APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Duo Yang,Miaomiao Chen,Jing-He Yang
Phytic acid (PA) is a six-fold dihydrogenphosphate ester of inositol with cost-effective, environmentally friendly, and safe properties. Here, we successfully synthesize the dehydroxyl cobalt phytate (PA-Co-400) using PA as phosphorus sources by a one-pot wet-chemistry strategy to prepare the precursor PA-Co and then heat treatment at 400 °C under an N 2 atmosphere for dehydroxylation. The average diameter, specific surface area, surface element distribution, and catalytic activity of the catalyst are significantly affected by dehydroxylation temperature. The specific surface area increases first and then decreases with the treatment temperature from 200 °C to 600 °C. The SEM results indicate that the average diameter of PA-Co-400 particle is 68.90 nm. The as-prepared samples are used as an anode catalyst for electrocatalytic oxygen evolution reaction (OER). The PA-Co-400 exhibits splendid OER performances with an overpotential of 310.31 mV at j 10 (η 50 = 349.35 mV, η 100 = 367.20 mV), which are even comparable to commercial RuO 2 (η 10 = 310.54 mV, η 50 = 389.80 mV, η 100 = 450.60 mV). Moreover, the PA-Co-400 has a small Tafel slope of 53.27 mV dec −1 , which is lower than commercial RuO 2 (81.71 mV dec −1 ). The ultra-long durability of PA-Co-400 was tested for over 80 h at current densities of 10 mA cm −2 without a significant reduction in 1 M KOH.
研究领域:
材料科学
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电化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2024
·
IF 4.3
Qian Wu,Guo Feng,Feng Jiang,Xiaojun Zhang,Yanqiao Xu,Jianmin Liu,Jian Liang,Xinbin Lao,Zhiqi Guo
This paper reports a facile treatment to enhance the capacity of petal-like MgAl 2 O 4 for Congo red (CR) adsorption. The influence of dehydroxylation treatment on the adsorption performance of petal-like MgAl 2 O 4 is investigated. FT-IR, XPS, TG, XRD and FE-SEM are employed to analyze the differences between samples without and with dehydroxylation. Mechanism on the adsorption capacity improvement of CR by MgAl 2 O 4 after dehydroxylation is investigated systematically. Results show that the adsorption process conforms well to the pseudo-second-order kinetic model and Langmuir isotherm model. The adsorption mechanism study shows that the adsorption of CR on petal-like MgAl 2 O 4 is mainly due to chemisorption including Lewis acid-base interaction and electrostatic attraction. It is observed that the maximum adsorption capacity of petal-like MgAl 2 O 4 after dehydroxylation reaches 3264.54 mg/g, much higher than sample without dehydroxylation (591.72 mg/g). Most Lewis acid sites of petal-like MgAl 2 O 4 (Mg 2+ and Al 3+ ) without dehydroxylation process are occupied by hydroxyl groups. It is not conductive to combine with –NH 2 and –SO 3 2- in CR molecular, resulting in the deterioration of adsorption performance. The activity of Mg 2+ and Al 3+ in MgAl 2 O 4 can be recovered greatly after the removal of hydroxyl groups, and it is favorable to the adsorption between MgAl 2 O 4 and CR.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Minerals
·
2022
·Vol. 12
·期 9
·1097
·
IF 2.818
Dongyue Wang,Yuhang Meng,Aidong Tang,Huaming Yang
Engineered nanoparticle–support interaction is an effective strategy for tuning the structures and performance of engineered nanoparticles. Here, we show that tuning the dehydroxylation of kaolinite nanoclay as the support could induce zinc oxide–kaolinite interactions. We used free energy theory, electron microscopy, and X-ray photoemission spectroscopy to identify interaction strengths between metal oxides and the underlying nanoclay induced by dehydroxylation. Desirable exposure of nanoparticle sites and the geometrical and crystal structure were obtained by tuning the interface interactions between ZnO nanoparticles and nanoclay. The surface free energy of zinc oxide–nanoclay results in different interfacial interactions, and the properties of the surface free energy electron-donating (γ−) and electron-accepting (γ+) parameters have significant effects on the electron acceptor. This could, in turn, promote stronger interactions between zinc oxide and the kaolinite surface, which produce more active (0001) Zn-polar surfaces with promoting zinc oxide nanoparticles growing along the <0001> direction. Reactive oxygen species, leached zinc ions, and electron transfer can modulate the antibacterial activities of the samples as a function of interface free energy. This further demonstrates the interfacial interactions induced by dehydroxylation. This work has new application potential in biomedicine and materials science.Keywords:kaolinite;dehydroxylation;interfacial interactions;ZnO nanoparticles;antibacterial activities
研究领域:
材料科学
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纳米技术
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-10
·
IF 14.7
Lv Jiabao,Cao Ang,Zhong Yunhao,Lin Qingyang,Li Xiaodong,Wu Hao Bin,Yan Jianhua,Wu Angjian
Renewable-driven electrocatalytic nitrate conversion offers a promising alternative to alleviate nitrate pollution and simultaneously harvest green ammonia. However, due to the complex proton-electron transfer processes, the reaction mechanism remains elusive, thereby limiting energy efficiency. Here, we adopt Ni(OH)₂ as a model catalyst to investigate the dynamic evolution of the reaction interface. A proposed OH cycle mechanism involves the formation of a locally OH-enriched microenvironment to promote the hydrogenation process, which is identified through in-situ spectroscopy and isotopic labelling. By further activating the dynamic state through the implementation of surface vacancies via plasma, we achieve a high Faradaic efficiency of almost 100%. The activated interface accelerates the OH cycle by enhancing dehydroxylation, water dissociation, and OH adsorption, thereby promoting nitrate electroreduction and inhibiting hydrogen evolution. We anticipate that rational activation of the dynamic interfacial state can facilitate electrocatalytic interface activity and improve reaction efficiency.
研究领域:
电化学
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催化
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环境科学
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材料科学
✓ 已验证
DOI
高影响因子
Current Research in Food Science
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2023
·
IF 6.3
Shiye Lin,Jesus Simal-Gandara,Hui Cao,Jianbo Xiao
Polyhydroxy flavonols readily degraded during thermal processing. In this study, the UPLC-Q-tof-MS/MS was applied to explore the stability of dietary polyhydroxy flavonols, myricetin, kaempferol, galangin, fisetin, myricitrin, quercitrin and rutin, in boiling water. The decomposition of flavonols was mainly caused by the heterocyclic ring C opening to form simpler aromatic compounds. The degradation products mainly included 1,3,5-benzenetriol, 3,4,5-trihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid and 2,4,6-trihydroxybenzaldehyde, etc. Compared with myricetin with a pyrogallol-type structure on the ring B, the glycoside in myricitrin slightly affects the stability. However, the glycosides in rutin and quercitrin dramatically improved the stability in water. During the boiling process, flavonols underwent a series of chemical reactions, such as hydroxylation, dehydroxylation, deglycosidation, deprotonation, and C-ring cleavage.
研究领域:
食品科学
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分析化学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）