Pongtanawat Khemthong

Mercury removal from aqueous and hydrocarbon media requires sorbents that combine strong binding affinity with sufficient pore accessibility and mass transfer. In this study, granular activated carbon (GAC) was treated with 1,2-ethanedithiol through an oxidant-free, thermally initiated thiol–ene-type radical route to produce sulfur-functionalized GAC (S-GAC) with different sulfur loadings. The sulfur content increased from 3.38 to 15.07 wt %, while the BET specific surface area decreased from 859 to 25 m2 g–1, indicating progressive pore occupation and blockage. At low initial Hg(II) concentration, sulfur functionalization enhanced Hg(II) removal in both aqueous solution and synthetic gas condensate, with 10–30%S-GAC achieving very low residual Hg(II) concentrations. At elevated aqueous Hg(II) concentrations, pristine GAC exhibited faster initial uptake and approached a plateau earlier, whereas S-GAC showed slower but sustained adsorption. At approximately 40 mg L–1 Hg(II) concentration, 5%S-GAC and 10%S-GAC ultimately achieved slightly higher observed uptakes than pristine GAC, while at approximately 120 mg L–1 pristine GAC retained the highest uptake over the monitored period. These results show that the effect of sulfur functionalization depends on Hg(II) loading, contact time, and the balance between Hg–S affinity and pore accessibility. XPS, Hg L3-edge XAS, and DFT calculations were consistent with sulfur-containing Hg coordination environments and more favorable interaction near sulfur-rich edge configurations. Sulfur functionalities remained strongly retained over pH 2–10, although regeneration performance decreased with repeated cycles. Overall, Hg(II) capture reflects the combined effects of sulfur-site affinity, pore accessibility, mass transfer, Hg(II) loading, and the treatment matrix.

Sustainable conversion of agricultural residues into functional nanomaterials offers new opportunities for biomass valorization and advanced biomedical applications. Herein, we report a single‐feedstock strategy for converting rice husk into cellulose nanocrystals (CNCs) and lysine‐doped carbon dots (L‐CDs), followed by their integration into a hybrid nanocarrier system. CNCs were obtained through alkali bleaching and sulfuric acid hydrolysis, while L‐CDs were synthesized via hydrothermal carbonization with in situ lysine doping. The resulting CNC/L‐CD hybrid exhibited excitation‐dependent photoluminescence, enhanced thermal stability, altered surface charge, and an increased optical bandgap (4.91 eV). Spectroscopic and surface analyses confirmed successful hybrid formation through electrostatic and hydrogen bonding interactions. To evaluate drug delivery performance, the CNC/L‐CD hybrid was incorporated into sodium alginate (SA) beads for tetracycline loading and release studies. SA‐CNC beads showed the highest tetracycline loading capacity (7.56 mg g ⁻¹ ), whereas SA‐CNC/L‐CD beads exhibited enhanced pH‐responsive release behavior under physiologically relevant conditions. The released tetracycline retained antibacterial activity against Escherichia coli , Staphylococcus aureus , and Salmonella typhimurium . Control experiments confirmed that unloaded carrier materials exhibited no intrinsic antibacterial activity. These findings demonstrate the potential of rice husk‐derived CNC/L‐CD hybrids as sustainable nanocarriers for pH‐responsive tetracycline delivery and highlight a practical route for transforming agricultural waste into value‐added biomedical materials.

Graphene functionalization tunes Li ⁺ mobility and mechanical strength in PEO-based solid polymer electrolytes through interfacial interactions, enabling tailored ionic conductivity and mechanical performance.

Catalytic upgrading of acetone–butanol–ethanol (ABE) mixtures provides a route to higher-value oxygenates for chemicals and fuel precursors. Here, Ni-, Ru-, and Ni–Ru-loaded ZIF-8 catalysts were prepared and evaluated for ABE upgrading, with particular emphasis on C7 oxygenate formation and the roles of reductive activation and acid–base properties. In situ Ni K-edge X-ray absorption spectroscopy showed that Ru facilitated Ni reduction during H₂ activation, while CO₂-TPD indicated increased basicity upon Ni incorporation. Among the activated catalysts, bimetallic 4Ni2RuZ8_act gave the highest 2-heptanone yield, exceeding the combined yields of the corresponding monometallic catalysts and suggesting a synergistic Ni–Ru effect. A pathway involving n-butanol dehydrogenation, C–C coupling with acetone-derived species to form 3-hepten-2-one, and subsequent hydrogenation to 2-heptanone was proposed. At 240 °C for 20 h using 20 mg of catalyst, 4Ni2RuZ8_act achieved 61.8% acetone conversion and produced 432 µmol of 2-heptanone. Reuse decreased both values by approximately 20%, accompanied by partial ZIF-8 degradation and ZnO formation. These results demonstrate the potential of multifunctional Ni–Ru/ZIF-8 catalysts for ABE upgrading toward C7 oxygenates while identifying structural stability as a key challenge for further development.

Cu‐metalated MOFs, particularly Zr‐based frameworks, are promising CO ₂ hydrogenation catalysts. Tuning Cu nuclearity toward small clusters or isolated atoms is crucial for controlling product selectivity, yet very challenging. One way to achieve this is by adjusting the number of OH/H ₂ O pairs on Zr ₆ nodes. While the UiO‐66 framework allows only one anchoring pair per node, the MOF‐808 can host up to six defects via formate substitution, enabling much higher Cu loadings (Cu/Zr ₆ up to 5.2). In addition, we found that the Cu precursor influences Cu nuclearity in MOFs: CuCl ₂ forms mainly isolated sites (Cu ₁ ), whereas Cu(NO ₃ ) ₂ promotes clusters (Cu _x ). Cu _x /MOF catalysts were examined for CO ₂ hydrogenation at the gas/solid and at liquid(gas)/solid interfaces. At the gas/solid interface, Cu _x /MOF catalysts showed higher activity and selectivity toward methanol, with Cu _x /UiO‐66 outperforming the Cu _x /MOF‐808 catalyst, while Cu ₁ /MOFs were barely active toward CH ₄ and CO formation. In the liquid phase, both Cu _x /MOF catalysts were active only for methanol formation. These results, together with detailed structural characterizations using X‐ray absorption and diffuse reflectance FTIR spectroscopy during pretreatment and CO ₂ reduction, electron microscopy, and a number of basic characterizations (N ₂ adsorption, PXRD, DR‐UV‐vis, thermal analyses, and NMR spectroscopy), are discussed in relation to the structure‐reactivity relationships, and are supported by DFT modeling of the Cu _x ensembles in both frameworks.

Cu–Ag alloy interfaces enable efficient CO spillover and local CO enrichment on Cu sites, creating a unique interfacial microenvironment that promotes acetate formation, whereas metallic Cu mainly produces ethylene and ethanol.