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Upcycling waste mycelium into chitosan-based biodegradable triboelectric nanogenerators with enhanced energy output
(2026-12-01)
Panpho, Phakakorn
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Charoonsuk, Thitirat
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Pakawanit, Phakkhananan
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Bongkarn, Theerachai
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Vitayakorn, Narathip
Sustainable nanogenerators require bio-based active layers that combine interfacial polarization, mechanical deformability, and stable charge generation. Herein, waste mushroom mycelium (WMM) was upcycled as a multifunctional biofiller in chitosan (CTS)-based films for piezoelectric/triboelectric energy-harvesting devices. By controlling WMM loading and glycerol plasticization, this study reveals a morphology–dielectric–compliance coupling mechanism governing device performance. FTIR, XRD, SEM, and X-ray tomographic analyses show that WMM modifies hydrogen bonding, chain packing, surface texture, and internal filler connectivity, while excessive loading causes aggregation and structural non-uniformity. The optimized 7 wt% WMM/CTS film produced a PENG-mode output of 1.87 V and 1.72 μA and a TENG output of 15.39 V and 2.54 μA. The output of the TENG was further improved to 20.35 V and 2.80 μA at a maximum power of about 44 μW with glycerol plasticization. Capacitor charging, cyclic operation, LED array illumination and seven-segment display were also shown with the optimized device. Notably, the highest low-frequency apparent permittivity was observed at 11 wt% WMM/CTS, but its output decreased because of aggregation, dielectric loss, and mechanical non-uniformity. These results demonstrate that optimum energy harvesting is governed not by dielectric permittivity alone but by balanced polar interfaces, surface asperity, moderate dielectric loss, and contact compliance. This work establishes waste mycelium as a functional biofiller for sustainable biopolymer active layers in low-power self-powered systems.
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Integration of CCTAO/PDMS composite films into proximity capacitive sensor devices
(2026-12-01)
Bongkarn, Theerachai
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Panpho, Phakakorn
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Charoonsuk, Thitirat
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Vittayakorn, Naratip
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Pakawanit, Phakkhananan
Flexible capacitive proximity sensors are promising for contactless sensing applications, but their performance is strongly influenced by the dielectric properties and microstructure of the sensing layer. In this work, CaCu<inf>3</inf>Ti<inf>4-x</inf>A<inf>x</inf>O<inf>12</inf>/polydimethylsiloxane (CCTAO/PDMS, A = Nd3+ or Gd3+) composite films were developed as flexible dielectric layers for interdigitated capacitive proximity sensors. Nd- and Gd-doped CCTO ceramics were synthesized by a solid-state reaction method and incorporated into a PDMS matrix at different filler loadings. Structural analysis confirmed that the CCTAO ceramics retained the cubic CCTO phase after rare-earth substitution, while the composite films preserved the characteristic amorphous structure of PDMS with embedded ceramic fillers. The FESEM, EDS mapping and X-ray tomographic microscopy analyses showed that the CCTNdO/PDMS composite had a more uniform distribution of ceramic particles than the CCTO/PDMS system. The dielectric measurements demonstrated the improvement in the dielectric constant of the PDMS-based composites upon CCTNdO incorporation and also indicated that the composites did not exhibit any significant changes in their dielectric properties across the range of frequencies examined. The CCTNdO/PDMS films were found to show the negative capacitance response as a function of distance due to the electric-field shunting mechanism when used in an interdigitated capacitor sensor. The sensor with composition 10 wt% CCTNdO/PDMS had excellent performance with a maximum normalized capacitance change equal to −8.70%, which corresponds to a proximity sensitivity of around 0.42%/mm and an effective sensing range of around 20 mm. It is concluded that the optimization of the loading of the rare-earth material in a flexible PDMS matrix is an effective approach to achieve a compromise between the dielectric enhancement of the sensor and the dispersion of the filler and fringing-field interaction in the contactless capacitive proximity sensor.
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The Y3+ Donor-Doped CCTO (Ca0.95Y0.05Cu3Ti4O12) Dielectric Fillers for Electrical Output Enhancement of Flexible Triboelectric Nanogenerator
(2026-06-03)
Saichompoo, Kittipan
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Rattanawongwiboon, Thitirat
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Kingkam, Wilasinee
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Pakawanit, Phakkhananan
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Sukkha, Usa
The escalating wearable electronic devices with their flexible energy sources demand has rendered the imperative scientific challenge on the development of materials for the flexible triboelectric nanogenerators (F-TENG), one of advanced energy harvesting systems. Dielectric material optimization, the Y3+ donor-doped calcium copper titanate based on exactly stoichiometric Ca<inf>0.95</inf>Y<inf>0.05</inf>Cu<inf>3</inf>Ti<inf>4</inf>O<inf>12</inf> (CCTYO), serves as a critical pathway in this work for achieving enhanced F-TENG via compositing with the polydimethylsiloxane (PDMS) polymer. The enhancement of electrical output has garnered substantial interest owing to its increased relative permittivity ((Formula presented.)). The influence of the loaded CCTYO amounts on structure, morphologies, dielectric properties, and electrical output, including open-circuit voltage (V<inf>OC</inf>), short-circuit current (I<inf>SC</inf>) and power density for PDMS/CCTYO composites is investigated. As compared with loading undoped CCTO, the additional Y3+ can improve higher F-TENG output by increasing the (Formula presented.) along with maintaining the loss tangent (tan δ < 0.02) at optimized condition. The appropriate amounts of CCTYO 0.75 wt% make the PDMS/CCTYO F-TENG to achieve V<inf>OC</inf> of ∼76.4 V (8.5 V/cm2) and I<inf>SC</inf> of ∼130.0 μA (14.4 μA/cm2), which were higher than pristine PDMS for 2.7 and 4.3 times. The power density of 53 µW/cm2 is 8.9 times higher than that of 6.3 µW/cm2 from the pristine PDMS. This study also provides a COMSOL multiphysics simulation, bridging laboratory experiments, for quantifying the triboelectric capability of dielectric materials.
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Cold sintering-assisted low temperature fabrication of dense Ba5Nb4O15 ceramics
(2026-06-08)
Sukkha, Usa
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Teandam, Apichayaporn
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Pakawanit, Phakkhananan
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Kamonpha, Phitsamai
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Vittayakorn, Wanwilai
This study presents a novel approach for fabricating Ba<inf>5</inf>Nb<inf>4</inf>O<inf>15</inf> (BNO) ceramics at low sintering temperatures via the cold sintering process (CSP), using Ba(OH)<inf>2</inf>·8H<inf>2</inf>O (BOH) as a transient liquid phase. CSP was performed under an external pressure of 10MPa with a sintering temperature range of 150°C to 300°C. Optimally, BNO-BOH ceramics achieved a relative density of 93.7 ± 0.43 when sintered at 250°C for 1h. Scanning electron microscopy (SEM) suggested that particle densification occurred via a dissolution-precipitation process, which filled pores and formed necks between particles. The study demonstrates that the residual liquid content is crucial for ceramic densification. Annealing the as-cold sintered BNO-BOH ceramics at 1000°C for 1h successfully eliminates the BaCO<inf>3</inf> secondary phase. Furthermore, dielectric properties of annealed ceramics were also characterized at room temperature from frequency range of 20Hz to 2MHz. The dielectric permittivity is reported to be 39.2 and 0.01 for tanδ at 1.8MHz. The cold sintering process provides an effective strategy to reduce the sintering temperature while achieving high relative density. This method offers a promising alternative for the fabrication of advanced ceramics.
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An architected silk fibroin-lignin multilayer with deep-level trapping states for high-output triboelectric nanogenerators
(2026-03-01)
Suktep, Natdanai
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Sae-tang, Chanachot
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Ukasi, Sirinya
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Pakawanit, Phakkhananan
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Supansomboon, Supitcha
Biopolymer-based triboelectric nanogenerators (B-TENGs) are promising power sources for sustainable and flexible electronics, but their performance is often limited by severe charge recombination at the triboelectric interface. To overcome this critical bottleneck, we report an architected multilayer B-TENG featuring a silk fibroin (SF)/MgAl LDH composite as the charge-generating layer and, to our knowledge, for the first time, a lignin-functionalized SF film as a dedicated charge-trapping layer. The strategic incorporation of lignin, an abundant and sustainable biopolymer, introduces deep-level electronic trapping states originating from its abundant aromatic moieties. That effectively suppresses interfacial charge recombination and prolongs charge lifetime. By optimizing the contents of MgAl LDH and lignin, the device achieves a measured open circuit output voltage ( V <inf> OC </inf>) and current density ( J <inf> SC </inf>) of 96 V and 6.56 μA/cm3, with a maximum output power ( P <inf> max </inf>) of 205 μW, corresponding to a power density of 22.7 μW/cm2. We also propose a mechanistic linking of deep-level traps to prolonged charge lifetime and increased net transferable charge. The interface-engineering strategy demonstrated here paves the way for developing high-performance and sustainable biopolymer-based TENGs and motion sensors.
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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/cm2under 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 (R2> 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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Titanate Nanosheets/Cellulose Composite Showing Improved Crystallinity and Decreased Water Wettability by Gamma-Irradiation
(2025-11-25)
Tariwong, Yaowaluk
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Pulphol, Phieraya
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Sangtawesin, Tanagorn
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Seriwattanachai, Chaowaphat
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Kanjanaboos, Pongsakorn
While molecularly thin nanosheets have been increasingly studied as functional coatings, their use as a hydrophobic and γ-irradiation-tolerant component in biologically derived matrices is to be demonstrated. Herein, simple dip-coating was employed to fabricate titanate nanosheets/cellulose composites, which were subjected to γ-irradiation up to 50 kGy. Their surface chemistry was evaluated by water contact angle (WCA) measurements and X-ray photoelectron spectroscopy (XPS). Upon irradiation, the WCA of all samples nonmonotonically increased in three stages from ∼29 to 50° (noncoated) and ∼46 to 80° (composite, optimized at ∼1.2 wt %Ti loading, or 0.2 mg·cm–2). The titanium content and the 4+ valence did not change with the dose, suggesting the radiolytic stability. The dual surface modification occurs while cellulose fiber morphology and nanoscale mechanical properties are preserved. The increased WCA at the cellulose-part is explained by the γ-irradiation-induced crystallization according to the increased crystallinity index and improved thermal stability. At the other component, nanosheet coating results in increased surface roughness and diminished water–surface interactions. The latter is deduced from DSC measurements of water evaporation from pristine and 50 kGy-irradiated Cs<inf>0.7</inf>Ti<inf>1.825</inf>O<inf>4</inf>layered crystal-a nanosheet precursor. Our work suggests further exploration of nanosheets with diverse structures and compositions as coatings or fillers, which could find applications in γ-irradiation-sterilized barrier films.
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A Kirigami-Engineered “Skeletal Framework” Composite for Ultralow Hysteresis and Highly Stable Strain Sensors
(2025-11-24)
Pongampai, Satana
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Chaithaweep, Kanokwan
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Pakawanit, Phakkhananan
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Charoonsuk, Thitirat
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Bongkarn, Theerachai
Wearable strain sensors are pivotal for next-generation human–machine interfaces, yet achieving high fidelity, robustness, and sustainability in a single platform remains a significant challenge. A primary obstacle is the inherent viscoelasticity of soft materials, which leads to signal drift and hysteresis. Here, we report a highly stretchable and ultrastable strain sensor fabricated through a synergistic integration of Kirigami-based structural engineering and nanocomposite material design. By introducing titanium dioxide nanotubes (TNTs) into a bacterial cellulose (BC) matrix, we create a composite with a unique internal “skeletal framework”. This framework substantially reduces viscoelastic losses, resulting in an exceptionally low hysteresis of 0.6% and ensuring robust performance with 99.4% signal stability over >10 000 cycles. Concurrently, the Kirigami-patterned structure enhances stretchability to ∼235% while the framework amplifies sensitivity 5.8-fold. The practical viability of this high-fidelity sensor is demonstrated through the precise and repeatable control of a robotic arm, where ultralow hysteresis proves more critical than raw sensitivity. The sensor’s eco-friendly, water-based fabrication aligns high-fidelity sensing with sustainable processing, presenting a clear design paradigm for engineering reliable and eco-conscious wearable electronic devices.
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The Study of Lightweight Expanded Clay Aggregate from Industrial Waste
(2025-09-01)
Kaewsit, Sriwan
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Sompong, Khanisorn
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Pakawanit, Phakkhananan
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Akkalatham, Wareerath
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Yongsiri, Ploypailin
This study aims to investigate the utilization of lightweight expanded clay aggregate (LECA) produced by combining clay with industrial waste as a planting material for soil moisture retention. Lightweight expanded clay aggregate is a growing media material composed of clay pellets subjected to high temperatures. This substance is created by combining clay with pore-forming elements, such as pulverized waste from the automotive sector. The compressed waste particles comprise polymer fiber, glass shards, lubricating oil, and various other components. This waste is imported from overseas to serve as a cost-effective fuel source for energy production. In order to further develop its potential applications, it is combined with clay to investigate the feasibility of developing a novel substrate to replace materials like perlite and vermiculite that are currently in use. The experiment entails molding a mixture of clay and waste fragments in different proportions and subjecting them to fire at temperatures ranging from 700 to 800 degrees Celsius. The research results indicated that 30% of clay with 70% of industrial waste is the most suitable combination and slip casting parameters. Examining the physical and chemical characteristics of the LECA reveals that they possess pores capable of efficiently retaining water and moisture. The bulk density was 1.05 g/cm³, the apparent porosity was 53.21%, and the water absorption was 50.60%, which indicates their high capacity to absorb water. The pH of LECA suited for plant growth commonly lies within the range of 6.5 to 8, which is close to the suitable pH value. The experiment has yielded a novel, highly permeable, lightweight expanded clay aggregate that efficiently retains moisture in the topsoil and is available in many forms. Furthermore, using industrial waste and employing low-forming temperatures enable this innovation to be ecologically sustainable.
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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/cm2), 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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