Triboelectric Nanogenerator Based on Copper Foam with Graded Porous Architectures for Energy Harvesting and Human Motion Monitoring

Abstract

With the rising development of the Internet of Things (IoTs) and artificial intelligence, triboelectric nanogenerators (TENGs) have shown great application potential to dramatically improve our daily lives as self-powered sensors in portable and wearable electronics. In this study, copper foam with graded porous architectures (CFGA), featuring interconnected micro- and nanoporous composite structures, has been developed via a cost-effective and convenient industrial strategy, including electro galvanizing, thermal diffusion, and corrosion methods in sequence. Based on the measurement and evaluation of compressed force, frequency, and reliability, the obtained CFGA can enlarge the contact surface areas and improve the output performance of TENG effectively as a positive electrode. The results show that TENG based on CFGA can yield an open-circuit voltage and a short circuit current of as high as 45.8 V and 1.88 μA, respectively. The corresponding maximum output peak power can reach ∼52.9 μW. For practical application, CFGA-TENG can be designed in a spacer-free structure for keyboards with the function of electronic code lock. Meanwhile, it can also be applied in smart shoe insoles as a self-powered CFGA-TENG sensor array for human motion monitoring in real time. Our work provides an industrial production approach for functional electronics as energy harvesters and sensors and makes it more accessible for practical applications.