Currently, it is still a significant challenge to simultaneously boost various reactions by one electrocatalyst with high activity, excellent durability, as well as low cost. Herein, hybrid trifunctional electrocatalysts are explored via a facile one‐pot strategy toward an efficient oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER). The catalysts are rationally designed to be composed by FeCo nanoparticles encapsuled in graphitic carbon films, Co2P nanoparticles, and N,P‐codoped carbon nanofiber networks. The FeCo nanoparticles and the synergistic effect from Co2P and FeCo nanoparticles make the dominant contributions to the ORR, OER, and HER activities, respectively. Their bifunctional activity parameter (∆E) for ORR and OER is low to 0.77 V, which is much smaller than those of most nonprecious metal catalysts ever reported, and comparable with state‐of‐the‐art Pt/C and RuO2 (0.78 V). Accordingly, the as‐assembled Zn–air battery exhibits a high power density of 154 mW cm−2 with a low charge–discharge voltage gap of 0.83 V (at 10 mA cm−2) and excellent stability. The as‐constructed overall water‐splitting cell achieves a current density of 10 mA cm−2 (at 1.68 V), which is comparable to the best reported trifunctional catalysts.

Inorganic lead halide perovskite has become an emerging material for modern photoelectric and electronic nanodevices due to its excellent optical and electronic properties. In view of its huge dielectric and electrical properties, inorganic CsPbBr3 perovskite is introduced into the piezoelectric nanogenerator (PENG). Based on one‐step electrospinning of solutions containing CsPbBr3 precursors and polyvinylidene difluoride (PVDF), in situ growth of CsPbBr3 nanocrystals in PVDF fibers (CsPbBr3@PVDF composite fibers) with highly uniform size and spatial distribution are synthesized. The CsPbBr3@PVDF composite fibers based PENG reveals an open‐circuit voltage (Voc) of 103 V and a density of short‐circuit current (Isc) of 170 µA cm−2, where the Voc is comparable to the state‐of‐the‐art hybrid composite piezoelectric nanogenerators (PENGs) and the density of Isc is 4.86 times higher than that of lead halide perovskites counterpart ever reported. Moreover, CsPbBr3@PVDF composite fibers based PENG exhibits fundamentally improved thermal/water/acid–base stabilities. This study suggests that the CsPbBr3@PVDF composite fiber is a good candidate for fabricating high‐performance PENGs, promising application potentials in mechanical energy harvesting and motion sensing technologies.

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Quasi‐2D CsPbI3 perovskites have emerged as excellent candidates for advanced photovoltaic technologies due to their fundamentally enhanced stability than conventional 3D counterparts. However, the applications of quasi‐2D perovskites are plagued with their poor out‐of‐plane carrier mobility induced by the intercalated insulating organic layers. In this work, a new strategy is explored to significantly enhance the out‐of‐plane charge transport in quasi‐2D Dion–Jacobson (DJ) CsPbI3 perovskites via leveraging the intercalation of aromatic diamine cations (p‐phenylenediamine, PPDA) with unique π‐conjugated bond based on the first‐principles calculations. The strong interactions between PPDA2+ cations and inorganic Pb‐I framework (i.e., I–I interaction, p‐π coupling, and H‐bonds) provide three carrier pathways to facilitate the out‐of‐plane charge transport. Furthermore, the restricted in‐plane and out‐of‐plane structural distortion induced by the π‐conjugated bond could improve the electronic coupling and charge mobility along the out‐of‐plane direction with reduced bandgaps. As a proof of concept, the calculated average photovoltaic conversion efficiency of such engineered DJ CsPbI3 perovskite solar cells is ≈17%, which is very close to the certificated champion efficiency of 3D α‐CsPbI3, underscoring their potential for solar cell applications.

Organic intercalation engineering of perovskites endows the as-constructed quasi-2D Dion–Jacobson α-CsPbI3 with a linearly aligned bandgap and fundamentally enhanced stability.

The electrode nearly full-featured for robust wide-temperature operation based on single-crystalline integrated 4H-SiC nanochannel arrays was explored.

We report the exploration of all-inorganic perovskite photodetectors based on stabilized CsPb0.922Sn0.078I3 nanobelts, which exhibit overall excellent performance with an ultrahigh detectivity up to 6.43 × 1013 Jones.

Even though two-dimensional (2D) perovskites have outstanding atmospheric durability, the quantum well (QW) structure of the materials considerably limit their photovoltaic efficiencies far below the three-dimensional (3D) analogues. Herein in this work, we adopt the ionic liquid (IL) 1butyl-3-methylimidazolium iodide (BMI) as an organic spacer in 2D perovskite to fundamentally alter the QW structures. In comparison to the traditional Ruddlesden−Popper (RP) type perovskites, the new RP-2D perovskite shows drastically decreased interlayer distance to 3.5 Å, which endows stronger interactions between the inorganic slabs and a weaker quantum confinement effect of the material. We further unveil that the combination of BM + and BA + cations enables a facile regulation of the excitonic structures and optical p r o p e r t i e s o f 2 D p e r o v s k i t e . B y t h i s d e s i g n , t h e h y b r i d (BM) 2−x (BA) x MA n−1 Pb n I 3n+1 based PSCs achieve an optimized PCE of 17.3%, which is among the highest reported values for 2D PSCs to date. Due to the outstanding heat resilience of IL, the PSCs also demonstrate extraordinary thermal stability under aging at 85 °C.