Through fabricating a perovskite/photoactive layer mixed light-harvester, the all-inorganic CsPbBr3 PSC achieved a champion PCE of 10.26% and excellent stability in high humidity or high temperature atmosphere.

The power conversion efficiency (PCE) of state‐of‐the‐art perovskite solar cells (PSCs) with mesoscopic titanium dioxide (TiO2) has rushed to 23.7% in recent years. However, photodegradation of perovskites under illumination (including ultraviolet light), assisted by TiO2, significantly reduces the long‐term stability of the corresponding device, which in turn limits the commercialization of PSCs. Owing to the advantages of high electron mobility, wide bandgap, high transparency, and good photostability, nanostructured tin oxide (SnO2) is demonstrated to be a more promising electron‐transporting material for planar PSCs. Herein, low‐temperature solution‐processed SnO2 quantum dots (QDs) are employed as the electron transport layer (ETL) for all‐inorganic cesium lead bromide (CsPbBr3) PSC applications. Through optimizing the aging time of SnO2 QDs and adding a hole transport layer (HTL) of CsMBr3 (M = Sn, Bi, Cu) QDs between the CsPbBr3 layer and carbon electrode, the all‐inorganic PSC with a structure of FTO/SnO2/CsPbBr3/CsMBr3/carbon achieves a good PCE of 10.60% with an ultrahigh open‐circuit voltage up to 1.610 V. These optimized devices, free of encapsulation, present excellent stability in 80% humidity or temperature of 80 °C. The maximized PCE report to date and improved environmental‐tolerance for all‐inorganic CsPbBr3 solar cells provide new opportunities to dramatically promote the commercialization of PSC platforms.

The crystal structure of cesium lead halide (CsPbX3, X = I, Br, Cl) determines its charge‐carrier trap state and solar‐to‐electrical conversion ability in inorganic perovskite solar cells (PSCs). Here, the compositional engineering of inorganic CsPbBr3 perovskite by means of doping with various alkali metal cations is studied. The lattice dimensions and energy levels of Cs1‐xRxPbBr3 (R = Li, Na, K, Rb, x = 0–1) halides are optimized by tuning Cs/R ratio. Arising from promoting effects of alkali metal cations doped perovskite halides such as lattice shrink, crystallized dynamics, and electrical‐energy distribution, a maximum power conversion efficiency as high as 9.86% is achieved for hole transporting layer‐free Cs0.91Rb0.09PbBr3 tailored solar cell owing to the suppressed non‐radiative losses and radiative recombination. Furthermore, the all‐inorganic Cs0.91Rb0.09PbBr3 solar cell without encapsulation remains 97% of initial efficiency when suffering persistent attack by 80% RH in air atmosphere over 700 h, which is in comparable with state‐of‐the‐art organic–inorganic hybrid and all‐inorganic PSC devices. Employing alkali metal cations to modulate perovskite layers provide new opportunities of making high‐performance inorganic PSC platforms.

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We propose a design for a highly sensitive biosensor based on nanostructured anodized aluminum oxide (AAO) substrates. A gold-deposited AAO substrate exhibits both optical interference and localized surface plasmon resonance (LSPR). In our sensor, application of these disparate optical properties overcomes problems of limited sensitivity, selectivity, and dynamic range seen in similar biosensors. We fabricated uniform periodic nanopore lattice AAO templates by two-step anodizing and assessed their suitability for application in biosensors by characterizing the change in optical response on addition of biomolecules to the AAO template. To determine the suitability of such structures for biosensing applications, we immobilized a layer of C-reactive protein (CRP) antibody on a gold coating atop an AAO template. We then applied a CRP antigen (Ag) atop the immobilized antibody (Ab) layer. The shift in reflectance is interpreted as being caused by the change in refractive index with membrane thickness. Our results confirm that our proposed AAO-based biosensor is highly selective toward detection of CRP antigen, and can measure a change in CRP antigen concentration of 1 fg/ml. This method can provide a simple, fast, and sensitive analysis for protein detection in real-time.