Skin-touch-actuated textile-based triboelectric nanogenerator with black phosphorus for durable biomechanical energy harvesting

Abstract

Textiles that are capable of harvesting biomechanical energy via triboelectric effects are of interest for self-powered wearable electronics. Fabrication of conformable and durable textiles with high triboelectric outputs remains challenging. Here we propose a washable skin-touch-actuated textile-based triboelectric nanogenerator for harvesting mechanical energy from both voluntary and involuntary body motions. Black phosphorus encapsulated with hydrophobic cellulose oleoyl ester nanoparticles serves as a synergetic electron-trapping coating, rendering a textile nanogenerator with long-term reliability and high triboelectricity regardless of various extreme deformations, severe washing, and extended environmental exposure. Considerably high output (~250–880 V, ~0.48–1.1 µA cm−2) can be attained upon touching by hand with a small force (~5 N) and low frequency (~4 Hz), which can power light-emitting diodes and a digital watch. This conformable all-textile-nanogenerator is incorporable onto cloths/skin to capture the low output of 60 V from subtle involuntary friction with skin, well suited for users’ motion or daily operations.

Hybrid Smart Fiber with Spontaneous Self‐Charging Mechanism for Sustainable Wearable Electronics

“…Potential and current curves are also shown in Figures S7 and S8 in the Supporting Information. The enhanced peak‐to‐peak power at higher frequency is attributed to generation of sufficient triboelectric charges by the continuous electrification of the active material . Output power of the hybrid smart fiber at 30 Hz was enough to continuously turn on six green light‐emitting diodes connected in series (inset of Figure c).…”

“…In this regard, energy harvesting technology enables to address continuous power supply, ensuring sustainability of wearable devices . In particular, triboelectric nanogenerators (TENGs) have attracted tremendous attention as sustainable power supply due to their versatility, such as availability in a variety of forms and ability to harness different kinds of mechanical energy .…”

“…In particular, triboelectric nanogenerators (TENGs) have attracted tremendous attention as sustainable power supply due to their versatility, such as availability in a variety of forms and ability to harness different kinds of mechanical energy . Recently, fiber/textile‐based TENGs demonstrated outstanding energy harvesting performance and were integrated with energy storage devices to realize a self‐charging energy unit for wearable electronics . However, to date, an integration of a TENG and an energy storage unit was accomplished through an additional electric circuit/connection for larger scale textile electronics .…”

Recent progress on flexible nanogenerators toward self‐powered systems

“…2 Thus, from the material point of view, the electron affinity, surface function groups, as well as work function are important factors affecting the output performance of TENG. A vast number of advanced materials have been explored, including graphene, [106][107][108][109] MXenes, 110,111 hydrogels, 112-115 aerogels, [116][117][118] black phosphorus (BP), 119 etc.…”

“…In addition, other materials are also reported as the various choices of tribo‐materials or electrodes for TENG application. For example, cashmere‐based TENG, modified textile‐based TENG by BP, and cellulose‐derived hydrophobic nanoparticles (Figure F), wrinkled PEDOT: PSS film, ultrathin paper‐based self‐powered system, patterned Ag nanofiber electrodes, and so forth. A summary of the output characteristics of TENGs based on various materials was listed in Table .…”