【公開日：2023.08.01】【最終更新日：2023.05.08】

課題データ / Project Data

課題番号 / Project Issue Number

22KT0041

利用課題名 / Title

Advanced transmission electron microscopy investigation of energy storage nanomaterials  [藤ヶ谷1]Write the name of the subject that can understand the research purpose, usage, etc. Usage subject names don't have to be the same as research theme names. Be sure to describe  the usage properly.

利用した実施機関 / Support Institute

京都大学 / Kyoto Univ.

機関外・機関内の利用 / External or Internal Use

外部利用/External Use

技術領域 / Technology Area

【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-

【重要技術領域 / Important Technology Area】（主 / Main）革新的なエネルギー変換を可能とするマテリアル/Materials enabling innovative energy conversion（副 / Sub）次世代ナノスケールマテリアル/Next-generation nanoscale materials

キーワード / Keywords

電子顕微鏡/Electron microscopy,電極材料/ Electrode material,エネルギー貯蔵/ Energy storage,ナノ粒子/ Nanoparticles,Chemical synthesis, Biomass recycling, Catalytic graphitization, In-situ polymerization, Heat treatment, Iron Oxide, Carbon, Silica, Silicon, Graphene, Conducting polymer, Self-healing materials, Nanoparticles, Nanocomposites, Quantum dots, Anode materials, Energy storage materials, Lithium-ion batteries, Sustainable energy, alternative energy, Advanced electron microscopy, Transmission electron microscopy, Nanostructural study, Electron energy loss spectroscopy, High-resolution transmission electron microscopy, Scanning transmission electron microscopy

利用者と利用形態 / User and Support Type

利用者名（課題申請者）/ User Name (Project Applicant)

Sarakonsri Thapanee

所属名 / Affiliation

Department of Chemistry, Faculty of Science, Chiang Mai University

共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes

Thanapat Autthawong,Natthakan Ratsameetammajak,Waewwow Yodying,Yothin Chimupala

ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes

清村　勤,山口　睦

利用形態 / Support Type

（主 / Main）技術代行/Technology Substitution（副 / Sub）-

利用した主な設備 / Equipment Used in This Project

KT-403：モノクロメータ搭載低加速原子分解能分析電子顕微鏡

報告書データ / Report

概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)

All samples, including C/FeO_x, PPy/SiO₂@rGO, SA-PPy@Nano-SiO₂/C, SA-PPy@SiQDs/C, SnS/C, and SnO₂/C, were synthesized, characterized, and electrochemically measured at Chiang Mai University, Chiang Mai, Thailand. Then, the advanced electron microscope study was performed at Kyoto University, Kyoto, Japan.
For the C/FeO_x nanocomposite derived from water hyacinth, its morphology was visualized by TEM to have various types of nanoparticles uniformly distributed on the matrix. TEM images and corresponding SAED patterns of each type of nanoparticle were taken and indexed. It was found that the rod-shaped nanoparticles are chlorapatite (Ca species), and the round nanoparticles are Fe₃O₄. Both carbon sheets and nanoparticles were further identified by HAADF-STEM and EDS mapping. The HAADF-STEM image displays the contrast between the matrix and nanoparticles and clearly visualizes the distribution behavior within the nanocomposite. Furthermore, EDS mapping insisted that the matrix of C/FeO_x consists of carbon, while each type of nanoparticle contains representative elements of FeO_x, K, and Ca species that corresponded to SAED patterns. The carbon component in the nanocomposite was further confirmed by HR-TEM and EELS to be small graphitic carbon domains scattered within an amorphous carbon matrix, which was also in correspondence with Raman spectroscopy.
For the Polypyrrole (PPy)-coated Silica@reduced graphene oxide, SEM images of PPy/SiO₂@rGO have already proven a wrapping morphology. The TEM results indicate that the SiO₂ nanoparticles are well dispersed on the RGO sheet. Furthermore, the SEM and TEM images clarify the PPy coating layer on the surface of the SiO₂@rGO nanocomposite. The uniform distribution of C, N, O, and Si elements confirms a homogeneous mixture of rGO and SiO₂ and a uniform distribution of PPy on the surface of SiO₂@rGO nanocomposite particles. The incorporation of PPy/SiO₂@rGO nanocomposites resulted in the conformal conductive coating surrounding SiO2@rGO nanoparticles, (i) buffering the tension produced by volume expansion, (ii) providing a good electrical connection to the particles, and (iii) promoting the formation of a stable SEI layer on the electrode surface, enhancing the cycling properties. The modified SiO₂/rGO exhibited high reversible specific capacity, good rate properties, and extremely excellent cycling stability. For the pre-cycled and post-cycled SA-PPy@Nano-SiO₂/C electrode materials, the PPy contains nano-SiO₂/C, and their presence within the nanocomposite was also evidenced by TEM analysis. The SiO₂ nanoparticles are covered by both carbon and PPy, which strongly affects the contrast of the HAADF-STEM image. The high-resolution TEM image shows the distribution and crystalline size of SiQDs, while the STEM-EDS mapping profile confirms that the constitutive silicon and nitrogen elements are the SiO₂ nanoparticles and PPy network, respectively. Moreover, the synthesized nano-silica, with an average size of 5.17 nm, was obtained together with a carbon sheet and also covered by a conductive polymer network and cluster of PPy. After a long-term cycle, the silica nanoparticles transformed into Si quantum dots (2.40 nm). Interestingly, the thin, stable SEI layer was formed and covered this material; also, all SiQDs were embedded within the PPy network. These formations, as well as the self-healing character of the SA-PPy network, could be served by the double protection of this electrode, promoting superior cycling stability, and preventing the electrode from cracking after many charge-discharge cycles. For the new composited materials used as the anode in lithium-ion batteries, SnO₂/C and SnS₂/C derived from popped rice as carbon precursors were synthesized and characterized. The pop-rice carbon was used as a supporter for loading SnO₂ and SnS₂ nanoparticles via the coprecipitation method. Advanced transmission electron microscope techniques such as high-resolution EDS mapping and high-resolution TEM images revealed the good distribution of the quantum dots SnO₂ and hexagonal nanoplates SnS₂ in the carbon matrix. The preliminary battery testing results showed that this anode material provided a higher specific capacity and maintained cycle stability better than the commercial anode.

実験 / Experimental

All samples, including C/FeO_x, PPy/SiO₂@rGO, SA-PPy@Nano-SiO₂/C, SA-PPy@SiQDs/C, SnS/C, and SnO₂/C, were synthesized, characterized, and electrochemically measured. Then, the advanced electron microscope study was performed. To investigate the in-depth nanostructure of novel nanocomposite anode materials in lithium-ion batteries, the synthesized nanocomposite materials were investigated by high-resolution energy transmission electron microscopy (TEM-ARM200F). To observe their morphology, shape, and particle size at the nanoscale, transmission images were taken. A scanning transmission electron microscope equipped with EDS mapping was also used to study the elemental distribution and composition of individual particles in the synthesized materials. To identify the distribution through the phase and atomic density difference, dark-field TEM images were performed on all synthesized materials. In the sample of C/FeO_x, the degree of graphitization of this nanocomposite was studied by electron energy loss spectroscopy (EELS) to confirm the Raman spectroscopy result. In the C/FeO_x and SA-PPy@SiQDs/C nanocomposites, the high-resolution TEM images (HR-TEM) were used to reveal the lattice fringes in order to analyze and index the graphitization characteristics of carbon in the C/FeO_x and also the phase transformation of SiQDs during charge-discharge processes.

結果と考察 / Results and Discussion

Project 1: C/FeO_x composite materials derived from water hyacinth stem for use as anode in lithium-ion batteries The C/FeO_x composite materials were prepared using water hyacinth (WH) stem waste as a precursor to use as an anode in lithium-ion batteries. Using iron-assisted catalytic graphitization, both carbon and FeO_x components could be obtained simultaneously from a one-step reaction and eliminate the need for extra catalyst removal steps. In theory, carbon acts as a matrix to relieve the volume change effects of FeO_x, while FeO_x enhances the specific capacity. The structure of carbon and the distribution of components could influence the conductivity and overall performance of the composite. Hence, the morphology and distribution behavior of each component in the synthesized materials need to be thoroughly studied. To begin with, the C/FeO_x material with the best electrochemical performance (WH0.03) was chosen as a representative to observe in transmission electron microscopy (TEM). The overall TEM image of WH0.03 in Figure 1(a) displays the thin carbon sheet with various types of nanoparticles dispersed on the surface. The close-up TEM images of individual nanoparticles along with their corresponding SAED patterns were retrieved to identify the components. As shown in Figures 1(b) and 1(c), the spot patterns obtained could confirm that the round nanoparticles consisted of Fe₃O₄, while the pattern from the rod-shaped nanocrystalline was well matched with chlorapatite (Ca₅(PO₄)₃F_0.09Cl_0.88). Both are the components detected earlier by X-ray analysis. Moreover, EDS mapping was also performed on the WH0.03 sample. In Figure 1(d), the main elements selected for each component consisted of C for the carbon matrix, Fe for FeO_x, Moreover, O, Ca, K, and Cl were used to display distributions of Ca and K species. The EDS mapping provided strong evidence that the straightforward catalytic graphitization could produce C/FeO_x materials with each component dispersed evenly on the carbon support.

Project 2: Electrochemical enhancement of Rice husk derived-Silica/Reduced Graphene Oxide wrapped conductive Polypyrrole as nanocomposite Anode Materials for Lithium-ion Batteries Polypyrrole (PPy) coated Silica@reduced graphene oxide nanocomposite (PPy/SiO₂@rGO) as an anode material has been developed by a simple composite technique followed by an in-situ polymerization process for lithium-ion batteries. The architecture of reduced graphene oxide offers a larger electrode/electrolyte interface to promote the charge-transfer reactions and provide sufficient space to buffer a large volume expansion of SiO₂, maintaining the mechanical integrity of the overall electrode during the lithiation/delithiation process. Moreover, the conducting polymer coating not only improves the electric conductivity of SiO₂, but also suppresses the volume expansion and rapid capacity fading caused by serious pulverization. As depicted in Figure 3, morphological and microstructural analysis of synthesized materials was conducted by acquiring SEM and TEM images. The microstructural characteristics of synthesized polypyrrole (PPy), as displayed in Figure 3(a), revealed irregular granular particles, which is consistent with previous research.^1,2 In-situ oxidative polymerization of the pyrrole monomer resulted in the formation and coating of PPy layers on the surface of RGO-SiO₂. It is essential to note that PPy layers were uniformly distributed on the RGO-SiO₂ surfaces, as evidenced by the SEM and TEM images (Figure 3). This was responsible for the enhanced thermal and electrical properties of the resulting composites. In the case of the nanocomposite, RGO-SiO₂ functions as a template for the formation of RGO-SiO₂@PPy. As the pyrrole monomer was added to the RGO-SiO₂ suspension, it was absorbed on the surface via π – π interactions, the van der Waals force, and hydrogen bonding.^3–5 PPy exhibits irregular granular structures under high magnification (Figure 3(a)), whereas RGO-SiO₂ nanocomposites display a honeycomb-like structure (Figure 3(b)). Figure 3(c) depicts a gauzy and wrinkly structure containing a globular cluster of polypyrrole matrix incorporating RGO sheet and SiO₂ nanoparticles. Figure 3(d) makes it simple to observe the layer thickness for the RGO sheet and the SiO₂ entrapment in the matrix. For the desired composites, RGO-SiO₂@PPy, a wrapping morphology is observed in which exfoliated RGO films serve as templates for SiO₂@PPy. The surface of the RGO sheet is coated with SiO₂@PPy nanoparticles. Figure 3(f) additionally verifies the PPy coating layer on the surface of the RGO-SiO₂ nanocomposite. In addition, PPy@SiO₂ films likely have π – π stacking with RGO films. The TEM element mapping images (Figure 4) reveal an even distribution of C (carbon), N (nitrogen), O (oxygen), and Si (silicon) elements, confirming the homogeneous mixture of RGO and SiO₂ and the uniform distribution of PPy on the surface of the RGO-SiO₂ nanocomposite particles

Project 3: Mechanically Robust Self-Healing Alginate-Polypyrrole@Nano-SiO₂/C Anode Materials Using Waste Recycling of Streblus Asper for Sustainable Li-Polymer Batteries In this work, we have proposed a green nanocomposite design that is simple, cost-effective, and environmentally friendly to prepare PPy@Nano-SiO₂/C nanocomposite materials as anode materials for LIBs in two steps: The self-assembled SiO₂ that uniformly exists within amorphous carbon was first derived from SAL biomass leaves via thermal treatment. The PPy@Nano-SiO₂/C nanocomposites were then produced through in-situ polymerization of pyrrole monomer using iron(III) chloride as an initiator, affording the SiO₂ nanoparticles in these synthesized composites with dual protection and self-healing properties. Herein, we introduce the first report that utilizes Streblus asper leaves as a raw resource for PPy@Nano-SiO₂/C nanocomposite. Also, the proportional effects and electrochemical properties of nanocomposites were examined by comparing the performance differences between the synthesized materials. The derived natural carbon is a great host for active SiO₂ nanoparticles, whereas polypyrrole can act as a stable and conductive network with better electrical conductivity and cycle stability. All the factors listed above make PPy@Nano-SiO₂/C nanocomposites a promising alternative green anode material for cost-effective LIBs. A TEM investigation was performed to determine the morphology and structure of nanocomposite electrodes. Figure 5 displays TEM images of pre-cycled and post-cycled PPy@Nano-SiO₂/C nanocomposite electrodes along with selected area electron diffraction (SAED) analysis and particle diameter histograms of SiO₂ nanoparticles (SiO₂ NPs) and Si nanoparticles (Si NPs) in the carbon matrix and polymeric network. For the pre-cycled PPy@Nano-SiO₂/C electrode, as depicted in Figures 5(a) and 5(b), SiO₂ NPs were principally observed in two configurations: agglomerated particles and dissociated SiO₂ NPs. The particles are highly aggregated together due to their small size and Van der Waal’s forces. However, the size of the cluster is still as large as the nanoscale. Furthermore, it is evident that the spherical SiO₂ NPs developed predominantly within the carbon matrix. Figure 5(c) represents the corresponding particle size distribution of SiO₂ NPs. It is evident that the diameter of the SiO₂ NPs varied from 2 to 10 nm, with an average value of 5.17 nm. According to the SAED pattern (inset of Figure 2(c)), the amorphous structure was revealed. This can be identified as the amorphous nature of SiO₂ and low crystalline carbon. To examine the in-depth structure of carbon, the area of the carbon sheet was specifically taken, as shown in Figure 6. The TEM image (Figure 6(a)) revealed a thin sheet structure, with the SAED pattern corresponding to low crystalline carbon. Thus, in the HRTEM observation, the lattice view of the carbon sheet is shown in Figure 6(b), exposing the pseudo-graphitic nature of disordered hard carbon microstructures incorporating graphitic domains.⁶ For the post-cycled PPy@Nano-SiO₂/C electrode, Figure 5(d) demonstrates that the small particles were evenly distributed and embedded inside the carbon matrix and self-healing polymeric network. The SAED pattern depicted in the inset of Figure 5(d) exhibits three polycrystalline rings consistent with those of the Si (111), LiO₂ (110), and Si (220) planes. These could verify the lithiation-delithiation mechanism that converts SiO₂ NPs to Si quantum dots (Si QDs), whereas the SA-PPy polymer was transformed from spherical agglomerates to 3-dimensional networks. Figure 5(e) depicts the formation of the irreversible LiO₂ reaction at this stage, which corresponds to the formation of the ~3 nm thick SEI layer. A histogram analysis reveals that the Si QDs are monodispersed and have an average size of 2.40 nm. Due to the ultrafine size of Si QDs, the high surface area interacting with Li-ion enables a rapid lithiation and delithiation rate, enhancing specific capacity during long-term battery cycling. The crystallinity of the Si-NPs in the post-cycled electrode was further investigated by high-resolution transmission electron microscopy (HR-TEM image). Figure 3(g) shows the HR-TEM of Si-QDs distributed onto the carbon layer. We can observe the crystalline structure of QDs, which displays the (111) lattice sets with an interplanar spacing of 3.10 Å, characteristic of Si. Figure 5(h) shows the HAADF-STEM image of a single sheet of PPy@Nano-SiO₂/C nanocomposite containing relatively heavy elements uniformly on the plate and lighter elements implied as the Si element of SiO₂ nanoparticles. The result clearly elucidates the PPy@Nano-SiO₂/C nanocomposite structure where the SiO₂ nanoparticles are denser than the carbon layer and conductive polymer network. Figure 5(i-l) shows the results of the STEM-EDS elemental mapping analysis. The individual elemental maps show the relative positions of the synthesized materials, clearly identifying the plate structure visually decorated with carbon and SiO₂, which correspond to the C K edge (i), O K edge (j), and Si K edge (k), respectively. Moreover, this is unambiguous evidence of PPy network structure showing that N K edge (l) signals are localized in a good dispersion on the SiO₂/C nanocomposite area. From these advanced electron microscopy results, this work enriches the electrode engineering technology of nanocomposite materials using biomass waste recycling and opens up a new way to customize the self-healing anode for green and sustainable lithium-ion batteries.

Project 4: SnO₂/C and SnO₂&SnS₂/C nanocomposites The new composite materials used as anodes in lithium-ion batteries, SnO₂/C and SnS₂/C derived from popped rice as carbon precursors, were synthesized and characterized. First, the pop-rice carbon was prepared by KOH treatment and calcination at 800^oC. The pop-rice carbon was used as a supporter for loading SnO₂ and SnS₂ nanoparticles via the coprecipitation method. In theory, pop-rice carbon is not only a supporter but also acts as a matrix to relieve the volume change effects of SnO₂ and SnS₂, while SnO₂ and SnS₂ enhance the specific capacity. The SnO₂/C was first characterized by an advanced transmission electron microscope (TEM). The bright field TEM image and high-resolution TEM images of the SnO₂/C shown in Figure 7 reveal the well-distributed, uniform 3-5 nm quantum dot SnO₂ in the carbon matrix. Moreover, the surface of the samples was intensely coated with quantum dot SnO₂. EDS mapping images also confirmed the location of the SnO₂ quantum dot in the carbon media. The EDS images show the well-dispersed Sn and O elements with the strong X-ray singles in the bulk carbon media. The composite of SnS₂&SnO₂ nanoparticles on carbon derived from popped rice was investigated by an advanced transmission electron microscope (TEM). The dark field TEM images of the samples shown in Figure 8 reveal SnS₂ hexagonal plates with well-distributed SnO₂ particles on the surface of the hexagonal plates in the carbon matrix. The EDS mapping images also show the well-dispersed Sn, S, and O elements with the strong X-ray signals in the carbon media.

図・表・数式 / Figures, Tables and Equations

Figure 1 Overall morphological structure and component identifications of WH0.03 including (a) the TEM image of WH0.03, the TEM images of individual particles along with the corresponding SAED patterns of (b) Fe₃O₄ and (c) chlorapatite, and (d) the EDS mapping of main elements within WH0.03

Figure 2 Illustrations of carbon structure confirmation using TEM and spectroscopy: (a) TEM image of the carbon matrix in WH0.03, (b) examples of graphitic domains within the carbon region, (c) EELS spectrum of the carbon matrix, and (d) Raman spectra of WH0.03 compared to WH raw materials

Figure 3 SEM images of (a) polypyrrole, (b) RGO-SiO₂, (d, e) RGO-SiO₂@PPy; TEM images of (c) RGO-SiO₂, (f) RGO-SiO₂@PPy.

Figure 4 TEM images of RGO-SiO₂@PPy and corresponding elemental mapping images of C (carbon), N (nitrogen), O (oxygen), and Si (silicon)

Figure 5 TEM images corresponding to SAED patterns (inset) of pre-cycled (a, b) and post-cycled (d, e) PPy@Nano-SiO₂/C electrodes and particle size histograms of SiO₂ NPs (c) and Si QDs (f), HRTEM image of a single synthesized Si-NP (g) showing the (111) lattice (inset), HAADF-STEM image (h), and EDS elemental mapping images of PPy@Nano-SiO₂/C (i-l): overlay of C K edge (i), O K edge (j), Si K edge (k), and N K edge (l)

Figure 6 (a) TEM image with SAED pattern inset and (b) HRTEM image with lattice view of the carbon sheet of Nano-SiO₂/C nanocomposite

Figure 7 (a) bright field TEM image of SnO₂/C (b-c) High-resolution TEM images of the SnO₂/C (d-g) EDS mapping of the SnO₂/C

Figure 8 (a-c) dark field TEM images of the SnO₂&SnS₂/C sample (d-g) EDS mapping of the SnO₂&SnS₂/C sample

その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)

References
(1)           Xu, Z.; Zhang, Z.; Li, M.; Yin, H.; Lin, H.; Zhou, J.; Zhuo, S. Three-Dimensional ZnS/Reduced Graphene Oxide/Polypyrrole Composite for High-Performance Supercapacitors and Lithium-Ion Battery Electrode Material. Journal of Solid State Electrochemistry 2019, 23 (12), 3419–3428. https://doi.org/10.1007/s10008-019-04434-y.
(2)           Hsu, F. H.; Wu, T. M. In Situ Synthesis and Characterization of Conductive Polypyrrole/Graphene Composites with Improved Solubility and Conductivity. Synth Met 2012, 162 (7–8), 682–687. https://doi.org/10.1016/j.synthmet.2012.02.025.
(3)           Prasankumar, T.; Karazhanov, S.; Jose, S. P. Three-Dimensional Architecture of Tin Dioxide Doped Polypyrrole/Reduced Graphene Oxide as Potential Electrode for Flexible Supercapacitors. Mater Lett 2018, 221, 179–182. https://doi.org/10.1016/j.matlet.2018.03.093.
(4)           Xie, D.; Wang, D. H.; Tang, W. J.; Xia, X. H.; Zhang, Y. J.; Wang, X. L.; Gu, C. D.; Tu, J. P. Binder-Free Network-Enabled MoS2-PPY-RGO Ternary Electrode for High Capacity and Excellent Stability of Lithium Storage. J Power Sources 2016, 307, 510–518. https://doi.org/10.1016/j.jpowsour.2016.01.024.
(5)           Etacheri, V.; Marom, R.; Elazari, R.; Salitra, G.; Aurbach, D. Challenges in the Development of Advanced Li-Ion Batteries: A Review. Energy and Environmental Science. September 2011, pp 3243–3262. https://doi.org/10.1039/c1ee01598b.
(6)           Muruganantham, R.; Wang, F. M.; Liu, W. R. A Green Route N, S-Doped Hard Carbon Derived from Fruit-Peel Biomass Waste as an Anode Material for Rechargeable Sodium-Ion Storage Applications. Electrochim Acta 2022, 424 (February), 140573. https://doi.org/10.1016/j.electacta.2022.140573.   The authors would like to express their gratitude to the Renewable Energy Laboratory-Advanced Battery Research Unit, Chiang Mai University, for sample preparation, battery cell fabrication, and electrochemical measurements. Also, the authors appreciate the characterizations and facility supports provided by the Department of Chemistry, Faculty of Science, Chiang Mai University. Advanced electron microscopy was supported by the Collaborative Research Program of Institute for Chemical Research, Kyoto University [Grant No. 2022-127]. This research project was financially supported by Fundamental Fund 2022, Center of Excellence in Materials Science and Technology under the Administration of Materials Science Research Center of Chiang Mai University, the Postdoctoral Fellowships, Chiang Mai University, and Program Management Unit for Competitiveness (PMU-C), Office of National Higher Education Science Research and Innovation Policy Council.

成果発表・成果利用 / Publication and Patents

論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)

1. Natthakan Ratsameetammajak, Rice husk-derived nano-SiO₂assembled on reduced graphene oxide distributed on conductive flexible polyaniline frameworks towards high-performance lithium-ion batteries, RSC Advances, 12, 14621-14630(2022).
   DOI: 10.1039/D2RA00526C
   
2. Waewwow Yodying, Low-Cost Production of Fe3O4/C Nanocomposite Anodes Derived from Banana Stem Waste Recycling for Sustainable Lithium-Ion Batteries, Crystals, 13, 280(2023).
   DOI: 10.3390/cryst13020280
   

口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.

1. • K. Pimta, T. Autthawong, W. Yodying, C. Phromma, M. Haruta, H. Kurata, T. Sarakonsri and Y. Chimupala, ACS omega, 2023, Development of Bronze-phase Titanium Dioxide Nanorods for Use as Fast-charging Anode Materials in Lithium-ion Batteries. (Under revision)
2. • W. Yodying, T. Autthawong, O. Namsar, T. Kiyomura, M. Haruta, H. Kurata, T. Chairuangsri, and T. Sarakonsri, J. mater. Sci.: Mater. Electron., 2023, Recycling Water Hyacinth Stem Waste for Cost-Effective Production of Carbon/FeOx Nanocomposite Anodes for Sustainable Fast-Charging Lithium-Ion Batteries. (Submitted manuscript)
3. • Thapanee Sarakonsri, “Enhanced Electrochemical Performance of Sn(SnO2)/TiO2(B) Nano-composite Anode Materials with Ultrafast-Charging and Stable Cycling for High-Performance Li-Ion Batteries”, The 4th Thailand-Korea Symposium on Materials for Biomedical and Energy Applications, January 31, 2023.

特許 / Patents

特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件