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Tailoring the coordination environment of Co-Sn active sites via zinc aluminate spinel support for highly chemoselective hydrogenation of methyl oleate
(2027-01-01)
Sooknoi, Tawan
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Chanakha, Vichuda
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Wattanakul, Titiporn
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Ausavasukhi, Artit
The chemoselective hydrogenation of methyl oleate to oleyl alcohol was investigated over Co-Sn catalysts supported on zinc aluminate (ZnAl<inf>2</inf>O<inf>4</inf>). The ZA-M support, synthesized via a methanol-mediated solvothermal route, provided a high specific surface area (296.8 m2/g) and an optimized mesoporous structure. Sequential NaBH<inf>4</inf> and H<inf>2</inf> reduction finely tuned the coordination of active sites, enabling the optimized 2Co4SnBH/ZA-M catalyst to achieve a superior oleyl alcohol yield (33.58%) and a high selectivity (65.39%) at a conversion level of 51.36% via a direct hydrogenation pathway. Based on bulk and surface characterizations, a fraction of cobalt was found to remain in a cationic state, stabilized within a network of interfacial Co-O-Sn complexes and framework CoAl<inf>2</inf>O<inf>4</inf>. These species are proposed to function as bifunctional active centers, where the Snn+/Sn0 species and neighboring Co2+ sites cooperatively enhance the chemoselectivity toward C=O reduction. Furthermore, the optimized catalyst demonstrated reasonable structural stability and reusability over four cycles, maintaining its catalytic viability despite a minor extent of metal leaching. These findings underscore the efficacy of spinel-supported ionic-metallic ensembles for the highly chemoselective and efficient hydrogenation of long-chain fatty acid methyl esters.
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Silica-supported nanostructured copper phyllosilicate: Boosting stability, capacity, and conductivity of Li-ion battery Si-based anodes
(2026-11-01)
Shajan, Minnu Gemini
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Chou, Feng Yuan
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Prasanseang, Warot
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Yimtrakarn, Trakarn
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Sooknoi, Tawan
Explosive demand for large-scale rechargeable batteries has driven the search for alternative electrode materials with higher energy density, lower toxicity, lower cost, and more natural abundance. Si-based materials, e.g., Si, SiO, SiO<inf>2</inf>, and silicates have emerged as promising choices, with extremely high capacities from most cost-effective and abundant sources. However, these compounds still suffer from major issues, such as extreme volume change, poor cycling stability, high manufacturing costs, and low conductivity. Herein, we have prepared low-cost porous nanosized silica-supported copper phyllosilicate, x CuPS/SiO<inf>2</inf>, with different Cu loadings and investigated them as anode material in Li cells. Due to the highly dispersed Cu species strongly interacted with nanosphere SiO<inf>2</inf> support matrix, 20CuPS/SiO<inf>2</inf> has been found to deliver a capacity as high as ∼3550 mAh g‒1 at 500 mA g‒1 with an impressive capacity retention of 99% upon conversion reactions with Li+, and a reversible capacity of 2216 mAh g‒1 at 5000 mA g‒1. These values are among the highest ever reported for Si-, silicate-, silica-, and copper oxide-based anodes. Various phases, i.e., CuO, Li<inf>4</inf>SiO<inf>4</inf>, SiO, Si, Li<inf>2</inf>O, Cu, and Li<inf>x</inf>Si, are formed in the SiO<inf>2</inf> nanodomain, as confirmed by various ex situ characterization techniques, and the redox mechanism has been proposed. The components, particularly Li<inf>4</inf>SiO<inf>4</inf>, Li<inf>2</inf>O, and SiO<inf>2</inf>, are shown to help buffer volumetric or structural changes induced by the redox processes. The nanosized composite and the in situ -formed metallic Cu play a crucial role in rapid charge-transfer kinetics. These synergistic effects ultimately result in an unprecedented electrochemical performance of x CuPS/SiO<inf>2</inf> observed in this work.
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Structure–property relationships in Mg–Al hydrotalcites and derived mixed oxides for biomass conversion
(2026-09-01)
Lakhani, Pratikkumar
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Sooknoi, Tawan
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Kawi, Sibudjing
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Tomishige, Keiichi
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Srifa, Atthapon
Mg–Al hydrotalcites are prototypical layered double hydroxides whose physicochemical properties arise from highly tunable local atomic environments and reversible structural transformations. Derived from brucite-like layers of edge-sharing MgO<inf>6</inf> and AlO<inf>6</inf> octahedra, these materials exhibit adjustable layer charge density, controlled cation distribution, and chemically responsive interlayer galleries composed of anions and hydrogen-bonded water networks. Variations in Mg/Al ratio, interlayer composition, synthesis strategy, and post-synthesis treatments strongly influence local coordination geometry, defect density, acid-base site distribution, and surface reactivity. Upon thermal activation, hydrotalcites undergo topotactic transformation into homogeneous Mg–Al mixed metal oxides, generating coordinatively unsaturated metal centers, lattice defects, and a balanced ensemble of Brønsted basic and Lewis acidic sites. Notably, these oxides retain a structural memory effect, enabling partial reconstruction of the layered framework under aqueous or reactive environments and imparting dynamic adaptability to the local surface structure. This reversible interplay between layered and oxide states governs metal anchoring, electronic metal-support interactions, and stabilization of highly dispersed mono- and bimetallic active phases. This review examines Mg–Al hydrotalcites and their calcined derivatives from a structural and surface chemistry perspective, correlating synthesis-induced structural features, local coordination environments, and catalytic functionality using insights from advanced diffraction, spectroscopic, microscopic, and operando techniques. By correlating coordination structure with catalytic behavior, this article provides a unified framework for the rational design of Mg–Al hydrotalcite-based materials as versatile catalyst supports and multifunctional catalytic systems.
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Synergistic effects of bimetallic Co-SnOx species in selective hydrogenation of methyl oleate: The crucial role of reduction characteristics
(2026-09-01)
Sooknoi, Tawan
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Thainoi, Suwimon
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Chanakha, Vichuda
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Ausavasukhi, Artit
This study investigates the catalytic performance of bimetallic Co-Sn catalysts supported on alumina (Al<inf>2</inf>O<inf>3</inf>) for the selective hydrogenation of methyl oleate to oleyl alcohol. A strategic sequential reduction methodology, employing sodium borohydride followed by thermal hydrogen treatment (NaBH<inf>4</inf>-H<inf>2</inf>), was utilized to precisely tune the catalytic activity and chemoselectivity. Catalysts reduced solely with hydrogen at 300 °C exhibited limited efficiency, primarily favoring the formation of oleic acid via hydrogenolysis, which is attributed to the prevalence of cobalt oxide species. In contrast, the CoSnBH/Al<inf>2</inf>O<inf>3</inf> catalyst synthesized via a strategic sequential reduction methodology demonstrated a markedly enhanced selectivity toward oleyl alcohol, achieving a maximum selectivity of 54.1% at 270 °C and 8 MPa. Comprehensive characterization and kinetic analyses revealed that the superior performance stems from the synergistic coexistence of metallic cobalt (Co0) and low-valent tin oxides (SnO<inf>x</inf>), which form a bimetallic interface that preferentially polarizes the C=O bond. The catalytic efficiency was found to be highly sensitive to the nature of the support, the Co/Sn atomic ratio, and the total metal loading. Notably, turnover frequency (TOF) analysis indicated that while increased loading improves conversion, it may lead to site agglomeration and a reduction in surface-active concentration. Mechanistically, we propose that the CoSnBH/Al<inf>2</inf>O<inf>3</inf> system facilitates a direct hydrogenation pathway to oleyl alcohol, effectively bypassing the formation of heavy ester intermediates typically reported in literature.
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1H NMR-based machine learning methods for rapid authentication and composition profiling of crude palm oil
(2026-09-01)
Nggofur, Abdul
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Sueviriyapan, Natthapong
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Nuntawong, Noppadon
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Sutthiumporn, Ketsada
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Sooknoi, Tawan
A rapid analytical workflow for determining geographical origin and predicting fatty acid composition of crude palm oil (CPO) was developed using 1H NMR, GC-FID, and machine learning. Analyzing CPO samples from Indonesia, Malaysia, the Philippines, and Thailand using unsupervised fingerprinting with principal component analysis (PCA), t-distributed stochastic neighbor embedding (t-SNE), and uniform manifold approximation and projection (UMAP) revealed partial origin-based grouping. Supervised classification, validated via leave-one-out cross-validation (LOOCV) and uncertainty quantification (UQ), reliably discriminated the origins above random chance. Additionally, partial least squares regression (PLSR) accurately predicted oleic, linoleic and myristic acid levels measured by GC-FID, whereas the accuracy decreased for lauric, stearic and palmitic acids. PLSR reliability was rigorously validated using latent variable selection and permutation testing to rule out random correlations. Overall, this integrated 1H NMR and machine learning approach offers a rapid tool for CPO geographical traceability and compositional evaluation, demonstrating its potential for industrial quality control.
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Bifunctional WOx/SiO2 catalysts for hydrogen-free upgrading of B100 and bio-ethylene to SAF and green diesel precursors via olefin metathesis and deoxygenation
(2026-09-15)
Solehudin, Mochamad
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Wengwirat, Kanokwan
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Promchana, Pratya
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Poo-arporn, Yingyot
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Limphirat, Wanwisa
This work presents a hydrogen-free catalytic route for upgrading palm-derived biodiesel (B100) into olefinic precursors for sustainable aviation fuel (SAF) and green diesel (GD) using bifunctional WO<inf>x</inf>/SiO<inf>2</inf> catalysts under atmospheric pressure. The catalysts integrate olefin cross-metathesis, mediated by surface W CH<inf>2</inf> species, with deoxygenation via Lewis-acidic W O sites, enabling selective C C bond exchange and C O bond cleavage without external hydrogen or noble metals. Detailed mechanistic studies revealed that methyl oleate (MO) rapidly undergoes cross-metathesis with ethylene to yield SAF-range C<inf>9</inf>–C<inf>14</inf> precursors, while methyl palmitate (MP) contributes primarily to GD (C<inf>15</inf>–C<inf>18</inf>) through ketene intermediates and decarbonylation–hydrogen transfer pathways. Contact time and temperature experiments confirmed that MO conversion is kinetically favored at milder conditions, whereas MP-derived pathways dominate at higher temperatures and extended residence times. Catalyst loading studies show that the 3 and 5 wt% WO<inf>x</inf>/SiO<inf>2</inf> catalysts are dominated by highly dispersed isolated and polymeric WO<inf>x</inf> species, which exhibit higher accessible acidity and consequently promote secondary cracking reactions. In contrast, the 8 wt% WO<inf>x</inf>/SiO<inf>2</inf> catalyst contains a higher fraction of bulk crystalline WO<inf>3</inf> domains, resulting in reduced surface acidity and suppressed cracking. Overall, 8 wt% WO<inf>x</inf>/SiO<inf>2</inf> delivers reasonable rates with high selectivity toward SAF/GD precursors, while minimizing secondary cracking. It can be regenerated and recycled with substantial recovery of catalytic performance, establishing a robust, low-pressure, and hydrogen-free pathway for scalable renewable fuel production from B100.
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Dry-gel synthesis of Ti-beta for epoxidation of unsaturated fatty acid methyl esters (FAMEs)
(2026-09-01)
Yomthong, Krissanapat
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Saenluang, Kachaporn
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Soyphet, Asadawut
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Ittisanronnachai, Somlak
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Padchasri, Jintara
The Ti-beta was synthesized via a dry-gel conversion approach with the direct incorporation of titanium from titano-aluminosilicate nanobeads (Ti-SiAl-NB). At first, the Ti-SiAl-NB was prepared and employed as the precursor for zeolite crystallization. Powder XRD (PXRD) patterns confirm the amorphous nature of the nanobeads. These Ti-SiAl-NB precursors were subsequently converted to the Ti-beta zeolite via the dry-gel conversion approach. Structural characterization using PXRD, high-resolution TEM, and selected area electron diffraction (SAED) confirmed the formation of a beta zeolite framework, with dominant lattice planes indexed to (101) and (302). UV-vis DRS indicated that Ti existed as a tetrahedrally coordinated (TiIV) and non-framework Ti. Unfortunately, the as-synthesized Ti-beta exhibited a low catalytic activity in methyl oleate (MO) epoxidation, which is attributed to the prevalence of closed site TiIV [Ti(OSi)<inf>4</inf>] species that restrict substrate accessibility to active sites. To address this limitation, a post-synthetic treatment involving framework etching was applied to generate open site TiIV [Ti(OSi)<inf>3</inf>OH] species. As a result, MO conversion increased by approximately 2.73-fold, with epoxide selectivity up to 70%. Catalyst stability tests demonstrated sustained MO conversion of 65–72% and epoxide selectivity above 65% over several consecutive catalytic cycles. This work highlights a sustainable catalyst design strategy that combines the dry-gel conversion process with mild post-treatment to enhance active site accessibility and catalytic performance in the epoxidation of bulky molecules.
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Surface-Engineered Ru–Graphene Mesosponge Catalysts for pH-Universal and Seawater Hydrogen Evolution
(2026-06-17)
Sornnoei, Nichakarn
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Samantarkun, Naruewan
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Saisopa, Thanit
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Chavalekvirat, Panwad
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Iamprasertkun, Pawin
Efficient green hydrogen production from diverse water sources demands excellent catalysts that combine high activity, durability, and pH universality. Herein, we present a surface-engineered graphene mesosponge (GMS) uniformly decorated with ruthenium (Ru) nanoclusters as a robust electrocatalyst for the hydrogen evolution reaction (HER). The hierarchical GMS structure offers exceptional conductivity and mesoporosity, enabling nanoscale Ru dispersion and strong interfacial coupling. The obtained synergy of Ru50/GMS (optimized Ru deposition) delivers outstanding HER performance across pH range conditions, which provides overpotentials of ∼0.13 V and ∼0.061 V in acidic and alkaline electrolytes, respectively, close to those of the Pt electrode. Interestingly, Ru50/GMS achieves 10 mA cm–2 at only ∼0.39 V in neutral seawater, demonstrating robust operation under harsh, chloride-rich conditions. This performance is nearly 3-fold higher than that of pristine GMS, while sustaining accelerated kinetics and enhanced charge buffering. This is due to electronic modulation at the Ru–graphene interface via topological defects, which substantially optimized hydrogen adsorption and desorption, underpinning rapid reaction pathways. Furthermore, long-term operations confirm structural integrity and negligible catalyst degradation after 5000 cycles and 24 h at ultrahigh current density (−208 ± 10 mA cm–2), highlighting catalyst resilience for practical conditions. Therefore, this work demonstrates a scalable strategy for designing Ru-based catalysts on porous graphene supports, offering a compelling route for efficient, seawater-compatible green hydrogen production.
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Tailoring Re-loaded core–shell Ni structures embedded in mesoporous silica for the selective transformation of levulinic acid into γ-valerolactone
(2026-05-21)
Maneewong, Yupawan
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Lakhani, Pratikkumar
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Ratchahat, Sakhon
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Sakdaronnarong, Chularat
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Limphirat, Wanwisa
Heterogeneous core–shell catalysts have attracted significant interest because they integrate multiple catalytic functions within a single, precisely engineered architecture. In this work, we report the rational synthesis and catalytic evaluation of a Re-loaded Ni core–shell catalyst embedded in mesoporous silica for the efficient hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL). The core–shell configuration enables effective confinement of Ni nanoparticles within the porous silica matrix and stabilizes spatially separated Ni and ReO<inf>X</inf> species with complementary catalytic functions. Comprehensive physicochemical characterization confirmed the successful formation of the core–shell structure, its high structural stability, and the presence of confined metallic Ni sites responsible for H<inf>2</inf> activation and oxophilic ReO<inf>X</inf>-derived acid sites for oxygenate activation. Under optimized conditions, the Ni<inf>12</inf>Re<inf>1.63</inf>-CS catalyst achieved complete LA conversion with a GVL yield exceeding 94% within 2 h, outperforming non-core-shell catalysts. The catalyst also displayed high intrinsic activity, with a turnover frequency of up to ∼36 h−1, and retained an excellent GVL selectivity of approximately 80% during recycling, despite a gradual decrease in LA conversion. These findings demonstrate that spatial separation of hydrogenation and oxophilic adsorption sites within a core–shell architecture is critical for enhancing activity and selectivity in biomass-derived platform molecule upgrading.
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Hydroxylamine intermediate governs selectivity in nitrite hydrogenation on Pd-based catalysts for sustainable water treatment
(2026-05-07)
Betting, Janek
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Preedawichitkun, Yardthip
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Sooknoi, Tawan
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Lefferts, Leon
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Faria Albanese, Jimmy A.
Catalytic hydrogenation of nitrate (NO<inf>3</inf>−) and nitrite (NO<inf>2</inf>−) is a promising route for drinking water purification and rebalancing the global nitrogen cycle. Recently, hydroxylamine (NH<inf>2</inf>OH) was detected as a persistent reaction intermediate although ammonium (NH<inf>4</inf>+) and dinitrogen (N<inf>2</inf>) were assumed to be the only significant reaction products for several decades. In this work, we systematically investigate NO<inf>2</inf>− hydrogenation over Pd/Al<inf>2</inf>O<inf>3</inf> and SnPd/Al<inf>2</inf>O<inf>3</inf> while explicitly quantifying NH<inf>2</inf>OH under various conditions, including changes in H<inf>2</inf> partial pressure, the initial NO<inf>2</inf>− concentration, and reaction temperature, and through co-feeding of NH<inf>2</inf>OH. We reveal that NH<inf>4</inf>+ selectivity depends strongly on the NO<inf>2</inf>− conversion level, reflecting shifts in surface coverages as the reaction progresses. Suppression of both NH<inf>2</inf>OH and NH<inf>4</inf>+ formation is only achievable under H<inf>2</inf>-deficient conditions, though this comes at the expense of lower overall hydrogenation activity. Elevated temperatures enhance NH<inf>2</inf>OH decomposition and thereby promote NH<inf>4</inf>+ formation, while leaving N<inf>2</inf> selectivity largely unaffected. Co-feeding experiments further show that externally introduced NH<inf>2</inf>OH does not influence the NO<inf>2</inf>− hydrogenation rate. We critically reviewed prior mechanistic studies on NO<inf>2</inf>− hydrogenation and propose a refined Langmuir–Hinshelwood scheme that explicitly incorporates NH<inf>2</inf>OH as a desorbed intermediate. This work highlights the importance of NH<inf>2</inf>OH in the reaction network and underscores the need to include it in the assessment of the reaction selectivity.

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