Environmentally Friendly Silk Fibroin/Polyethyleneimine High-Performance Triboelectric Nanogenerator for Energy Harvesting and Self-Powered Sensing

Abstract

Due to the large emissions of greenhouse gases from the burning of fossil fuels and people’s demand for green materials and energy, the development of environmentally friendly triboelectric nanogenerators (TENGs) is becoming increasingly significant. Silk fibroin (SF) is considered an ideal biopolymer candidate for fabricating green TENGs due to its biodegradability and renewability. However, its intrinsic brittleness and relatively weak triboelectric performance severely limit its practical applications. In this study, SF was physically blended with poly(ethylenimine) (PEI), a polymer rich in amino groups, to fabricate SF/PEI composite films. The resulting films were employed as tribopositive layers and paired with a poly(tetrafluoroethylene) (PTFE) tribonegative layer to assemble high-performance TENGs. Experimental results revealed that the incorporation of PEI markedly enhanced the flexibility and electron-donating capability of composite films. By optimizing the material composition, the SF/PEI-based TENG achieved an open-circuit voltage as high as 275 V and a short-circuit current of 850 nA, with a maximum output power density of 13.68 μW/cm². Application tests demonstrated that the device could serve as an efficient self-powered energy source, capable of lighting up 66 LEDs effortlessly through simple hand tapping and driving small electronic components such as timers. In addition, the device can function as a highly sensitive self-powered sensor, capable of generating rapid and distinguishable electrical responses to various human motions. This work not only provides an effective strategy to overcome the intrinsic limitations of SF-based materials but also opens up new avenues for the development of high-performance and environmentally friendly technologies for energy harvesting and sensing.

1. Introduction

The continued use of fossil fuels not only hinders the progress of global carbon neutrality goals but also causes severe environmental pollution [1,2,3,4,5]. In the face of this challenge, green energy with renewable properties has attracted great attention [6,7]. The triboelectric nanogenerator (TENG), an emerging and disruptive energy-harvesting technology based on the coupling of contact electrification and electrostatic induction effects [8,9], has attracted extensive attention in recent years. It can efficiently convert various forms of mechanical energy—such as wind energy [10,11,12], ocean wave energy [13,14], raindrop energy [15,16,17], and human motion energy [18,19,20,21]—into electrical energy, offering a novel approach for building distributed and sustainable energy systems [22,23]. Since Wang et al. [24] first proposed the core concept of TENGs in 2012, this technology has demonstrated tremendous potential in self-powered energy supply and intelligent sensing applications, owing to its high output performance, low cost, structural design flexibility, and environmental friendliness [25,26,27].

However, despite the rapid advancement of TENG technology, its large-scale practical application still faces a critical challenge: the core triboelectric layers of high-performance TENGs are predominantly fabricated from non-biodegradable synthetic polymers [28], such as poly(vinylidene fluoride) (PVDF) and its copolymers [29], poly(acrylonitrile) (PAN) [30], and poly(phenylene sulfide) (PPS) [31]. These materials tend to cause persistent environmental pollution at the end of their service life. Therefore, the exploration and development of environmentally friendly, green alternative materials have become a crucial breakthrough for promoting the sustainable advancement of TENG technology [32,33,34]. Among these efforts, the fabrication of triboelectric layers using naturally derived and biodegradable materials is regarded as an ideal strategy to mitigate environmental pollution at its source. For instance, Muhammad Saqib et al. [35] employed edible almond seed shells as the tribopositive material to develop a highly stable, flexible, and portable self-powered humidity sensor. Among various natural materials, silk fibroin (SF)—a natural animal protein extracted from silkworm silk—has attracted considerable attention owing to its excellent biocompatibility, complete biodegradability, and abundant polar functional groups (such as hydroxyl, amino, and carboxyl groups) along its molecular chains [36,37]. These characteristics make SF an ideal green material consistent with the concept of full life-cycle environmental sustainability [38,39,40,41]. However, pristine SF films suffer from inherent drawbacks, including brittleness, poor flexibility, and weak intrinsic triboelectric performance, which severely limit their application in high-performance TENGs [42]. To overcome these limitations, various modification strategies have been explored. For example, Xiong et al. [43] employed carbon nanotube arrays (CNTAs) coated with SF to significantly increase the specific surface area of the triboelectric layer, thereby enhancing its triboelectric output performance. Another effective approach involves the incorporation of SF with selected synthetic green polymers to achieve synergistic enhancement of mechanical and electrical properties. For instance, the incorporation of poly(ethylenimine) (PEI) into sodium carboxymethyl cellulose not only enhances the triboelectric performance of the material but also significantly improves its flexibility [44]. Therefore, doping natural green materials with selected synthetic polymers can effectively overcome the inherent limitations of natural materials. PEI, a polymer rich in amino groups, possesses a high density of positive charges and strong electron-donating capability, offering a promising strategy for the modification of natural materials [45,46].

Based on the analysis above, this study aims to introduce PEI into the SF matrix through a simple and efficient physical blending strategy to synergistically overcome the brittleness of SF and enhance its triboelectric performance. We hypothesize that the amino groups in PEI can not only form hydrogen bonds or electrostatic interactions with SF molecular chains, thereby improving the flexibility and structural stability of the films, but also significantly increase the electron-donating ability and charge-trapping density on the surface of the composite material. To this end, SF/PEI composite films with varying ratios were systematically prepared and employed as the tribopositive layers, paired with commercial PTFE as the tribonegative layer to assemble TENGs. A series of characterization techniques, including scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), were used to investigate the effects of PEI incorporation on the microstructure of SF. The electrical output performance of the TENGs was comprehensively evaluated. Finally, the practical potential of the device was successfully demonstrated, both as a self-powered energy source (e.g., lighting LEDs and powering electronic devices) and as a self-powered sensor for monitoring various human motions. This work provides a novel solution for the development of high-performance, environmentally friendly energy harvesting and sensing technologies.

2. Materials and Methods

2.1. Materials

Natural silk was purchased from Jiangsu Province, China. Sodium carbonate (Na₂CO₃, AR) and lithium bromide (LiBr, AR) were purchased from Shanghai Macklin Biochemical Technology Co., Ltd., Shanghai, China. poly(ethylenimine) (PEI, branched, Mw ≈ 600) was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., Shanghai, China. poly(tetrafluoroethylene) (PTFE, thickness 0.1 mm) was purchased from Anheda Plastic Products Co., Ltd., Shenzhen, China, and poly(ethylene terephthalate) (PET, thickness 0.1 mm) was purchased from Dongguan Jubang Plastic Materials Co., Ltd., Dongguan, China. Copper foil (thickness 0.1 mm) was purchased from Dongguan Chuanggao Electronic Materials Co., Ltd., Dongguan, China. All water used in the experiments was deionized water.

2.2. Preparation of Silk Fibroin Solution

The preparation of the SF solution referred to the classic method previously reported by our research group, with slight modifications. In brief, natural silk fibers were first placed in a 0.02 mol/L Na₂CO₃ aqueous solution and boiled for 30 min to remove the sericin on the surface of the silk. This process was repeated three times, after which the fibers were rinsed with deionized water and dried in an oven at 60 °C until a constant weight was reached. Then, 10 g of dried silk fibers were added to 40 mL of 9.3 mol/L LiBr solution and were dissolved at 60 °C for 4 h until fully dissolved. The resulting solution was transferred into a dialysis bag (molecular weight cutoff: 8000–14,000 Da) and dialyzed in deionized water for 72 h, with the external dialysis water changed every 4 h to thoroughly remove LiBr and small molecular impurities. The dialyzed SF solution was centrifuged at 8000 rpm for 25 min, and the supernatant was collected to obtain an SF stock solution with a concentration of approximately 4 wt%, which was stored at 4 °C for later use.

2.3. Preparation of SF Films and SF/PEI Composite Films

2.3.1. Preparation of SF Film

The above SF stock solution was diluted with deionized water to prepare SF solutions with mass fractions of 1.0 wt%, 2.0 wt%, and 3.0 wt%, and was allowed to stand for 48 h to remove bubbles before use. 10 mL of the SF solution (of the specified concentration) was measured, poured into molds, and dried in a 60 °C oven in the same way, resulting in SF films. The films were then peeled off and stored in sample bags for later use.

2.3.2. Preparation of SF/PEI Composite Films

The prepared SF solution with a mass fraction of 2.0 wt% and the PEI solution with a mass fraction of 5.0 wt% were added to a beaker in different mass ratios (9:1, 8:2, 7:3, 6:4, 5:5) and homogenized for 20 min. Then, 10 mL of the mixed solution was measured and poured into molds, dried in a 60 °C oven in the same way, resulting in SF/PEI composite films. The films were peeled off and placed into sample bags for later use. According to measurements, the thickness of the SF/PEI film is 0.01 mm.

2.4. Assembly of TENG Devices

The prepared SF/PEI composite film, PTFE film, PET substrate, and copper foil were all cut into rectangles measuring 2.0 cm × 2.5 cm. The SF/PEI film served as the tribopositive layer and the PTFE film as the tribonegative layer, each adhered to self-adhesive conductive copper foil. A PDMS elastomer was used as the support, and PET as the substrate to assemble the TENG.

2.5. Characterization and Measurement

The surface morphology of SF and SF/PEI films was observed using a scanning electron microscope (SEM, HITACHI-SU8600, Hitachi, Tokyo, Japan). All samples were gold-sputtered prior to imaging to enhance their conductivity. Infrared absorption spectra of the samples were collected in the range of 500–4000 cm⁻¹ using a Fourier Transform Infrared Spectrometer (FTIR, BRUKER, Ettlingen, Germany). The crystalline structure of the samples was analyzed using X-ray diffraction (XRD, BRUKER). The elemental composition and chemical states of the surfaces of SF and SF/PEI films were analyzed using X-ray photoelectron spectroscopy (XPS, Thermo Fisher, Waltham, MA, USA). The electrical output performance of the TENG, including open-circuit voltage (Voc) and short-circuit current (Isc), was measured using a 6514 electrometer (Keithley, Cleveland, OH, USA). All mechanical stimuli were provided by a ST600C multimodal testing system (Suzhou Shengtai Intelligent Technology, Suzhou, China) to ensure controllability and reproducibility of contact frequency and force.

3. Results and Discussion

3.1. Design and Working Mechanism of SF/PEI-TENG

To overcome the dual challenges of high brittleness and insufficient triboelectric performance faced by pure silk fibroin (SF) materials in triboelectric nanogenerator applications, this study implemented a rational material design strategy: namely, the physical blending modification of SF with branched poly(ethylenimine) (PEI). The core of this design lies in the synergistic utilization of PEI’s dual functions: first, the amino groups abundant in PEI chains can form extensive hydrogen-bonding networks with the carbonyl, hydroxyl, and other groups on the SF molecular backbone, thereby acting as a ‘molecular toughening agent’ to effectively improve the flexibility and mechanical stability of the composite film; second, PEI itself, as a strong electron donor, has a high density of amino groups that can significantly enhance the electron-donating capability of the composite material, aiming to improve its charge output density and efficiency as a triboelectric positive electrode.

Based on the above design, we successfully prepared SF/PEI composite films and used them as the tribopositive layer, which, combined with a commercial poly(tetrafluoroethylene) (PTFE) negative electrode, was assembled into a typical contact–separation type TENG (SF/PEI-TENG), as shown in Figure 1a. The working mechanism of SF/PEI-TENG is based on the coupled effect of triboelectrification and electrostatic induction, and a complete working cycle can be divided into four stages (as shown in Figure 1b). Initial contact: Under external force, the SF/PEI film fully contacts the PTFE film at the interface. Due to the difference in electron affinity between the two, electrons transfer from the electron-donor SF/PEI layer to the electron-acceptor PTFE layer, resulting in a net positive charge on the SF/PEI interface and an equal net negative charge on the PTFE interface. Separation process: As the external force is removed, the two films separate from each other, generating a potential difference in the gap. To balance this potential, electrons flow through the external circuit from the electrode on the PTFE side to the electrode on the SF/PEI side, producing a transient forward current. Maximum separation: When the gap reaches its maximum, the system is in electrostatic equilibrium, and no current flows through the external circuit. Re-contact: When the external force is reapplied, bringing the two films close again, the potential difference decreases, driving electrons to flow in the opposite direction and generating a transient reverse current.

Through this periodic contact–separation, mechanical energy is continuously converted into pulsed electrical signals. The SF/PEI composite film consistently exhibits positive charge during cycling, preliminarily confirming the feasibility of this design. The above working mechanism indicates that the ultimate output performance of TENG is fundamentally determined by the physicochemical properties of the friction layer materials. Therefore, subsequent work first analyzed the regulatory effect of PEI introduction on the microstructure and chemical state of the SF film through systematic material characterization and then explored in detail its electrical output performance and practical application potential.

3.2. Microscopic Morphology and Structural Characterization of SF/PEI Films

The microscopic morphology and chemical structure of friction layer materials are key factors determining their triboelectric performance [47,48]. To investigate the effect of introducing PEI on the structural regulation of SF films, we first observed a series of samples using scanning electron microscopy (SEM). As shown in Figure 2a,d, the surface of pure SF films exhibits a smooth, dense, and uniform morphology. When SF and PEI were blended at a mass ratio of 9:1 (Figure 2b,e), irregular clustered protrusions began to appear on the surface, indicating that the addition of PEI disrupted the orderly arrangement of SF molecular chains and successfully constructed a micro-nano-scale rough structure. Figure S1 presents Figure 2b,e processed using ImageJ software. Notably, when the mass ratio of SF to PEI reached 6:4 (Figure 2g,h), the clustered structures on the film surface are the densest, and the roughness reaches its maximum, suggesting that it may provide the largest effective contact area, thereby significantly enhancing triboelectric output [49]. Figure S2 presents Figure 2g,h processed using ImageJ software. However, when the PEI ratio further increases to 5:5 (Figure 2c,f), excessive PEI may lead to more complex aggregation of molecular chains or the formation of a relatively continuous phase state, resulting in a decrease in surface roughness. Additionally, the cross-section of the SF/PEI (5:5) film shown in Figure 2i exhibits an orderly fibrous structure, demonstrating that PEI and SF form an interwoven, interconnected composite network in three-dimensional space.

In order to elucidate the interaction between PEI and SF at the molecular level, Fourier Transform Infrared Spectroscopy (FTIR) was employed for analysis. As shown in Figure 3a, compared with pure SF, the SF/PEI composite film exhibits a significantly broadened absorption peak in the 3000–3600 cm⁻¹ range, which is attributed to the overlapping stretching vibrations of O-H and N-H bonds, indicating the formation of an extensive hydrogen bonding network between the amine groups of PEI and the hydroxyl/amine groups of SF. In the 2800–3000 cm⁻¹ region, the intensity of the C-H stretching vibration peak in the SF/PEI film is enhanced, originating from the contributions of the alkyl segments in the PEI molecular chain. The characteristic peaks of C-N-C skeletal vibrations appearing in the 1000–1300 cm⁻¹ range further confirm the successful incorporation of PEI into the SF matrix.

The crystallization behavior of materials can be studied through X-ray diffraction (XRD), and the results are shown in Figure 3b. The pure SF film exhibits a broad diffuse peak at 2θ ≈ 20°, characteristic of an amorphous or Silk I structure. After the introduction of PEI, the XRD pattern of the SF/PEI (6:4) composite film does not show any sharp new diffraction peaks, indicating that it remains predominantly amorphous. However, the diffraction intensity in the low-angle region (around 2θ ≈ 10°) is significantly enhanced, suggesting that the addition of PEI may induce SF molecular chains to form more ordered structures or some intermediate state between Silk I and Silk II. This structure, mainly amorphous with locally increased order, was beneficial for providing abundant charge trapping sites during friction, while the inherent conductivity of PEI may facilitate charge dissipation, which requires finding a balance in subsequent performance tests.

The elemental composition and chemical states of the film surface were analyzed using X-ray photoelectron spectroscopy (XPS). As shown in Figure 3c, the N1s (~399.5 eV) spectra exhibited significant changes before and after the addition of PEI. Due to the amine-rich nature of PEI, the N1s peak in the SF/PEI spectrum is significantly enhanced compared to that in the SF spectrum, directly confirming the successful incorporation of PEI (rich in amine groups) onto the film surface. Figure 3d shows the C spectrum of the pure SF film, where very weak C-N (~285.5 eV) and N-C=O (~288.0 eV) peaks can be fitted. In the SF/PEI film (Figure 3e), the peaks corresponding to C-N (~285.5 eV) and N-C=O (~288.2 eV) are significantly enhanced; the former originates from the abundant C-N bonds in PEI, while the latter may be related to the formation of amide bonds or strong electrostatic interactions between the amine groups of PEI and the carboxyl/carbonyl groups of SF. These results collectively confirm the presence of strong intermolecular interactions between PEI and SF; this not only improves the mechanical properties of the film but, more importantly, enhances the polarity of the material surface, likely promoting charge transfer during contact electrification and contributing to improved triboelectric output.

3.3. Output Performance Analysis of SF/PEI-TENG

In order to systematically evaluate the effect of material modification on the improvement of device performance, we conducted electrical output performance tests on TENGs prepared with different parameters. First, we investigated the effect of SF concentration on the output performance of pure SF-TENGs. As shown in Figure 4a,b, when the mass concentration of SF increased from 1.0 wt% to 2.0 wt%, the device’s open-circuit voltage (Voc) increased from 125 V to 270 V, and the short-circuit current (Isc) increased from 700 nA to 825 nA. This improvement in performance can be attributed to the fact that an appropriately increased concentration helps form a denser and more complete film, thereby providing a more effective contact electrification interface. However, when the SF concentration was further increased to 3.0 wt%, both the open-circuit voltage and short-circuit current showed a significant decline. This is mainly because the films formed at higher SF concentrations exhibit excessive viscoelasticity and softness. During the contact phase, the overly soft surface undergoes larger deformation, reducing the effective contact area; during the separation phase, the material’s viscoelasticity easily causes a ‘sticking’ effect, hindering the friction layer from separating quickly and completely, thereby suppressing the efficiency of charge transfer to the external circuit.

Considering that films prepared with a 2.0 wt% SF solution exhibited the best performance, we systematically studied the effect of the mass ratio of SF to PEI on the output performance of SF/PEI-TENG based on this concentration. As shown in Figure 4d,e, with the increase in PEI content (i.e., the SF:PEI ratio changing from 9:1 to 6:4), both Voc and Isc of the device showed a trend of first increasing and then decreasing, reaching their maximum values (~275 V, ~850 nA) at SF:PEI = 6:4. This optimal result is consistent with SEM observations (Section 3.2), which showed that the film surface roughness was greatest at this ratio, confirming the key role of increasing the effective contact area in enhancing output. The introduction of PEI, on one hand, increased the positive charge of the material due to its abundant amine groups; on the other hand, the interaction network formed between PEI and SF (as confirmed by FTIR and XPS) facilitated charge stabilization and storage. However, when excessive PEI was added (e.g., 5:5), its strong hydrophilicity exacerbated water absorption from the environment, creating pathways for charge leakage, reducing the charge retention capability, and thus leading to a decline in output performance.

Working frequency is a key parameter affecting the actual output power of TENG. This study tested the optimal device (SF:PEI = 6:4) responses at different frequencies (1–4 Hz). As shown in Figure 4c,f, with the increase in frequency, both Voc and Isc increased significantly (from approximately 100 V to 275 V, and from approximately 600 nA to 850 nA). This is mainly due to the increased number of contact–separation cycles per unit time, which accelerates the generation and accumulation rate of charges. It is worth noting that the growth of current tends to flatten at higher frequencies, which might be because the SF/PEI film surface is rich in polar functional groups that have a strong adsorption effect on charges; even under high-speed charge generation, some charges are confined to the material surface and cannot participate in the external circuit in time.

Finally, by connecting a variable load resistor, we measured the power output capability of the optimized SF/PEI-TENG. As shown in Figure 4g–i, as the load resistance increased from 1 kΩ to 1 GΩ, the output voltage rose approximately linearly, while the output current correspondingly decreased. According to the power calculation formulas (P = V²/R or P = I²R), the relationship between the instantaneous output power density of the device and the resistance was calculated (Figure 4i). When the external load resistance is 1 MΩ (with the voltage increasing to around 200 V and the current approximately 370 nA), the output power reaches its peak, with a maximum power density of 13.68 μW/cm². This curve clearly demonstrates the high internal resistance characteristic of the TENG and provides a key reference for impedance matching in specific application scenarios. The electrical performance tests of the above system fully demonstrate that, through rational material design and process optimization, the prepared SF/PEI-TENG has the potential to be applied in practical electronic devices.

3.4. Performance Verification as a Self-Powered Power Source

The aforementioned results indicate that the SF/PEI-TENG can generate high pulsed alternating current (AC). However, most commercial electronic components require stable direct current (DC) for operation. Therefore, to realize its potential as a practical micro-power source, we introduced a bridge rectifier circuit to convert the AC output generated by the TENG into DC, with the equivalent circuit shown in Figure 5a. To visually demonstrate its instantaneous power output capability, we connected the rectified output to a set of 66 green light-emitting diodes (LEDs) in series. Figure 5b shows that tapping the TENG by hand can easily light up 66 green LEDs, strongly demonstrating the device’s high output performance capable of driving multiple miniature electronic devices.

Furthermore, we evaluated its capability to charge energy storage units and provide continuous power. As shown in Figure 5c, through continuous mechanical stimulation, the SF/PEI-TENG charged a commercial capacitor to 2 V, and the stored electrical energy successfully powered an electronic timer to resume normal operation. This experiment simulated a real scenario of powering low-power electronic devices, demonstrating the application value of the SF/PEI-TENG in managing intermittent mechanical energy and converting it into a stable power source.

For practical applications, the long-term operational stability of the device is crucial. To this end, we conducted a continuous contact–separation cycling test over 7 days. As shown in Figure 5d, the output voltage of the device did not show any significant attenuation throughout the test period. This result demonstrates that the SF/PEI composite film possesses excellent mechanical durability and charge retention capability, ensuring the reliable performance of the TENG during long-term operation and providing key evidence for its practical application.

3.5. Human Mechanical Energy Harvesting Applications as Self-Powered Sensors

Thanks to its high output and rapid response characteristics, the TENG can efficiently convert mechanical stimuli into electrical signals, which demonstrates its great potential in the field of self-powered sensing [49,50]. Human activity is a common source of mechanical energy in the environment. To verify the feasibility of applying SF/PEI-TENG in this field, we installed it on different parts of the human body and systematically evaluated its sensing performance for various movement patterns.

First, we tested the device’s sensitivity to slight touches. As shown in Figure 6a, when a single finger tapped the TENG, a voltage signal of approximately 15 V was generated; when two fingers were used, the signal amplitude increased to about 25 V. This positive correlation between signal strength and contact area clearly demonstrates the device’s ability to distinguish different touch intensities. Furthermore, the TENG was fixed on multiple joints of the human body to monitor more complex movements. When the device was installed on the arm and the arm naturally struck the leg (Figure 6b), the strong impact generated a voltage peak of up to 100 V. When the TENG was integrated into the sole of a shoe (Figure 6c), each step during brisk walking produced a stable pulse signal of ~80 V, clearly recording gait information. In addition, this study explored its ability to monitor joint bending angles. The TENG was worn on the wrist, and electrical output was measured at different bending angles (Figure 6d–f). The results showed that the output voltage monotonically increased with the wrist bending angle, rising significantly from ~1.5 V at 30° to ~30 V at 90°. This pronounced angle-signal dependency indicates that the device can accurately distinguish subtle variations in movement amplitude.

The results of the above series of experiments indicate that the SF/PEI-TENG can generate rapid, sensitive, and distinguishable electrical responses to various mechanical activities, ranging from slight human touches to large-scale joint movements, without the need for an external power source. This fully demonstrates its tremendous application potential as a self-powered sensor in fields such as human motion capture, medical rehabilitation monitoring, and intelligent wearable devices.

4. Conclusions

This study successfully introduced poly(ethylenimine) (PEI) into a silk fibroin (SF) matrix via a simple physical blending method to construct an environmentally friendly, high-performance triboelectric nanogenerator (SF/PEI-TENG). Systematic material characterization confirms that the introduction of PEI, through interactions such as hydrogen bonding with the SF molecular chains, effectively improved the film’s flexibility and significantly enhanced its surface electron-donating capability and charge storage properties. By optimizing the SF solution concentration and the SF/PEI mass ratio, the device exhibited the best electrical output performance at an SF:PEI ratio of 6:4, achieving an open-circuit voltage of 275 V and a short-circuit current of 850 nA, with a maximum power density of 13.68 μW/cm². This device can serve as an efficient micro-energy source, instantly lighting up 66 LEDs under mechanical stimulation and powering a commercial timer using stored energy, demonstrating excellent energy harvesting and conversion capabilities. Additionally, TENG shows high sensitivity and rapid response in human motion monitoring, effectively distinguishing mechanical signals of different intensities and showing broad application prospects in self-powered sensing. This work not only provides an effective strategy to address the brittleness and low triboelectric output issues of natural polymer materials in energy harvesting applications but also offers a new material system and design concept for developing the next generation of green, flexible electronic devices.