1. Dynamic ferrous iron regeneration enables stabilization of NiFeCo layered double hydroxide for enhanced alkaline water oxidation
Samutr Assavachin a, Somlak Ittisanronnachai b, Thassanant Atithep b, Nattamon Chitterisin b, Montree Sawangphruk.
Journal of Power Sources, 2025, 650, 237494.
Impact Factor : 8.1, CiteScore : 16. 4.
DOI : 10.1016/j.jpowsour.2025.237494
Abstract : Nickel–iron layered double hydroxides (NiFe LDH) are cost-effective and high-performance electrocatalysts for the oxygen evolution reaction (OER) comparable to noble metals. However, their stability is hindered by Fe leaching under oxidative alkaline conditions, resulting in catalyst deactivation. This work proposes to address the limited stability of NiFe LDH by introducing cobalt doping and Fe2+ ions into the electrolyte. Cobalt enhances the catalytic activity and facilitates the oxidation of Fe2+ to Fe3+ to replenish the Fe active sites lost during OER. Electrochemical tests demonstrate that NiFeCo LDH achieves a lower overpotential of 209 mV at 10 mA cm−2 and improved kinetics (Tafel slope of 86 mV dec−1) compared to NiFe LDH (287 mV at 10 mA cm−2, Tafel slope of 170 mV dec−1). Stability test shows NiFeCo LDH maintains activity for over 120 h with 0.1 mM Fe2+, whereas NiFe LDH deactivates after 35 h. ICP-OES confirms stable Fe concentrations in NiFeCo LDH with Fe2+ addition, unlike in NiFe LDH where Fe concentration decreases over long-term operation. This approach of Fe regeneration via cobalt-catalyzed oxidation extends the lifetime of NiFeCo LDH in alkaline electrolysis up to 120 h enhancing the stability of NiFe-based OER catalysts for long-term applications.
2. Optimized Tap Density of Low-Cost Activated Carbon for HighPerformance Supercapacitors in 18650 Cylindrical Cells
Ronnachai Songthan, Thitiphum Sangsanit, Nuttida Matkhaw, Surat Prempluem, Phatsawit Wuamprakhon, Worapol Tejangkura and Montree Sawangphruk.
Journal of The Electrochemical Society, 2025.
Impact Factor : 3.1, CiteScore : 8.0, H-index : 310
DOI: 10.1149/1945-7111/addd6b
Abstract : The high cost of supercapacitors relative to lithium-ion batteries is primarily attributed to the expensive activated carbon (AC) materials used in their electrodes, which can cost as much as $170–500 per kg. This study presents a cost-effective alternative by utilizing large-pellet, water filtration-grade granular activated carbon (WFG-AC) (~$6 per kg) as an electrode material for 18650 cylindrical supercapacitor cells. Through a systematic optimization process involving ball milling, Mechano-Fusion, and annealing, we tailored WFG-AC to enhance its tap density, particle morphology, and control its oxygen content as low as possible. Unlike conventional approaches that prioritize high specific surface area, our findings reveal that tap density is the dominant factor governing electrochemical performance in volume-constrained supercapacitor designs. Despite a moderate specific surface area (886 m²/g), WFG-AC demonstrates a high cell capacitance of 105.72 F and remarkable cycling stability (84.55% retention after 120,000 cycles), matching the performance of high-surface-area commercial ACs. These results establish WFG-AC as a scalable, cost-effective, and high-performance electrode material, providing a paradigm shift in supercapacitor electrode design while significantly reducing manufacturing costs.
3. Stable Solid Electrolyte Interphase in Cylindrical Anode-Free Li-Metal NMC90 Batteries with Li2NiO2 Prelithiation and Fluorine-Rich Electrolytes for High Energy Density
Thitiphum Sangsanit, Nuttida Matkhaw, Ronnachai Songthana, Phatsawit Wuamprakhon, Worapol Tejangkura, Montree Sawangphruk.
Nano Letters, 2025. (Nature index)
Impact Factor : 9.6, Q1, CiteScore : 16.8, H-index : 569.
DOI: 10.1021/acs.nanolett.5c01595
Abstract : This study advances anode-free lithium-metal batteries (AFLMBs) by integrating nickel-rich NMC90 cathodes and fluorine-rich electrolytes in large-format 18650 cylindrical cells. A key innovation is the incorporation of 10 wt % Li-rich Li2NiO2 as a prelithiation agent in the cathode, which mitigates initial lithium-loss and improves the Coulombic efficiency. The electrolyte includes 30% (v/v) fluoroethylene carbonate (FEC) as a cosolvent, which suppresses inactive lithium deposition and stabilizes the solid electrolyte interphase (SEI). Unlike conventional AFLMBs that require external pressure, this work uses a stainless-steel casing with a tailored jelly roll configuration to mechanically regulate lithium plating. The optimized cells deliver an energy density of 320 Wh/kg, maintain stable cycling over 140 cycles, and support 4C-rate operation. Post-mortem analysis reveals a LiF-rich SEI that extends the cycle life, while operando X-ray diffraction provides insights into structural evolution. This research offers a scalable strategy for high-energy AFLMBs through the synergy of prelithiation, electrolyte design, and mechanical stabilization.
4. New materials for lithium–sulfur batteries: challenges and future directions
Montree Sawangphruk.
Chemical Communications, 2025. (Nature index)
Impact Factor : 4.3, Q1, (87th), CiteScore : 8.6, H-index : 387.
DOI: 10.1039/D5CC01150G
Abstract : This review explores recent advances in lithium–sulfur (Li–S) batteries, promising next-generation energy storage devices known for their exceptionally high theoretical energy density (∼2500 W h kg−1), cost-effectiveness, and environmental advantages. Despite their potential, commercialization remains limited by key challenges such as the polysulfide shuttle effect, sulfur's insulating nature, lithium metal anode instability, and thermal safety concerns. This review provides a comprehensive and forward-looking perspective on emerging material strategies—focusing on cathode, electrolyte, and anode engineering—to overcome these barriers. Special emphasis is placed on advanced sulfur–carbon composites, including three-dimensional graphene frameworks, metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and MXene-based materials, which have demonstrated significant improvements in sulfur utilization, redox kinetics, and cycling stability. Innovations in electrolytes—particularly solid-state and gel polymer systems—are discussed for their roles in suppressing polysulfide dissolution and enhancing safety. This review also examines lithium metal anode protection strategies, such as use of artificial SEI layers and 3D lithium scaffolds and lithium alloying. Finally, it discusses critical issues related to large-scale manufacturing, safety, and commercial scalability. With ongoing innovation in multifunctional materials and electrode design, Li–S batteries are well positioned to transform energy storage for electric vehicles, portable electronics, and grid-scale systems.
5. Advancing safer and sustainable Supercapacitors: First demonstration of water-in-salt electrolytes in 18650 cylindrical cells
Thitiphum Sangsanit, Nuttida Matkhaw, Ronnachai Songthana, Phatsawit Wuamprakhon, Worapol Tejangkura, Montree Sawangphruk.
Journal of Power Sources, 2025, 237152.
Impact Factor : 8.1, CiteScore : 16.4.
DOI : 10.1016/j.jpowsour.2025.237152
Abstract : Supercapacitors provide high power density and long cycle life but face safety challenges due to the flammability and toxicity of acetonitrile (ACN)-based electrolytes. Water-in-Salt Electrolytes (WiSEs), such as 21m LiTFSI, offer a safer and more sustainable alternative but are limited by water-splitting reactions and voltage instability. This study presents the first demonstration of WiSE integration in practical 18650 cylindrical supercapacitors, optimizing separator selection and operating conditions to enhance performance and safety. In situ differential electrochemical mass spectrometry (DEMS) and nuclear magnetic resonance (NMR) spectroscopy reveal that cellulose separators effectively suppress hydrogen evolution reactions (HER), reducing gas evolution and electrolyte degradation, thereby improving long-term stability. WiSE-based cells operate stably at 2.1V and 2.3V, achieving over 80 % capacitance retention after 50,000 cycles at 2000 mA, demonstrating comparable durability to ACN-based systems. Additionally, WiSE-based supercapacitors exhibit superior thermal stability, remaining non-flammable and stable up to 250 °C, whereas ACN ignites instantly. This study represents a critical advancement in aqueous electrolyte supercapacitor technology, demonstrating that separator engineering and electrolyte formulation can significantly enhance stability. These findings provide a foundation for the practical deployment of safer, non-flammable supercapacitors in aerospace, medical, and industrial energy storage applications, where operational safety is paramount.
6. Ferroelectric BiFeO3 and BaTiO3 photocatalysts for photoelectrochemical water splitting
Samutr Assavachin, Montree Sawangphruk and Frank E Osterloh
Current Opinion in Chemical Engineering, 2025, 48, 101123.
Impact Factor : 8.0, CiteScore :12.8.
DOI : 10.1016/j.coche.2025.101123
Abstract : Photocatalytic water splitting offers a sustainable route for hydrogen production but is often hindered by rapid charge carrier recombination and slow kinetics. Traditional strategies to enhance charge separation include solid–solid junctions, facet engineering, and cocatalyst addition. This review explores an alternative approach using ferroelectric materials to improve photoelectrochemical (PEC) water splitting efficiency. Ferroelectric materials exhibit spontaneous electric polarization, generating internal electric fields that modulate band bending at the solid–liquid interface. This intrinsic property enhances charge carrier separation and directs photogenerated electrons and holes toward specific redox sites or cocatalysts. We highlight key studies demonstrating the effectiveness of ferroelectric materials in PEC applications. Electric polarization of BiFeO3 thin films resulted in controlled enhancement of water oxidation by directly influencing band bending and charge transfer processes. Similarly, BaTiO3–TiO2 core–shell structures with Ni(OH)₂ cocatalysts exhibited improved PEC activity through polarization-mediated charge separation. BaTiO3 particles also demonstrated enhanced PEC water oxidation and hydrogen evolution in both film and suspension systems due to ferroelectric effects. These findings underscore the potential of ferroelectric materials to optimize charge carrier dynamics in photocatalytic processes for better solar energy conversion.
7. Correlation Between Electrolyte Degradation Products and Overcharging Voltages in Supercapacitors
Ronnachai Songthan, Jiraporn Phojaroen, Thitiphum Sangsanit, Phatsawit Wuamprakhon, Worapol Tejangkura and Montree Sawangphruk
Journal of The Electrochemical Society, 2025, 172, 040509.
Impact Factor : 3.1, CiteScore : 8.0, H-index : 310
DOI : 10.1149/1945-7111/adc6c5
Abstract : This study systematically investigated the correlation between electrolyte decomposition products and overcharging voltages in cylindrical acetonitrile-based supercapacitors. Using a combination of gas chromatography-mass spectrometry, nuclear magnetic resonance, and thermogravimetric analyses, we identified acetamide as a primary degradation marker, forming at voltages as low as 2.7 V and reaching peak concentration at 3.5 V before undergoing further transformation into N-ethyl acetamide and trimethylsilyl acetamide. Notably, at ≥3.9 V, trimethylsilyl acetamide becomes the dominant by-product due to interactions with silicon impurities in activated carbon electrodes, accelerating degradation mechanisms. These decomposition pathways significantly impair supercapacitor performance, leading to a reduction in capacitance, coulombic efficiency, and energy efficiency by diminishing the effective surface area of the electrode. Furthermore, trace water generated at elevated voltages exacerbates these degradation reactions, further compromising stability. This work underscores the critical role of electrolyte purity and electrode material composition in mitigating performance deterioration. The findings provide fundamental insights into voltage-dependent degradation mechanisms, offering strategies to enhance the longevity, efficiency, and reliability of acetonitrile-based supercapacitors for high-power energy storage applications.
8. Different Impacts of Dissolved Transition Metals on the Graphite Anode in Lithium-Ion Batteries
Panyawee Bunyanidhi, Animesh Dutta, Toby Bond, Jigang Zhou, Jian Wang, Ben Tang, Divya Rathore, William Black, Montree Sawangphruk, Jeff R Dahn and Chongyin Yang
Journal of The Electrochemical Society, 2025, 172, 040506.
Impact Factor : 3.1, CiteScore :7.2, H-index : 310
DOI : 10.1149/1945-7111/adc511
Abstract : The dissolution of transition metals (TM) from the cathode and their subsequent deposition on the anode represent significant degradation mechanisms in lithium-ion batteries, particularly as the industry seeks to transition towards more sustainable and cost-efficient materials. In this work, the impacts of Mn, Fe, Ni, and Co depositions on the lithiated graphite anode were investigated using pouch storage experiments to simulate the migration-deposition process and compare it to electrodes from real cells. The morphology, chemical distribution, and oxidation states of deposited TMs were investigated by scanning electron microscopy, X-ray absorption spectroscopy, and scanning transmission X‐ray microscopy. X-ray diffraction and half-cell studies for post-storage electrodes determined the lithium loss and impedance growth due to TM deposition. The impact of each TM on the lithiated graphite was found to be significantly different. Deposited Mn and Fe were fully metallic, preferred to accumulate on electrode surface, and caused severe delithiation of the graphite, while Ni and Co deposition were rather harmless. The results obtained from simulated TM-containing graphite electrodes closely corresponded with those extracted from cycled cells. This alignment enhances our understanding of the behavior of dissolved TM and paves the way for solutions aimed at mitigating capacity fade in commercial lithium-ion batteries.
9. Fluorinated Electrolytes for High-Energy Ni-rich NCA90 Lithium-Ion Batteries at a Cylindrical Cell Configuration: A Deep Dive into Decomposition Pathways
Kan Homlamai, Thitiphum Sangsanit, Ronnachai Songthan, Worapol Tejangkura, and MontreeSawangphruk
ChemSusChem 2025, e202500238
Impact Factor : 7.5, CiteScore : 15.8
DOI : 10.1002/cssc.202500238
Abstract : This study investigates the electrochemical performance, stability, and decomposition mechanismsof fluorine-based electrolytes in large-scale cylindrical Ni-rich lithium-ion batteries (LIBs) underhigh-voltage conditions (up to 4.8 V). We examine fluoroethylene carbonate (FEC) and di-fluoroethylene carbonate (DFEC) in electrolyte formulations and their effects on battery longevity,gas evolution, and solvation dynamics. While FEC is known for improving the solid electrolyteinterphase (SEI), DFEC remains underexplored. Using molecular dynamics (MD) simulations,density functional theory (DFT) calculations, and electrochemical analysis, we identify keysolvation properties, ion transport characteristics (tLi⁺, CIP%), and electronic structuresinfluencing electrolyte stability. The 1.2 M LiPF₆ in DMC/FEC/DFEC (4:0.5:0.5% v/v) electrolyte achieves the highest capacity retention (85.11% after 1,000 cycles), with DFEC reducing solvationshell binding energy and stabilizing electrolyte performance. Differential electrochemical massspectrometry (DEMS) and nuclear magnetic resonance (NMR) spectroscopy reveal that FEC leadsto higher CO₂ production via ring-opening and de-fluorination to vinylene carbonate (VC), whileDFEC reduces gas evolution. These insights provide a holistic framework for optimizing high-energy electrolyte formulations, supporting the development of safer, more efficient LIBs forelectric vehicles and energy storage applications.
10. Layered lithium- and manganese-rich oxide cathode cells in large-scale cylindrical configuration: Optimized electrolyte formulations with LiDFOB and LiBF₄ Co-additives for enhanced stability
Thitiphum Sangsanit, Nuttida Matkhaw, Nurulsafeelanaria Benwannamas, Ronnachai Songthan, Worapol Tejangkura, Montree Sawangphruk
Journal of Power Sources, 2025, 632, 236337.
Impact Factor : 8.1, CiteScore : 16.4
DOI : 10.1016/j.jpowsour.2025.236337
Abstract : Layered lithium- and manganese-rich oxide (LMR-NMC) cathodes are emerging as frontrunners for next-generation lithium-ion batteries, offering exceptional specific capacities (>245 mAh/g) and high operating voltages (>4.7 V). However, their widespread adoption is hindered by severe electrolyte decomposition, exacerbated by lattice oxygen release and high voltage cycling, especially in large-scale cylindrical cells with thick electrodes. In this study, we provide the first comprehensive analysis of gas- and liquid-phase electrolyte decomposition in LMR-NMC//graphite 18650 cylindrical cells. We identify ethylene carbonate (EC)-induced degradation pathways, including excessive water generation during initial cycling, driven by reactions with active oxygen. To address these challenges, we propose an EC-free electrolyte formulation incorporating lithium difluoro(oxalato)borate (LiDFOB) and lithium tetrafluoroborate (LiBF₄) as co-additives. These additives effectively stabilize the cathode-electrolyte interphase (CEI), suppress oxygen-induced degradation, and dramatically enhance long-term cell stability. This optimized electrolyte design paves the way for scalable, high-energy LMR-NMC cathodes in commercial lithium-ion battery applications.
11. Investigation of Capacitance Degradation in Activated Carbon Supercapacitors Subjected to Cryogenic Conditions
Apichanont Limsukhon, Thitiphum Sangsanit, Worapol Tejangkura, Adisorn Tuantranont and Montree Sawangphruk
Journal of The Electrochemical Society, 2025, 172, 010515.
Impact Factor : 3.1, CiteScore :7.2, H-index : 310
DOI : 10.1149/1945-7111/ada73f
Abstract : This study examined the electrochemical performance of 18650 cylindrical supercapacitors subjected to a cryogenic temperature at −196 °C. Cylindrical supercapacitor cells, utilizing 1 M tetraethylammonium tetrafluoroborate (TEABF4) in acetonitrile as the electrolyte, were immersed in liquid nitrogen. Results indicated a 6.4% decrease in capacitance following exposure. To identify the cause of this reduction, we analyzed the surface chemistry of the electrodes and electrolyte degradation using X-ray photoelectron spectroscopy and proton nuclear magnetic resonance (¹H NMR), respectively. No significant changes were detected in either the surface chemistry or electrolyte. Instead, the capacitance reduction was linked to the higher activation energy required for electric double-layer adsorption/desorption, as described by the Arrhenius equation. This effect is attributed to the deformation of the styrene-butadiene rubber (SBR) binder because −196 °C is much lower than its glass transition temperature of −50 °C. At −196 °C, the SBR transitions from a flexible, rubbery state to a brittle, glassy state can cause the SBR to crack or shatter, thereby reducing the adhesive contact between the current collector and the active materials. These findings highlight the importance of polymer binders in ensuring long-term stability, especially for supercapacitors intended for low-temperature environments.
12. Microbubble synthesis of hybridised bacterial cellulose–gelatin separators for multifunctional supercapacitors
Surachai Chaichanaa, Pawin Iamprasertkun bc, Montree Sawangphruk d, Noelia Rubio e and Pichamon Sirisinudomkit
Sustainable Energy Fuels, 2025,9, 1745-1754
Impact Factor : 5.0, CiteScore : 10.0, H-index : 89.
DOI : 10.1039/d4se01684j
Abstract : Separators are known to be a mandatory component due to their crucial function in preventing short circuits between positive and negative electrodes, ensuring the safety and cycle life of energy storage devices. However, in practice, separators are a crucial component that affects cell electrochemical performance, especially rate capability and power density, which have been addressed in only a few research studies. To further investigate this topic, this study introduces durable and eco-friendly separators synthesised by hybridising bacterial cellulose (BC) and gelatin through a facile, cost-effective, desirable and environmentally friendly microbubble process. The as-fabricated symmetric supercapacitor with an as-synthesised separator, prepared under optimal conditions of 2 g per mL BC with 1.5 wt% gelatin and a microbubble rate of 200 CC per min (designated as 2BC1.5GT_R200), reduces cell resistance and optimises ion transport within the cell compared to as-fabricated symmetric supercapacitors using BC, hybridised BC–gelatin under other conditions, conventional cellulose and commercial separators. Additionally, symmetric devices with 2BC1.5GT_R200 separators achieve excellent capacitance retention across a wide range of electrolyte environments, including acidic (1 M H2SO4), basic (1 M KOH), and neutral (1 M NaNO3) solutions, retaining over 91%, 87%, and 82% of their initial capacitance after 10 000 cycles, respectively. These data demonstrate that the microbubble synthesis process combined with gelatin hybridisation can maximise electrochemical performance, maintain high cell efficiency, and enable operation in diverse electrolytes, presenting a promising route for developing innovative separators for energy storage applications.