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    A Self-Powered and Chemically Responsive Triboelectric Nanogenerator Based on Surface Protonation in SrO2Nanopowder/Graphene Oxide/epoxy Composite for pH Sensing
    (2025-12-05)
    Saengpoe, Prasert
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    Supasai, Wisut
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    Amorntep, Narong
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    Nilnumpetch, Chatree
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    Nokkaew, Manussawee
    Practical implementation of triboelectric nanogenerators (TENGs) in autonomous systems is frequently impeded by their inadequate durability in chemically harsh environments. To address this limitation, we present a durable TENG utilizing a strontium dioxide nanopowders/graphene oxide/epoxy resin (SrO<inf>2</inf>NPOs/GO/ER) composite, positioning SrO<inf>2</inf>NPOs as an innovative, high-permittivity filler for triboelectric applications. By synergistically integrating the elevated dielectric constant of SrO<inf>2</inf>NPOs with the interfacial polarization of GO NPOs, our optimized composite achieves an outstanding output of approximately 136 V and 2.3 μA/cm<sup>2</sup>under a 100 N force, exceeding the performance of numerous advanced TENGs. Significantly, we convert a common degradation mechanism, i.e., surface protonation, into a functional sensing approach. The device leverages reversible protonation–deprotonation dynamics to convert environmental pH into distinct electrical signals, enabling self-powered, real-time pH sensing. The sensor exhibits excellent linearity (R<sup>2</sup>> 0.97) across three distinct operational regions (pH 1–12), demonstrating high sensitivity to acidity changes. The device has demonstrated remarkable durability, completing approximately 11,000 mechanical cycles. Also, the proposed device serves high chemical durability, maintaining stable performance (up to 6000 cycles) after 24 h immersion in neutral and alkaline solutions. Our work establishes a resilient, multifunctional platform that simultaneously harvests energy and senses its chemical surroundings by reframing protonation as a design principle. This breakthrough paves the way for next-generation TENGs for use in environmental monitoring, resilient IoT networks, and adaptive self-powered electronics that can function under conditions where the chemical environment changes.
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    Synergistic Piezo- and Triboelectricity in a Novel Triglycine Sulfate/Bacterial Cellulose/Chitosan Flexible Composite Nanogenerator
    (2025-08-14)
    Ukasi, Sirinya
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    Saichompoo, Kittipan
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    Sae-tang, Chanachot
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    Pakawanit, Phakkhananan
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    Pongampai, Satana
    Organic piezoelectric materials offer sustainable alternatives for mechanical energy harvesting (MEH), yet their potential remains underexplored compared to inorganic counterparts. This study pioneers the use of triglycine sulfate (TGS), a rarely studied organic piezoelectric, within a flexible three-phase composite with bacterial cellulose (BC) and chitosan (CS) for piezoelectric (PENG) and triboelectric (TENG) nanogenerators. Unlike widely researched systems, TGS's unique hybrid organic–inorganic nature is leveraged here for the first time in MEH. Optimized at a 50:50 BC:CS ratio with 40 wt.% TGS, achieves a TENG output of 141.2 V and 93.3 µA post-poling—1.8 and 2.4 fold higher than unpoled samples—driven by TGS's dipole alignment. Separately, the configuration utilizing a 5 wt.% TGS loading yields 13.7 V and 0.19 µA. Advanced characterization (ATR-FTIR, SR-XTM) and simulations (COMSOL, DFT) reveal TGS's synergy with BC/CS roughness, enhancing charge generation. Delivering 118.65 µW cm<sup>−</sup><sup>2</sup>, the TENG (from the 40 wt.% TGS poled sample) powers a digital watch, showcasing practical promise. This work not only introduces TGS as a novel MEH candidate but also provides mechanistic insights into its polarization, advancing bio-hybrid nanogenerator design.
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    Synergistic Integration of MgAl-LDH Nanosheets into Bacterial Cellulose for High-Performance Triboelectric Nanogenerators
    (2025-08-04)
    Mohsom, Phitchayaphorn
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    Suktep, Natdanai
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    Sae-Tang, Chanachot
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    Pongampai, Satana
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    Pakawanit, Phakkhananan
    A novel nanocomposite design is presented in which magnesium aluminum layered double hydroxide (MgAl-LDH) nanosheets are synergistically integrated with bacterial cellulose (BC) to fabricate a flexible triboelectric nanogenerator (TENG). Utilizing a facile solution synthesis combined with a casting process, composite films with controlled MgAl-LDH loadings (0.25–5% v/v) were developed. The optimal composite, containing 1.5% v/v MgAl-LDH, exhibits an open-circuit voltage (V<inf>OC</inf>) of 88.5 V, a short-circuit current (I<inf>SC</inf>) of 87.7 μA, and a maximum output power (P<inf>max</inf>) of 1250 μW (power density ≈138 μW/cm<sup>2</sup>), which is > 35 times higher than that of pristine BC. Notably, this performance corresponds to a superior filler efficiency metric, demonstrating a highly effective use of the nanosheet additive compared to other reported systems. This performance enhancement is attributed to the multifunctional role of MgAl-LDH nanosheets in increasing the dielectric constant through improved interfacial conductivity and the formation of parallel microcapacitors under an induced electric field. Finite element simulations corroborate the proposed mechanism, and practical demonstrations show the nanocomposite powering 200 LEDs as well as functioning as a self-powered sensor for finger movement monitoring. These findings advance the development of high-performance, flexible energy-harvesting devices.
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    Hybrid Textile Nanogenerators Based on Cotton-PANI/CNT Composites for Simultaneous Harvesting of Mechanical and Thermal Energy
    (2025-06-09)
    Navatragulpisit, Suchanat
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    Saetang, Chanachot
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    Mohsom, Phitchayaphorn
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    Sriphan, Saichon
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    Pakawanit, Phakkhananan
    Rapid advancements in wearable electronics (WEs) have accelerated the development of textile-based triboelectric nanogenerators (T-TENGs) as flexible and sustainable power sources. However, one major challenge lies in mitigating the charge loss due to heat generation during repeated mechanical operations. In this work, we demonstrate a hybrid energy-harvesting textile that integrates both triboelectric and thermoelectric functionalities. Cotton (cot-) fabric serves as the triboelectric substrate, coated with a polyaniline/carbon nanotube (PANI/CNT) thermoelectric composite, enabling the simultaneous harvesting of mechanical and thermal energy. The optimized cot-PANI/CNT device exhibits a high Seebeck coefficient (98.5 mV/K), a power factor of ∼9 μW/mK<sup>2</sup>, and improved electrical conductivity, while maintaining fabric flexibility. The hybrid system achieves an open-circuit voltage (V<inf>OC</inf>) of ∼40.0 V and a short-circuit current (I<inf>SC</inf>) of ∼77.3 μA, yielding a maximum output power of ∼272.3 μW (30.3 μW/cm<sup>2</sup>). The device successfully powers wearable-scale electronics, and mechanistic insights are provided into the synergistic charge generation pathways between the triboelectric and thermoelectric components.
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    Acidic dynamics: Unveiling mechanistic insights for improved performance in chitosan triboelectric nanogenerators
    (2024-07-01)
    Charoonsuk, Thitirat
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    Ukasi, Sirinya
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    Mokthaisong, Panadta
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    Khuntakaew, Pawita
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    Hajra, Sugato
    In recent years, there has been a surge in interest surrounding the development of chitosan (CS)-based triboelectric nanogenerators (TENG) for powering attachable/portable devices. Despite numerous strategies aimed at enhancing their efficiency, the selection of acid solvent has remained largely unexplored. In this study, various acids, including acetic (CH<inf>3</inf>COOH), succinic (C<inf>4</inf>H<inf>6</inf>O<inf>4</inf>), and citric (C<inf>6</inf>H<inf>8</inf>O<inf>7</inf>) acids, were investigated for their impact on mechanical and electrical output signals. Remarkably, the choice and concentration of acid were found to significantly influence performance. Specifically, employing citric acid rendered the CS solid film more pliable and yielded the highest output signal at optimal concentration levels. Under optimized conditions, the CS-TENG exhibited an open-circuit voltage output (V<inf>OC</inf>) of 157 V and short-circuit current output (I<inf>SC</inf>) of 53 µA—more than triple that of pristine CS-TENG. Mechanistic insights into electrical generation have been elucidated, underscoring the importance of solvent selection in CS TENG fabrication. These findings underscore the potential for tailored acid solvent selection to advance specialized applications in the field.
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    Simple Fabrication of Porous 3D Substrate Polydimethylsiloxane (PDMS) Composited with Polyvinylidene Fluoride-co-Hexafluoropropylene (PVDF-HFP) for Triboelectric Nanogenerator
    (2022-01-01)
    Pakawanit, Phakkhananan
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    Pharino, Utchawadee
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    Charoonsuk, Thitirat
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    Sriphan, Saichon
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    Pongampai, Satana
    Owing to their structural advantages over bulk polymers, porous 3D substrates possess immense potential in triboelectric energy generation. This work reports the effective effort to fabricate the porous structure of polydimethylsiloxane, also known as the sponge-PDMS, by a simple template method. The sodium chloride salt from commodity product is used to create the 300 μm size of pores within the PDMS elastomeric layers, turning affects to the mechanical deformability of the triboelectric nanogenerator (TENG). The inner face of those pores is composited with the PVDF-HFP particles as a piezoelectric fillers. The presence of those fillers can be confirmed and their distribution within porous PDMS is 3D visualized by the synchrotron radiation X-ray tomography. The spatial distribution of the PVDF-HFP made it possible to fabricate the piezo-embedded macroporous TENG with high output power of 7.84 μW, giving over 2-fold enhancement, compared with the sponge-PDMS and even more when compared with the flat PDMS film under the same mechanical force.
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    Water Repellent Modified Polyester Fabric Based Triboelectric Nanogenerator for Harvesting Human Mechanical Energies
    (2021-01-01)
    Pharino, Utchawadee
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    Ausaman, Kanyamon
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    Phonimdang, Kunyapak
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    Pongampai, Satana
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    Vittayakorn, Wanwilai
    Wearable triboelectric nanogenerators (TENGs) for converting human mechanical energies into electricity are being investigated widely, because of their potentially diverse applications that come from wearable power supplied to multifunctional self-powered sensing. However, external influences, such as water or high humidity, seriously degrade the electrical output of TENGs. Therefore, a simple method was implemented for fabricating a water repellent fabric-based TENG for harvesting human mechanical energies. Polytetrafluoroethylene (PTFE) or SiO<inf>2</inf> modified by trichloro(octadecyl)silane (OTS) were sprayed onto a polyester (PET) fabric surface to increase hydrophobicity. The PTFE and SiO<inf>2</inf>/OTS coated polyester fabrics exhibited excellent water repellency with a high-water contact angle of ∼144° and ∼153°, respectively. The surface morphology of the coated fabrics showed roughness with a granular structure, which was responsible for air entrapment that prevented water from penetrating the fabric. Furthermore, electrical output of conventional PET fabric-based TENG was found to improve with the deposition of PTFE particles on the fabric surface. By pairing the PTFE coated fabric with aluminum (Al) tape, in order to fabricate TENG, the device generated a maximum voltage of 10.2 V and short-circuit current of 0.20 µA, with a power output of 0.23 (Formula presented.) W/cm<sup>2</sup>, which is 14 times greater than that of SiO<inf>2</inf>/OTS coated fabric-based TENG. The process for achieving water repellent fabric is simple, and the coating materials are available. Thus, a water repellent fabric-based TENG is promising for large-scale production of wearable harvesters from power supplied to multifunctional self-powered sensing.