A Flexible, Recyclable, and High‐Performance Pullulan‐Based Triboelectric Nanogenerator (TENG)

Abstract

interests on the material engineering, [10,11] structure modification, [12][13][14][15][16] and practical applications. [17][18][19][20][21] However, there are several limitations on biomedical and biowearable applications for TENGs due to the synthetic polymers and nonbiocompatibility of the majority ongoing TENGs. Thus, the natural biomaterialsbased TENGs [22] have immensely attracted the researcher's attentions with the merits of biocompatibility, low cost, and plentiful raw materials. [23][24][25] Wang et al. [24] reported a biodegradable and flexible chitosanbased TENG (chitosan was derived from chitin) and explored the feasibility of laser processing of constituent materials. Jiang et al. [25] developed various fully bioabsorbable natural-materials-based TENGs, which were used as an in vivo voltage source to accelerate the beating rates of dysfunctional cardiomyocyte clusters and improve the consistency of cell contractions. Generally, the natural biomaterials, prepared into bio-TENGs, are mainly divided into two strategies, including natural proteins and polysaccharides. [23] Therein, many other polysaccharides [26][27][28][29] with unique properties are supposed to be researched and optimized for the better electric performance and bioapplications of the bio-TENGs.Pullulan, produced by the yeast-like funguses, [30] is a linear and unbranched micro-organismal polysaccharide with maltotriose repeating units connected by α−(1 → 6) glycosidic bonds. [31] In the past several decades, pullulan and its derivatives have been widely applied in biomedical, [31] food, [32] pharmaceutical, [33] and petroleum industries [34,35] with the properties of nonmutagenicity, water solubility, editability, [36] nontoxicity, biodegradation, [37] biocompatibility, nonimmunogenicity, and noncarcinogenicity. To our knowledge, there is no research about TENGs or wearable devices fabricated with pullulan. Moreover, the excellent properties of pullulan make it possible to design and adjust the composite of the pullulan film, which is more suitable for TENGs and the biowearable devices. Here, we develop a flexible, recyclable, and highperformance pullulan-based TENG to harvest and transform mechanical energy into electric energy. The physical and chemical characterizations and output performance are investigated to optimize the composite and thickness of the pullulan-based TENGs. Then, the feasibility of the pullulan-based TENGs as the wearable device is explored. Finally, we investigate the recycling performance of the pullulan-based TENG, evaluated by the open-circuit voltage of the as-fabricated TENGs.The developments of natural biomaterials-based triboelectric nanogenerators (TENGs) have been emerged with the extensive and promising requirements in biomedical and biowearable fields due to the properties of renewability, cost-effectivity, biocompatibility, and biodegradability. In this work, a flexible, recyclable, and high-performance pullulan-based TENG, fabricated with pullulan and other additives, is developed. Based on the ope...

Polysaccharide-based triboelectric nanogenerators: A review

“…Lu, Li, Ping, He, & Wu (2020) investigated the performance and recyclability of a pullulan-based TENG, including various additives: glycerol, NaF, trehalose, bovine serum albumin (BSA) and carboxymethyl cellulose (CMC). A pullulan-pure and five pullulan-based films (64 cm 2 ) were prepared by mixing 7.5 ml (10 % wt) pullulan solution with 7.5 ml BSA, CMC, glycerol at 1 % wt or 0.1 M in the case of NaF and trehalose.…”

“…In this case, the first synthetic-based TENGs were mostly inserted in common shoes and are activated by the press and release motion while walking (Hou et al, 2013;Huang et al, 2014). Wearable and stretchable fabrics that induce triboelectric energy are another common approach to human motion harvesting (Kim et al, (Lu et al, 2020). Copyright (2020) with permission from Wiley-VCH.…”

“…a) vertical contact-separation mode scheme; b) open-circuit output voltages; c) summary of the voltage output at 10 Hz; d) summary of the voltage output at 10 W of loading power; e) output power at various loading resistances; f) recycling mechanisms of the pullulan film; g) summary of the open-circuit output voltage after various reuses; h) open-circuit voltage curves after various reuses. Reprinted from(Lu et al, 2020). Copyright (2020) with permission from Wiley-VCH.…”

Bio‐Derived Natural Materials Based Triboelectric Devices for Self‐Powered Ubiquitous Wearable and Implantable Intelligent Devices

“…[85][86][87][88] Recently, many bio-derived natural materials based triboelectric devices have been reported for in vitro and in vivo applications with excellent biocompatibility and biodegradability. [12,[88][89][90][91] The utilization of otherwise wasted natural materials for harvesting the wasted mechanical energy is of interest not only for fundamental scientific exploration but also for fibroin or silkworm cocoon exhibit good conductivity and excellent performance for energy storage and wearable electronics. [126][127][128][129][130][131][132][133] For example, Mao and co-workers [126] developed a high-performance textile electrode, using an in situ polymerization method to enhance the doping levels of the polypyrrole (PPy) molecule and provide a dense and thin conductive polymer coating on the fabric surface.…”

“…Bio-derived natural materials have gained increased interests for triboelectric applications because of their excellent mechanical property, biocompatibility, and biodegradability. [12,90,208,241,242] In this section, we will summarize the recent advances in bioderived natural materials based triboelectric devices for in vitro and in vivo applications.…”