Reaction Kinetics Mechanisms and Catalysis
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2021
·Vol. 132
·期 1
·301-315
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IF 2.081
Hu Yi-Ming,Zheng Wan-Bin,Jia Ai-Ping,Luo Meng-Fei,Tang Cen,Lu Ji-Qing
A series of Ir/BN catalysts with same Ir contents (2 wt%) were calcined at different temperatures and tested for gas phase selective hydrogenation of crotonaldehyde. It was found that the thermal treatment exerted significant impacts on the structural and electronic properties of the 2Ir/BN catalysts. The catalyst calcined at 500 °C (2Ir/BN-5) showed the best performance, with a steady state of conversion of ca. 21% and a crotyl alcohol selectivity of ca. 83% at reaction temperature of 80 °C. Kinetic analysis indicated that the enhanced activity on the 2Ir/BN-5 catalyst was related to its higher surface coverage of crotonaldehyde because of the presence of small Ir particles (with a mean diameter of 3.4 nm) compared to those in the catalyst calcined at 600 °C (2Ir/BN-6, with a mean diameter of 4.4 nm). Also, the surface of the Ir species in the 2Ir/BN-5 catalyst are more electron-enriched compared to that in the 2Ir/BN-6, which suppressed the adsorption of C=C bond and thus improves the selectivity to CROL.
研究领域:
催化
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化学工程
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物理化学
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DOI
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Liangchen Yue,Hao Guo,Junjie Hua,Miao Yu,Keliang Liu,Xian Yang,Jianzhong Liu,Jun Cheng
To develop a low-cost acidic water electrolysis catalyst with high efficiency and stability and low Ir content, a catalyst with highly dispersed Ir/Fe complex sites (∼ 5 wt% Ir) was synthesized by a simple carbonization and oxidation process. N-defective g-C 3 N 4 (N CN) was introduced to enhance the support effect between metal nanoparticles and CN bases and the intrinsic catalytic activity for the oxygen evolution reaction (OER). N CN provided more active sites and adjusted the electronic structure of CN. Compared with the original single Ir catalyst, the electrons of the Ir-Fe metal catalyst were transferred from the base to the metal, which maintained the high OER performance and stability of the catalyst. Density functional theory calculations demonstrated that the Gibbs free energy of Ir/Fe@N CN was greatly reduced during O*→OOH* as the rate-determining step. The overpotential of the Ir/Fe@N CN catalyst was 242 mV at 10 mA/cm 2 , and its mass activity (612.6 A/g) was much higher than that of IrO 2 (88.6 A/g), showing excellent OER performance. This study provides a new strategy for the design and optimization of highly efficient and low-cost acidic Ir/transition metal OER catalysts.
研究领域:
催化
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材料科学
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电化学
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能源材料
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2025
·
IF 8.2
Qi Wang,Kaini Zhang,Zhengqi Zhang,Xin Chen,Hao Deng,Weibo Hua,Jinjia Wei,Shaohua Shen,Jie Chen
Reducing iridium (Ir) loading while maintaining efficiency and stability is crucial for the acidic oxygen evolution reaction (OER). In this study, we develop a synthetic method of sequential electrochemical deposition and high-temperature thermal shock to produce an IrOx/Ir-WO3 electrocatalyst with ∼1.75 nm IrOx nanoparticles anchoring on Ir-doped WO3 nanosheets. The IrOx/Ir-WO3 electrocatalyst with a low Ir loading of 0.035 mg cm–2 demonstrates a low overpotential of 239 mV to achieve a current density of 10 mA cm–2 and a mass activity of 6.6 × 104 A gIr–1 @1.75 V vs RHE in 0.5 M H2SO4. IrOx/Ir-WO3 on carbon paper as the anode and Pt/C as the cathode work stably for 40 h at 30 mA cm–2 in a proton exchange membrane water electrolyzer. It is found that the cooperation of lattice-doped Ir and surface-anchored IrOx enhances the activity and stability of IrOx/Ir-WO3 for acidic OER. Specifically, the doped Ir reduces the electron density of the anchored IrOx, thus optimizing the adsorption energy of oxygen-containing intermediates and the kinetic barrier of H2O dissociation, leading to an enhanced activity of IrOx/Ir-WO3. Also, the Ir-WO3 support provides electrons to retard the overoxidation and dissolution of Ir atoms from the anchored IrOx during acidic OER.
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2021
·
IF 3.882
Hongbo Yu,Jihao Zhao,Chunzheng Wu,Bo Yan,Shuangliang Zhao,Hongfeng Yin,Shenghu Zhou
Decoration of noble metals with transition-metal oxides has been intensively studied for heterogeneous catalysis. However, controllable syntheses of metal–metal oxide heterostructures are difficult, and elucidation of such interfaces is still challenging. In this work, supported IrCo alloy nanoparticles are transformed into supported Ir–CoOx close-contact nanostructures by in situ calcination and following selective reduction. Relative to Ir/Al2O3, Ir–CoOx/Al2O3 shows greatly enhanced activities for the hydrogenation of furfural derivatives to the corresponding furfuryl alcohol derivatives with more than 99% selectivity and demonstrates significantly improved activities and selectivity for hydrogenations of α,β-unsaturated aldehydes to α,β-unsaturated alcohols. The modification of Ir surfaces with CoOx prevents Ir nanoparticles from growing, achieving high thermal and catalytic stabilities. Theoretic calculation suggests that the better catalytic performance of Ir–CoOx/Al2O3 is ascribed to the Ir–CoOx interaction, which promotes the absorption of furfural as well as desorption of furfuryl alcohol, resulting in enhanced catalytic activities.
研究领域:
催化化学
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材料科学
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能源化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2016
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IF 7.145
Yangjun Chen,Zuhong Li,Haibo Wang,Yin Wang,Haijie Han,Qiao Jin,Jian Ji
IR-780 iodide, a near-infrared (near-IR) fluorescent dye, can be utilized as an effective theranostic agent for both imaging and photothermal therapy. However, its lipophilicity limits its further biomedical applications. Herein, we synthesized a phospholipid mimicking amphiphilic homopolymer poly(12-(methacryloyloxy)dodecyl phosphorylcholine) (PMDPC) via reversible addition–fragmentation chain transfer (RAFT) polymerization. The amphiphilic homopolymer PMDPC can be self-assembled into micelles and used for the encapsulation of IR-780. The IR-780 loaded micelles (PMDPC-IR-780) exhibited low cytotoxicity in the dark, whereas remarkable photothermal cytotoxicity to pancreatic cancer cells (BxPC-3) was observed upon near-IR laser irradiation. We further investigated in vivo biodistribution of PMDPC-IR-780 micelles. Higher accumulation of PMDPC-IR-780 than that of free IR-780 in tumor tissue was verified, which might be ascribed to the enhanced permeability and retention (EPR) effect and long circulation time benefiting from the zwitterionic phosphorylcholine surface. Therefore, the IR-780 loaded phospholipid mimicking homopolymeric micelles could have great potential for cancer theranostics.
研究领域:
生物医学工程
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肿瘤学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Inorganics
·
2022
·Vol. 10
·期 3
·29
·
IF 3.149
Van Thi Thanh Ho,Dung Hung Chau,Khang Quang Bui,Ngan Thi Thanh Nguyen,Thi Kim Ngan Tran,Long Giang Bach,Son Nguyen Truong
TiO2-based photocatalysts still have some limitations such as large bandgap and low surface area, leading to low efficiency in the photocatalytic degradation of VOCs and limiting it to use in sunlight. Here we report that the nanostructured Ir-doped TiO2as an efficient photocatalyst generates an excellent risk-reduction material of gaseous toluene. We have succeeded in developing a nanostructured Ir-dopedTiO2and initially found that excellent efficient photocatalytic VOC decomposition can be achieved in our materials The nanostructured Ir-dopedTiO2was synthesized by a one pot, low temperature hydrothermal process with different ratios of Ir doped into theTiO2. It exhibited a high surface area, uniformly spherical morphology of 10–15 nm. Its activity for the photocatalytic degradation of gaseous toluene exhibited up to 97.5% under UV light. This enhancement could be explained by iridium doping which created a high concentration oxygen vacancy and changed the recombination rate of the photogenerated charge carriers. More generally, our study indicates a strategic way to develop the novel nanostructured material for numerous applications.Keywords:photocatalysts;Ir-doped TiO2;VOCs;toluene
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2015
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IF 3.391
Zhengzong Wu,Enbo Xu,Jie Long,Xiaowei Pan,Xueming Xu,Zhengyu Jin,Aiquan Jiao
The application of attenuated total reflectance infrared spectroscopy (ATR-IR), Raman spectroscopy (RS) and combination of ATR-IR and RS for measurements of total antioxidant capacity (TAC) and total phenolic content (TPC) of Chinese rice wine (CRW) were investigated in this study. Synergy interval partial least-squares (SiPLS), support vector machine (SVM) and principal component analysis (PCA) were applied to process the merged data from two individual instruments. It was observed that the performances of models based on the RS spectra were better than those based on the ATR-IR spectra. In addition, SVM models based on the efficient information extracted from ATR-IR and RS spectra were superior to PLS models based on the same information and PLS models based on ATR-IR or RS spectra. The overall results demonstrated that integrating ATR-IR and RS was possible and could improve the prediction accuracy of TAC and TPC in CRWs.
研究领域:
食品科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
ACS Omega
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2020
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IF 2.87
Fengqing Xiong,Danni Chen,Chenglong Ma,Limei Cao,Ji Yang
Electrochemical oxidation has been considered as an efficient method to degrade pharmaceuticals and personal care products. Maintaining low power consumption while increasing the number of oxidation intermediates is deserving of exploring. Herein, Ti/SnO2–Sb/Zr0.3Ir0.7O2 was prepared by Zr doped into IrO2 and used for Sulfamethoxazole (SMX) degradation. The addition of Zr significantly increased the electrochemically active area and facilitated the catalyst to degrade SMX dramatically at a lower overpotential. The extremely outstanding lifetime of catalysts can reach 800 h during the accelerated life test, which showed excellent stability and developmental prospects. The overpotential at 10 mA·cm–2 is about 329 mV, indicating that this electrode has a high oxygen evolution reaction activity. Furthermore, the electrical efficiency per log order for the electrode is only 8.50 kW h m–3 at 4 V. Our research provides new anode electrochemical catalysts for the degradation of organic pollutants.
研究领域:
环境科学
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材料科学
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电化学工程
✓ 已验证
DOI
高影响因子
PHYTOCHEMICAL ANALYSIS
·
2024
·
IF 3
Kaidi Lv,Chunling Yin,Fang Li,Wenbo Chen,Liuchuang Zhao,Zhimin Liu,Leqian Hu
Introduction Quality evaluation of Huang-qin is significant to ensure its clinical efficacy. Objective This study aims to establish an accurate, rapid and comprehensive Huang-qin quality evaluation method to overcome the time-consuming and laborious shortcomings of traditional herbal medicine quality assessment methods. Methods The contents of baicalin, baicalein and scutellarin in Huang-qin from five different origins were analyzed by FT-IR and NIR spectra combined with multivariate data technology. The quality of Huang-qin from different origins was evaluated by TOPSIS and consistency analysis based on the content of three active ingredients. The correlation between ecological factors and the accumulation of active ingredients was explored. Results Satisfactory prediction results of PLS models were obtained. Relatively, the model based on FT-IR combined with the PLS regression method has higher R 2 and smaller RMSE than the NIR combined with the PLS method. TOPSIS and consistency analysis results showed that the quality of Huang-qin from different geographical origins was significantly different. The results showed that the quality of Huang-qin produced in Shanxi Province was the best among the five origins studied. The results also found that the quality of Huang-qin in different growing areas of the same origin was not completely consistent. The correlation study showed that altitude, sunshine duration and rainfall were the main factors that caused the quality difference of medicinal materials in different geographical origins. Conclusion This study provides a reference for the rapid quantitative analysis of the active components of herbal medicine and the quality evaluation of them.
研究领域:
中药学
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分析化学
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药理学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Guoqiang Li,Kai Li,Long Yang,Jinfa Chang,Rongpeng Ma,Zhijian Wu,Junjie Ge,Changpeng Liu,Wei Xing
Reducing the noble-metal loading without sacrificing the catalytic performance of the oxygen evolution reaction (OER) catalysts is paramount yet highly challenging. Herein, IrO2@Ir/TiN electrocatalysts employing TiN as the support have been developed and shown high efficiency toward OER. TiN is found not only to disperse the IrO2@Ir nanoparticles effectively but also to exert the electronic modulation of Ir by downshifting its d-band center of 0.21 eV compared to pure IrO2. Excitingly, TiN remarkably enhances the catalytic performance of Ir, where the overpotential to achieve the current density of 10 mA cm–2 is only 265 mV for the IrO2@Ir/TiN (60 wt %) catalyst. As a result, 71.7 wt % of the Ir metal can be saved to compare with the commercial Ir-black counterpart. Moreover, TiN can inhibit the aggregation and oxidative dissolution of Ir species, thereby enhancing the operational stability. The combined advantages of TiN open a new solution to reduce the anodic catalyst cost through boosting the catalytic activity and stability.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Jiayi Li,Shiwei Wang,Zhihao Yu,Haojian Zhang,Lin Zhu,Chunzheng Wu,Hongbo Yu
The selective hydrogenation of halogenated nitroarenes into halogenated anilines poses a significant challenge due to the common issue of dehalogenation, which often results in low selectivity. In this research, we developed SiO2-supported Ir-MoOx nanostructures through the in situ transformation of IrMo/SiO2. The Ir-MoOx/SiO2 catalyst we produced, with an optimal Ir/Mo molar ratio of 1:1, achieved a 95.1% conversion rate for p-chloronitrobenzene (p-CNB) and a 97.4% selectivity for p-chloroaniline (p-CAN), significantly outperforming the standalone Ir/SiO2 catalyst. We explored how the MoOx promoter affects the electronic properties of Ir particles and examined the impact of Ir-MoOx interfaces on catalytic hydrogenation. This was done using advanced techniques, such as H2 temperature-programmed reduction (H2-TPR), H2 temperature-programmed desorption (H2-TPD), O2 temperature-programmed oxidation (O2-TPO), diffuse reflectance infrared Fourier transform spectroscopy, and kinetic analysis. The study revealed that the Ir-MoOx interface plays a crucial role in facilitating H2 dissociation and enhancing the adsorption of the reactants. Our Ir-MoOx/SiO2 catalyst showed excellent versatility across a wide range of substrates and maintained strong catalytic stability. This approach has the potential to be applied to other noble-metal-oxide systems for the efficient hydrogenation of halogenated nitroarenes.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
Tungsten
·
2024
·
IF 5.6
Weng Yu-Jing,Ding Zhao-Ying,Li Ying-Chao,Wu Yuan-Feng,Xu Yuan-Yang,Chen Rui,Zhao Xiao-Lei,Wang Hai-Yong,Zhang Da-Lei,Zhang Yu-Long
Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications, including biological pathways and chemical processes. The chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods, offering a sustainable and carbon–neutral alternative to existing petrochemical and biological processes. Herein, Ir/WO x catalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic acid. The catalyst achieved a high ethanol yield of 66.5% under optimal reaction conditions, approaching the theoretical yield limit of traditional ethanol fermentation. Characterization results revealed the presence of oxygen defects, Bronsted/Lewis acidity, and Ir nanoclusters on the catalyst surface, working synergistically to facilitate the cascade catalysis of cellulose hydrolysis, sugar retro-aldol condensation reaction, and C2 intermediate hydrodeoxygenation to ethanol. In situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol production. By manipulating subtle structural features, this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.
研究领域:
催化化学
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可再生能源
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）