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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