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Organic-inorganic halide perovskite quantum dots (PQDs) constitute an attractive class of materials for many optoelectronic applications. However, their charge transport properties are inferior to materials like graphene. On the other hand, the charge generation efficiency of graphene is too low to be used in many optoelectronic applications. Here, we demonstrate the development of ultrathin phototransistors and photonic synapses using a graphene-PQD (G-PQD) superstructure prepared by growing PQDs directly from a graphene lattice. We show that the G-PQDs superstructure synchronizes efficient charge generation and transport on a single platform. G-PQD phototransistors exhibit excellent responsivity of 1.4 × 10 8 AW –1 and specific detectivity of 4.72 × 10 15 Jones at 430 nm. Moreover, the light-assisted memory effect of these superstructures enables photonic synaptic behavior, where neuromorphic computing is demonstrated by facial recognition with the assistance of machine learning. We anticipate that the G-PQD superstructures will bolster new directions in the development of highly efficient optoelectronic devices. 

Abstract The current electric vehicles (EVs) face many challenges like limited charge capacity, low miles/charge, and long charging times. Herein, these issues are addressed by developing a dual‐function supercapacitor‐based energy‐storing carbon fiber reinforced polymer (e‐CFRP) that can store electrical energy and function as the structural component for the EV's body shell. This is achieved by developing a unique design, vertically aligned graphene sheets attached to carbon fiber electrodes on which different metal oxides are deposited to obtain high‐energy density electrodes. A high‐strength multilayer e‐CFRP assembly is fabricated using an alternate layer patterning configuration of epoxy and polyacrylamide gel electrolyte. The e‐CFRP so developed delivers a high areal energy density of 0.31 mWh cm^–2at 0.3 mm thickness and a high tensile strength of 518 MPa, bending strength of 477 MPa, and impact strength of 2666 J m^–1. To show its application in EVs, a toy car's body panel is fabricated with e‐CFRP and the toy car is able to operate using the energy stored in its frame. Moreover, when integrated with a solar cell, this composite powers an Internet of Things device, showing its feasibility in communication satellites.