Recycled, Contaminated, Crumpled Aluminum Foil-Driven Triboelectric Nanogenerator.

With rapid urbanization and global population growth, the amount of wasted aluminum foil is significantly increasing. Most deformed and contaminated foil is difficult to recycle; hence, it is landfilled or incinerated, causing environmental pollution. Therefore, using aluminum foil waste for electricity may be conducive to addressing environmental problems. In this regard, various literatures have explored the concept of energy generation using foil, while a crumple ball design for this purpose has not been studied. Thus, a recycled foil-based crumpled ball triboelectric nanogenerator (RFCB-TENG) is proposed. The crumpled ball design can minimize the effects of contamination on foil, ensuring efficient power output. Moreover, owing to novel crumpled design, the RFCB-TENG has some outstanding characteristics to become a sustainable power source, such as ultralight weight, low noise, and high durability. By introducing the air-breakdown model, the RFCB-TENG achieved an output peak voltage of 648 V, a current of 8.1 mA cm3 , and an optimum power of 162.7 mW cm3 . The structure of the RFCB-TENG is systemically optimized depending on the design parameters to realize the optimum output performance. Finally, the RFCB-TENG operated 500 LEDs and 30-W commercial lamps. This work paves the guideline for effectively fabricating the TENG using waste-materials while exhibiting outstanding characteristics.

Ultrahigh Performance, Serially Stackable, Breeze Driven Triboelectric Generator via Ambient Air Ionizing Channel.

Currently, wind energy harvesting is in the limelight. However, with the existing electromagnetic wind generators, it is difficult to harvest multifariously-wasted breezes. To harvest energy from winds at a wide range of speeds, wind-driven triboelectric nanogenerators (TENGs) are studied. However, a critical limitation of general wind-driven TENGs is that their power output is low. Therefore, an innovative strategy is necessary to generate high output power even from breeze. Herein, an approach to test a charge-polarization-based flutter-driven TENG (CPF-TENG) with ambient air ionizing channel (AAIC) is reported. Owing to AAIC, the device generates peak voltage and current outputs of 2000 V and 4 A, respectively. Moreover, because the proposed CPF-TENG can generate power from breeze, it can be stacked in series to completely harvest wind energy. The stacked CPF-TENG is demonstrated to operate 3000 light-emitting diodes (LEDs) and 12 hygrometers, separately, and produce hydrogen at a rate of 342.3 µL h-1 with the electrolysis cell.

Lightweight mobile stick-type water-based triboelectric nanogenerator with amplified current for portable safety devices.

Due to its abundance, mechanical energy is a promising ambient energy source. Triboelectric nanogenerators (TENGs) represent an effective mechanical energy harvesting method based on the use of contact electrification. The existing liquid-based TENGs can operate robustly without surface damage; however, the output of these TENGs is considerably smaller than that of solid-based TENGs. Notably, liquid-based TENGs in which the liquid directly contacts the conductive material can produce an electrical current of more than few mA. However, the liquid reservoir must have an adequate volume, and sufficient space must be provided for the liquid to move for generating the electrical output. To ensure a compact and lightweight design and produce electrical output in the low input frequency range, we introduce a mobile stick-type water-based TENG (MSW-TENG). The proposed MSW-TENG can generate an open-circuit voltage and closed-circuit current of up to 710 V and 2.9 mA, respectively, and be utilized as self-powered safety device. The findings of this study can promote the implementation of TENGs in everyday applications.

Triangulated Cylinder Origami-Based Piezoelectric/Triboelectric Hybrid Generator to Harvest Coupled Axial and Rotational Motion.

Piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs) are representative technologies that can harvest mechanical energy. In general, piezoelectric/triboelectric hybrid generators can harvest considerable energy with a limited input; however, PENGs and TENGs entail different requirements for harvesting energy. Specifically, PENGs produce a large output when a large mechanical strain is applied, and TENGs require a large surface area to produce a high power. Therefore, it is necessary to develop an innovative strategy in terms of the structural design to satisfy the requirements of both PENGs and TENGs. In this study, we developed a triangulated cylinder origami-based piezoelectric/triboelectric hybrid generator (TCO-HG) with an origami structure to enable effective energy harvesting. The proposed structure consists of a vertical contact-separation TENG on the surface of the triangulated cylinder, PENG on the inner hinge, and rotational TENG on the top substrate to harvest mechanical energy from each motion. Each generator could produce a separate electrical output with a single input. The TCO-HG could charge a 22 µF commercial capacitor and power 60 LEDs when operated.