy)diethylamine and phenylbutylammonium iodide for the bottom and top contacts, respectively. Because of all-around suppressed charge recombination, balanced charge extraction and suppressed hysteresis are realized. The champion PSC achieves an open-circuit voltage of 1.30 eV, a fill factor of 80.2%, and a power conversion efficiency of 16.6% that is 28.6% higher than that of the reference device. Moreover, the thermostability of PSCs is simultaneously enhanced because of the limited defect-assisted degradation.

Objective: To study the protective effect of intensive insulin treatment on cardiac myocytes of severely scalded rats., Methods: Eighteen model Sprague-Dawley (SD) rats were subjected to 30% total body surface area (TBSA) full thickness injury, and they were divided into three groups with 6 rats in each group. The right jugular vein was cannulated for fluid resuscitation and administration of drugs. The rats in burn group were injected with normal saline, the intensive insulin group with injection of insulin to maintain plasma glucose content in normal range, and the sham burn group received physiologic dose of saline without burn injury. Plasma glucose was monitored after burn injury. Rats were sacrificed at 6 hours postburn to examine plasma myocardial enzymes spectrum as well as histological and ultrastructure changes in cardiac tissue. The expression of p-Akt was detected by western blotting., Results: Plasma glucose level was significantly elevated in burn group within postburn 6 hours as compared with the sham burn group, and lowered in intensive insulin group (4.5 approximately 5.2 mmol/L vs. 7.6 approximately 8.4 mmol/L, P<0.05 or P<0.01). And the intensive insulin therapy could effectively inhibit the release of cardiac enzymes [lactate dehydrogenase (LDH): (2 369.3+/- 178.9) U/L vs. (2 684.1+/-335.0) U/L, P<0.05; alpha-hydroxybutyrate dehydrogenase (alpha-HBD): (576.7+/-219.2) U/L vs. (1 002.0+/-347.1) U/L, P<0.01; creatine kinase (CK): (1 041.9+/-623.2) U/L vs. (2 447.1+/-1 183.7) U/L, P<0.01]. The expression of p-Akt was significantly strengthened in the intensive insulin group (1.18+/-0.43 vs. 0.24+/-0.11, P<0.01). Light microscopic and electron microscopic examinations showed that intensive insulin therapy could alleviate the injury to myocardial cells and structural changes., Conclusion: Intensive insulin treatment possesses protective effect on cardiomyocytes after a severe burn, and it is related to its up-regulation of phosphorylation level of Akt in cardiomyocyte, thus inhibiting the damage to myocytes.