Dataset Information

Finding Key Factors for Efficient Water and Methanol Activation at Metals, Oxides, MXenes, and Metal/Oxide Interfaces.

ABSTRACT: Activating water and methanol is crucial in numerous catalytic, electrocatalytic, and photocatalytic reactions. Despite extensive research, the optimal active sites for water/methanol activation are yet to be unequivocally elucidated. Here, we combine transition-state searches and electronic charge analyses on various structurally different materials to identify two features of favorable O-H bond cleavage in H₂O, CH₃OH, and hydroxyl: (1) low barriers appear when the charge of H moieties remains approximately constant during the dissociation process, as observed on metal oxides, MXenes, and metal/oxide interfaces. Such favorable kinetics is closely related to adsorbate/substrate hydrogen bonding and is enhanced by nearly linear O-H-O angles and short O-H distances. (2) Fast dissociation is observed when the rotation of O-H bonds is facile, which is favored by weak adsorbate binding and effective orbital overlap. Interestingly, we find that the two features are energetically proportional. Finally, we find conspicuous differences between H₂O/CH₃OH and OH activation, which hints toward the use of carefully engineered interfaces.

SUBMITTER: Su HY

PROVIDER: S-EPMC8788388 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Finding Key Factors for Efficient Water and Methanol Activation at Metals, Oxides, MXenes, and Metal/Oxide Interfaces.

Su Hai-Yan HY Sun Keju K Gu Xiang-Kui XK Wang Sha-Sha SS Zhu Jing J Li Wei-Xue WX Sun Chenghua C Calle-Vallejo Federico F

ACS catalysis 20220105 2

Activating water and methanol is crucial in numerous catalytic, electrocatalytic, and photocatalytic reactions. Despite extensive research, the optimal active sites for water/methanol activation are yet to be unequivocally elucidated. Here, we combine transition-state searches and electronic charge analyses on various structurally different materials to identify two features of favorable O-H bond cleavage in H<sub>2</sub>O, CH<sub>3</sub>OH, and hydroxyl: (1) low barriers appear when the charge ...[more]

PMID: 35096469

Similar Datasets

Project description:The primary requirement for electrode materials in direct methanol fuel cells (DMFC) is efficient electrocatalyst that exhibit high tolerance to methanol oxidation, excellent stability, and reasonable cost. The combination of distinct active materials with distinctive architectures may facilitate the attainment of this objective. The present study included the preparation of a Carbon Xerogel Doped with various metal oxides derived from Banana peels. The nanocomposites were thoroughly examined utilizing several characterization modalities including XRD, FTIR, and SEM. The electrocatalytic performance of Carbon xerogel doped with Iron (Fe3O4/CX), carbon xerogel doped with magnesium (MgO/CX), and carbon xerogel doped with Copper (CuO/CX) about the Methanol Oxidation Reaction (MOR) was investigated using electrochemical methods such as cyclic voltammetry, impedance spectroscopy, and chronoamperometry. The results showed that the Fe3O4/CX, MgO/CX, and CuO/CX are effective electrocatalysts with an onset potential of around 1.00 V and current densities of approximately 42.98 mA cm - 2, 28.2784 mA.cm - 2, and 6.60698 mA.cm - 2, respectively, in the optimized electrolyte for methanol oxidation. The stability of Fe3O4/CX, MgO/CX, and CuO/CX electrodes was examined using chronoamperometry and the Cyclic Stability method. The results revealed that the (Fe3O4/CX) electrode exhibited outstanding stability throughout the whole 60-minute chronoamperometry Technique and demonstrated great stability for 100 cycles in the Cyclic Stability technique. The remarkable electrochemical activity and stability may be attributed to the synergistic effect of Fe3O4/CX, which provided sufficient active sites for methanol electro-oxidation and reduced the equivalent series resistance, as shown by the electrochemical impedance spectroscopy analysis. This work used environmentally friendly materials, which presents a novel opportunity to enhance the efficiency of methanol oxidation via the utilization of affordable catalysts. This study of the theoretical technique methods for establishing the route of methanol decomposition, and systematizes their confirmation with experimental data, within the methodological framework.

Project description:In soil metal ecotoxicology research, dosing is usually performed with metal salts, followed by leaching to remove excess salinity. This process also removes some metals, affecting metal mixture ratios as different metals are removed by leaching at different rates. Consequently, alternative dosing methods must be considered for fixed ratio metal mixture research. In this study three different metal mixture dosing methods (nitrate, oxide and annealed metal dosing) were examined for metal concentrations and toxicity. In the nitrate metal dosing method leaching reduced total metal retention and was affected by soil pH and cation exchange capacity (CEC). Acidic soils 3.22 (pH 3.4, CEC 8 meq/100g) and WTRS (pH 4.6, CEC 16 meq/100g) lost more than 75 and 64% of their total metals to leaching respectively while Elora (6.7 pH, CEC 21 meq/100g) and KUBC (pH 5.6, CEC 28 meq/100g) with higher pH and CEC only lost 13.6% and 12.2% total metals respectively. Metal losses were highest for Ni, Zn and Co (46.0%, 63.7% and 48.4% metal loss respectively) whereas Pb and Cu (5.6% and 20.0% metal loss respectively) were mostly retained, affecting mixture ratios. Comparatively, oxide and annealed metal dosing which do not require leaching had higher total metal concentrations, closer to nominal doses and maintained better mixture ratios (percent of nominal concentrations for the oxide metal dosing were Pb = 109.9%, Cu = 84.6%, Ni = 101.9%, Zn = 82.3% and Co = 97.8% and for the annealed metal dosing were Pb = 81.7%, Cu = 80.3%, Ni = 100.5%, Zn = 89.2% and Co = 101.3%). Relative to their total metal concentrations, nitrate metal dosing (lowest metal concentrations) was the most toxic followed by metal oxides dosing while the annealed dosing method was generally non-toxic. Due to the lack of toxicity of the annealed metals and their higher dosing effort, metal oxides, are the most appropriate of the tested dosing methods, for fixed-ratio metal mixtures studies with soil invertebrates.

Dataset Information

Finding Key Factors for Efficient Water and Methanol Activation at Metals, Oxides, MXenes, and Metal/Oxide Interfaces.

Publications

Finding Key Factors for Efficient Water and Methanol Activation at Metals, Oxides, MXenes, and Metal/Oxide Interfaces.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets