Nanowrinkle-patterned flexible woven triboelectric nanogenerator toward self-powered wearable electronics

Wearable triboelectric sensors for biomedical monitoring and human-machine interface

“…Because the separate surface area is linearly correlated to the bending angles, the amplitude of output voltage can directly reflect the bending state. This quantification based on amplitude has been adopted in many researches ( Alam et al., 2020 ; Han et al., 2019 ; Liu et al., 2020 ; Yu et al., 2019 ). As a demonstration, five such kind of sensors are attached on to the fingers to monitor the motion of each finger and different gestures.…”

Towards Truly Wearable Systems: Optimizing and Scaling Up Wearable Triboelectric Nanogenerators

“…Some of the woven fabric-based TENGs have been constructed using fabric structural modifications, which include woven pattern variations ( Chen et al., 2020 , 2018 ; Ma et al., 2020 ; Ning et al., 2018 ; Zhao et al., 2016a , 2016b ; Zhang et al., 2016 ), grated fabric structures ( Paosangthong et al., 2019b ; Pu et al., 2016b ), corrugated structures ( Choi et al., 2017 ), wrinkled structures ( Liu et al., 2020a , 2020b ) etc., which we discuss in this section. Such modifications are viable during weaving because two different yarn sets (warp and weft) are being interlaced.…”

“…Considering charge density improvements, selecting triboelectric materials further apart in the triboelectric series has been a major focus ( Chen et al., 2020 , 2018 ; Liu et al., 2020a , 2020b ; Lou et al., 2020 ; Ning et al., 2018 ; Pu et al., 2016b , 2016a ; Shi et al., 2017 ). Furthermore, physical and chemical modifications of triboelectric materials and contact surfaces have also been successfully implemented in this regard.…”

“…Furthermore, physical and chemical modifications of triboelectric materials and contact surfaces have also been successfully implemented in this regard. For instance, composite material structures have been used for fabric-based TENG developments, obtaining higher triboelectric charging ( Bai et al., 2019 ; Guo et al., 2020 ; Liu et al., 2020a , 2020b ). Similarly, constructing surface patterning on fabrics ( Choi et al., 2017 ; Huang et al., 2019 ; Paosangthong et al., 2019b ; Zhang et al., 2019 ) (e.g., grated or corrugated structures, reactive ion etching) and the use of nanomaterials and nanopatterning techniques to enhance triboelectric contact area ( Lee et al., 2015 ; Xiong et al., 2018 ) were successfully implemented to improve triboelectric charge density, thus enhancing TENG outputs.…”

“…There were wide expansions in the range of materials used in textile-based TENGs, including conventional and modified textile-related materials ( Chen et al., 2018 ; Choi et al., 2017 ; Gong et al., 2017 ; He et al., 2020 ; Ning et al., 2018 ; Shi et al, 2016 ; Song et al., 2017 ; Yao et al., 2017 ; Ye et al., 2020a ) and conductive polymers ( Dudem et al., 2019 ; Li et al., 2016 ), etc., along with improved application techniques such as enhanced coating methods ( Sala de Medeiros et al., 2019 ; Zhou et al., 2014a , 2014b ) and deposition techniques ( Choi et al., 2017 ; Huang et al., 2019 ; Paosangthong et al., 2019b ; Zhang et al., 2019 ; Zhou et al., 2014a , 2014b ), resulting in improved TENG performances. The structural developments of TENGs have also boosted TENG performances, which were obtained through various micro-fabrication techniques and textile manufacturing methods (e.g., weaving, Chen et al., 2020 , 2018 ; Liu et al., 2020a , 2020b ; Lou et al., 2020 ; Ning et al., 2018 ; Pu et al., 2016b , 2016a ; Shi et al., 2017 ; knitting, Dong et al., 2017b ; Huang et al., 2019 ; Kwak et al., 2017 ; nonwoven, Liu et al., 2018a , 2018b ; Peng et al., 2019 ; etc.). More recently, some TENG designs utilized cleverly designed hybridization of several textile manufacturing techniques, which include hybrid knitted/woven ( Yi et al., 2019 ) fabric structures and hybrid yarn/fabric-based structural modifications ( Liu et al., 2016 ), providing enhanced wearable and electrical functionalities compared with conventional devices.…”