Polymer passivation layers can improve the open-circuit voltage of perovskite solar cells when inserted at the perovskite–charge transport layer interfaces. Unfortunately, many such layers are poor conductors, leading to a trade-off between passivation quality (voltage) and series resistance (fill factor, FF). Here, we introduce a nanopatterned electron transport layer that overcomes this trade-off by modifying the spatial distribution of the passivation layer to form nanoscale localized charge transport pathways through an otherwise passivated interface, thereby providing both effective passivation and excellent charge extraction. By combining the nanopatterned electron transport layer with a dopant-free hole transport layer, we achieved a certified power conversion efficiency of 21.6% for a 1-square-centimeter cell with FF of 0.839, and demonstrate an encapsulated cell that retains ~91.7% of its initial efficiency after 1000 hours of damp heat exposure.

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Textiles have proved to be very important materials to human beings since the time immemorial. And, fibers are the basic building units of these materials. In this perspective we substantiate the uniqueness and capability of nanofibers as active layers in face masks, to protect people against the novel coronavirus disease . This time-sensitive letter introduces the mechanisms based on which their active filters function, the uniqueness of electrospun nanofibers in face masks and do-it-yourself (DIY) steps to realize a fully functional face mask at home.

Designing aerogel materials featuring both high thermal insulation property and excellent mechanical robustness is of great interest for applications in superior integrated energy management systems. To meet the above requirements, composite aerogels based on hierarchical “stiff–soft” binary networks are reported, in which secondary mesoporous polymethylsilsesquioxane domains intertwined by bacterial cellulose nanofibrillar networks are connected in tandem. The resulting composite aerogels are characterized by highly porous (93.6%) and nanosized structure with a surface area of 660 m2 g−1, leading to the excellent thermal insulation performance with a low thermal conductivity of 15.3 mW m−1 K−1. The integrated “stiff–soft” binary nature also endows the composite aerogels with high flexibility that can conform to various substrates as well as large tensile strength that can withstand more than 2.70 × 104 times its own weight. These composite aerogels show multifunctionality in terms of efficient wearable protection, controllable thermal management, and ultrafast oil/water separation. These favorable multifeatures present composite aerogels ideal for aerospace, industrial, and commercial applications.

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