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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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Simple enhanced charge density of chitosan film by the embedded ion method for the flexible triboelectric nanogenerator
(2022-12-01)
Charoonsuk, Thitirat
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Supansomboon, Supitcha
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Pakawanit, Phakkhananan
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Vittayakorn, Wanwilai
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Pongampai, Satana
This research proposed a simple ionic embedded method to improve electrical output performance by adding surface charges of cationic chitosan (CS) biopolymer for compatible utilization of the triboelectric nanogenerator (TENG). By simply embedding cationic salts, the TENG performance was enhanced by over four times more than that with pristine CS. Moreover, by modifying roughness on the film surface, the optimized condition of R-CS/3 %CaCl<inf>2</inf> reached the highest V<inf>OC</inf> and I<inf>SC</inf> of ~149 V and ~15 μA, respectively, thus exceeding the output from pristine R-CS TENG by four- and three times of ⁓38 V and ⁓5.1 μA. The maximum power output of 400 μW/cm2 can be observed at the 10 MΩ external load resistance. Finally, by integrating an automatic self-charge pumping (ASCP) module, the ASCP/CS-TENG provided highly efficient V<inf>OC</inf> and I<inf>SC</inf> output power by over 1.3 times more than the R-CS/3 %CaCl<inf>2</inf> TENG and could light up 72 light emitting diodes (LEDs) easily.
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Triboelectric-piezoelectric hybrid nanogenerator based on BaTiO3-Nanorods/Chitosan enhanced output performance with self-charge-pumping system
(2021-03-01)
Pongampai, Satana
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Charoonsuk, Thitirat
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Pinpru, Nattapong
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Pulphol, Phieraya
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Vittayakorn, Wanwilai
Recent advances in achieving flexible triboelectric nanogenerators (TENGs) focus widely on utilizing and modifying abundant natural biopolymer. Boosting power generation and conversion efficiency continue to prevail. In this work, three main strategies were proposed to enhance the output performance of chitosan-based TENGs; 1) hybridization with lead-free piezoelectric nanorod, 2) introduction of a soft electrode using bacterial cellulose/carbon nanotube composite to enhance contact efficiency, and 3) enhancement of charge density of the triboelectric friction layer using a self-charge pumping (SCP) module. Under the same testing conditions of 48 ± 5% relative humidity, ~0.55 Hz of frequency, ~250 N of compressive force at 25.0 ± 0.5 °C, and the combination of 7 wt% lead-free piezoelectric BaTiO<inf>3</inf> nanorods (BT-NRs) in the chitosan matrix, the highest open-circuit voltage (V<inf>oc</inf>) of ~111.4 V, short circuit (I<inf>sc</inf>) of ~21.6 μA/cm2, and also output power density of 756 μW/cm2 was achieved. By using an integrated SCP module, the TENGs can provide a V<inf>oc</inf>, I<inf>sc</inf> and peak power output of 247.2 V, 36.7 μA/cm2 and 1568 μW/cm2, respectively. This electrical power output rises to over 4-fold more power enhancement than that of pristine chitosan TENGs. The TENGs demonstrate remarkable mechanical stability and reliability upon cyclical contact for up to 3000 times. This work provides a promising strategy for achieving high-output, eco-friendly triboelectric nanogenerators. By boosting the output performance via continuous charge pumping, ultrahigh effective charge density was achieved successfully in flexible chitosan/BT-NR biocomposites that can push output performance towards real applications of TENGs.
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Effect of different crosslinking agents on properties of dual modified starch biodegradable films prepared by crosslinked-oxidized method
(2020-01-01)
Tanetrungroj, Yossathorn
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Prachayawarakorn, Jutarat
Dual modified starch films were prepared by using crosslinked-oxidized starch via hydrogen peroxide and different crosslinking agents, including borax and a mixture of sodium trimetaphosphate/ sodium tripolyphosphate. The effect of different crosslinking agents on the properties of dual modified films was examined and compared to single modified starch films. The crosslinked and oxidation reactions were confirmed by diminished intensity peaks of hydrogen bonding and new IR peaks of carbonyl and carboxyl groups. Tensile strength and hydrophobicity of native starch film, and elongation of crosslinked starch films were improved by crosslinked-oxidized method, especially for crosslinked starch film with borax.
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Characterization and properties of biodegradable thermoplastic grafted starch films by different contents of methacrylic acid
(2019-02-15)
Weerapoprasit, Chayapa
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Prachayawarakorn, Jutarat
Due to poor mechanical and thermal properties of native starch (NS) film; in the present work; NS was modified by graft copolymerization. Thermoplastic starch (TPS) grafted by methacrylic acid (MAA) with different percentage of grafting, i.e., 0%, 18.3%, 36.3%, 52.1% and 89.7% were prepared and tested. The result demonstrated that the intensity of IR peak of acrylic group increased with the increasing percentage of grafting. The higher graft copolymerization with MAA also significantly reduced degree of crystallinity. The strain at maximum load of TPS film grafted by MAA increased with the increasing percentage of grafting. However, water uptake of TPS film grafted by MAA reduced with high percentage of grafting (52.1% and 89.7%). In addition, different TPS films grafted by MAA were also examined for morphology, water vapor permeability, thermal property and biodegradable property by soil buried test.
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A Real-time rheological measurement for biopolymer 3D printing process
(2018-01-01)
Yokpradit, Anchyza
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Tongloy, Teerawat
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Kaewpirom, Supranee
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Boonsang, Siridech
Biopolymers combined with 3D printing technology for tissue engineering have been extensively used in many biomedical applications such as organ and tissue regeneration. The 3D printing technology generally relies on a continuous dispensing process, which is usually known as complicated dynamic processes. This is primarily caused by the rheological properties of materials. In addition, the primary concern for biopolymer printing is the timedependent variation of material properties such as viscosity during the printing process. The variation of rheological properties significantly affects the printing process especially the volume flow rate control. In general, the measurement of rheological properties is carried out before the dispensing process. The setting up of fluid flow control is usually performed according to parameters derived from the premeasured rheological values. However, such a method may not provide optimized parameters for printing control with some biopolymers. An innovative method of measuring rheological properties is proposed in this paper. An image processing procedure is employed to determine the fluid flow at a certain time in the fluid dispensing process. Experiments were carried out in which the rheological properties of poly- (vinyl alcohol) (PVA) and poly-(vinyl alcohol)/chitosan (PVA/CS) aqueous solutions used for dispensing the polymers were evaluated at different time stamps and applied pressures. The measured flow rates were used to construct a pressure-dependent fluid flow rate curve as a function of time to identify the rheological properties of fluid materials under specific times and conditions.
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Development of hydroxyethylacryl chitosan/alginate hydrogel films for biomedical application
(2014-12-01)
Treenate, Pitchaya
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Monvisade, Pathavuth
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Yamaguchi, Masayuki
Novel hydrogel films composed of hydroxyethylacryl chitosan (HC) and sodium alginate (SA) were prepared for biomedical application by using calcium chloride (CaCl<inf>2</inf>) as a nontoxic ionic crosslinker to form a semi-interpenetrating polymer network (semi-IPN). HC was successfully prepared by following a Michael addition reaction of chitosan (CS) and hydroxyethylacrylate completely dissolved in distilled water at 70 °C. The distribution pattern of Ca2+ ions were well-dispersed within the hydrogel films examined by scanning electron microscope-energy dispersive spectrometry (SEM-EDS), implying uniformity of crosslinking. The swelling behavior of the hydrogel films in distilled water, simulated gastric fluid (SGF, pH = 1.2) and phosphate buffer solution (PBS, pH = 7.4) were investigated. The equilibrium swelling degree of the hydrogel films in distilled water increased with a decreas of either the SA content or the concentration of CaCl<inf>2</inf>. The hydrogel films showed pH-dependent behavior in that the shapes of the hydrogel films were stable in SGF while they degraded in PBS. The tensile strength and elongation of the hydrogel films reached 12.1 MPa and 162%, respectively, which presented reasonable mechanical properties during use and enough flexibility to follow skin movement. Cell viability of the hydrogels was measured using a methylthiazol tetrazolium (MTT) assay. The results indicated that the hydrogel films are not cytotoxic.

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