Poly(dimethylsiloxane)/ZnO Nanoflakes/Three-Dimensional Graphene Heterostructures for High-Performance Flexible Energy Harvesters with Simultaneous Piezoelectric and Triboelectric Generation.

Herein, we report the successful synthesis of poly(dimethylsiloxane)/ZnO nanoflakes/three-dimensional graphene (PDMS/ZnO NFs/3D Gr) heterostructures using Ni foams as the template substrate via a facile route, while adapting a rational material design for a high-performance energy-harvester application. The PDMS/ZnO NFs/3D Gr heterostructure-based hybrid energy harvester simultaneously exploits the piezoelectric effect and triboelectrification and shows peak-to-peak output voltages up to 122 V and peak-to-peak current densities up to 51 μA cm-2, resulting in an ultrahigh power density of 6.22 mW cm-2. Furthermore, we have evaluated the performance of the PDMS/ZnO NFs/3D Gr heterostructure-based hybrid energy harvester by demonstrating its capacity to instantaneously power up 68 commercially available light-emitting diodes without the need for an additional energy-storage device. The excellent performance of these energy harvesters suggests that PDMS/ZnO NFs/3D Gr heterostructures present a viable strategy for the development of high-performance, flexible, wearable energy-harvesting devices.