Key Takeaways & Executive Findings
- •• A system-level strategy is presented to achieve high charging efficiency in triboelectric nanogenerator (TENG)-supercapacitor (SC) hybrid devices, with a focus on frequency response design. • This study reveals that the high-frequency characteristics of SCs and the prolonged output pulse duration of TENGs are critical for achieving high charging efficiency. • A three-dimensional hollow-structured MXene is synthesized as a high-frequency SC electrode material, demonstrating a twofold increase in charging efficiency compared to conventional SCs. • The study highlights the importance of frequency response design in developing efficient chargeable TENG–SC hybrid devices.
Abstract
Energy harvesting storage hybrid devices have garnered considerable attention as self-rechargeable power sources for wireless and ubiquitous electronics. Triboelectric nanogenerators (TENGs), a common type of energy harvester, generate alternating current-based, irregular short pulses, posing a challenge for storing the generated electrical energy in energy storage systems that typically operate with direct current (DC)-based low-frequency response. In this study, we propose a new strategy that leverages high-frequency response to develop efficient chargeable TENG–supercapacitor (SC) hybrid devices. A high-frequency SC was fabricated using hollow-structured MXene electrode materials, resulting in a twofold increase in the charging efficiency of the hybrid device compared to a control SC made with conventional carbon electrode materials. For a systematic understanding, the electrochemical interplay between the TENGs and SCs was investigated as a function of the frequency characteristics of SCs (fSC) and the output pulse duration of TENGs (ΔtTENG). Increasing the fSC·ΔtTENG enhanced the charging efficiency of the TENG–SC hybrid devices. This study highlights the importance of frequency response design in developing efficient chargeable TENG–SC hybrid devices.
1. Introduction
The escalating proliferation of wireless and ubiquitous electronic devices has spurred the development of advanced energy harvesters to provide autonomous mobile power sources, eliminating the need for external electrical charging. Among the various energy harvesting technologies, triboelectric nanogenerators (TENGs) have attracted significant attention due to their high-output power, ease of manufacturing, environmental friendliness, and high energy conversion efficiency [1–11]. However, TENGs typically produce intermittent and low-power outputs (nW to μW) due to uncontrolled operating environments. Consequently, integrating TENGs with energy storage systems is essential to ensure a stable and sustainable power supply [7, 12–14].
Supercapacitors (SCs) have emerged as a promising energy storage system for integration with TENGs, attracting considerable interest due to their rapid charge/discharge capability, long cycle life, and simplicity in cell fabrication [15, 16]. Despite this interest, most previous studies on energy harvester–SC hybrid devices have primarily focused on enhancing TENG performance [17, 18], with limited attention given to the electrochemical interplay between TENGs and SCs. Since conventional SCs are primarily designed for direct current (DC) operations exhibiting low-frequency responses (<1 Hz), effectively storing the alternating current (AC)-based, irregular, and short-pulsed (i.e., high frequency of ~kHz) energy from TENGs poses a significant challenge. In such short-pulsed current scenarios, most SCs may behave more like resistors than capacitors, leading to unwanted energy loss during the energy conversion/storage process [19, 20]. To address these limitations, previous research has introduced electrical engineering-based solutions, such as power management circuits [7, 21–23] and DC-
Loading authentic research manuscript (Pages 1–5)...
Kwon-Hyung Lee, Min-Gyun Kim, Woosuk Kang, Hyun-Moon Park, Youngmin Cho, Jeongsoo Hong, Tae-Hee Kim, Seung-Hyeok Kim, Seok-Kyu Cho, Donghyeon Kang, Sang-Woo Kim, Changshin Jo, Sang-Young Lee (2025). Pulse-Charging Energy Storage for Triboelectric Nanogenerator Based on Frequency Modulation. Nano-Micro Letters. https://doi.org/10.1007/s40820-025-01714-3
Research & Educational Purpose Only:The translations, structured abstracts, analytical annotations, and data reports provided by SinoTechIntel are intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoTechIntel claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What is the main challenge in integrating TENGs with supercapacitors?
TENGs generate alternating current-based, irregular short pulses with high frequency (~kHz), while conventional supercapacitors are designed for direct current (DC) operations with low-frequency response (<1 Hz). This mismatch causes supercapacitors to behave like resistors, leading to energy loss during charging.
How does the proposed strategy improve charging efficiency?
The strategy leverages high-frequency response by using hollow-structured MXene as the supercapacitor electrode material, which enhances the frequency characteristics of the SC. This, combined with the prolonged output pulse duration of the TENG, increases the product fSC·ΔtTENG, thereby improving charging efficiency.
What is the significance of the fSC·ΔtTENG product?
The product of the frequency characteristics of the supercapacitor (fSC) and the output pulse duration of the TENG (ΔtTENG) is a key parameter that determines the charging efficiency of the hybrid device. Increasing this product enhances the efficiency, highlighting the importance of frequency response design.
What are the key findings of this study?
The study demonstrates that a high-frequency SC using hollow-structured MXene electrodes achieves a twofold increase in charging efficiency compared to conventional carbon-based SCs. It also reveals that both the high-frequency characteristics of SCs and the prolonged output pulse duration of TENGs are critical for efficient charging.
What is the potential application of this research?
This research provides a system-level strategy for developing efficient self-rechargeable power sources for wireless and ubiquitous electronics, which could lead to more reliable and sustainable energy harvesting and storage solutions.
Related Technical Papers & Translations
Direct Repair of the Crystal Structure and Coating Surface of Spent LiFePO4 Materials Enables Superfast Li-Ion Migration
The rapid accumulation of spent LiFePO4 (LFP) cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies. In this context, direct regeneration has emerged as a promising approach for reclaiming LFP cathode materials, offering a streamlined pathway to restore their electrochemical functionality. We report an integrated regeneration protocol that simultaneously repairs the degraded crystal structure and reconstructs the damaged carbon coating in spent LFP. The regenerated cathode material had superfast lithium-ion diffusion kinetics and a stable cathode–electrolyte interface, giving a remarkable rate capability with specific capacities of 122 mAh g−1 at 5C and 106 mAh g−1 at 10C (1C = 170 mA g−1). It also maintained capacities of 110.7 mAh g−1 (5C) and 84.1 mAh g−1 (10C) after 400 cycles. It could be used in harsh environments and could be stably cycled at subzero temperatures (−10 and −20 °C) and in solid-state electrolyte batteries. Life cycle assessment combined with economic evaluation using the EverBatt model reveals that this direct regeneration approach has high economic and environmental benefits.
Oxide Semiconductor for Advanced Memory Architectures: Atomic Layer Deposition, Key Requirement and Challenges
Oxide semiconductors (OSs), introduced by the Hosono group in the early 2000s, have evolved from display backplane materials to promising candidates for advanced memory and logic devices. The exceptionally low leakage current of OSs and compatibility with three-dimensional (3D) architectures have recently sparked renewed interest in their use in semiconductor applications. This review begins by exploring the unique material properties of OSs, which fundamentally originate from their distinct electronic band structure. Subsequently, we focus on atomic layer deposition (ALD), a core technique for growing excellent OS films, covering both basic and advanced processes compatible with 3D scaling. The basic surface reaction mechanisms—adsorption and reaction—and their roles in film growth are introduced. Furthermore, material design strategies, such as cation selection, crystallinity control, anion doping, and heterostructure engineering, are discussed. We also highlight challenges in memory applications, including contact resistance, hydrogen instability, and lack of p-type materials, and discuss the feasibility of ALD-grown OSs as potential solutions. Lastly, we provide an outlook on the role of ALD-grown OSs in memory technologies. This review bridges material fundamentals and device-level requirements, offering a comprehensive perspective on the potential of ALD-driven OSs for next-generation semiconductor memory devices.
Laser powder bed fusion of biodegradable Zn-4Cu alloy: Processing, microstructure and properties
Zn's natural degradability and biocompatibility make it a promising candidate for implants, however, its mechanical properties remain insufficient for bone applications. In this study, the performance of Zn was enhanced by developing Zn-Cu alloys via laser powder bed fusion (LPBF). Optimal LPBF parameters for forming stable tracks were achieved by adjusting laser power and scanning speed. Under optimized conditions of 100 W and 100 mm/s, high-density (99.58%) Zn-Cu alloys with improved hardness (68.2HV) and yield strength (160 MPa) were achieved. These improvements are attributed to solid solution strengthening, segregation strengthening, and grain refinement. The Zn-Cu alloys also demonstrated favorable degradation behavior, with a rate of 0.16 mm/year. This degradation is primarily driven by micro-galvanic corrosion between the CuZn5 phase and Zn matrix, along with refined grains and increased grain boundary density. This work demonstrates a viable strategy for fabricating Zn-based implants with enhanced structural integrity and mechanical performance via LPBF.