Chem
·
2023
·
IF 23.5
Yibo Wang,Rongpeng Ma,Zhaoping Shi,Hongxiang Wu,Shuai Hou,Ying Wang,Changpeng Liu,Junjie Ge,Wei Xing
The acidic oxygen evolution reaction (OER) faces great difficulty in concurrently addressing the site-specific activity and stability of the up-to-date choice Ir-based catalysts. Herein, we adopted a new inverse doping strategy to devise a Ti atomic doping into the surficial IrO x /Ir matrix to investigate the boosting effect of Ir-O-Ti motifs toward OER. Notably, only 1.92 wt % Ti introduction leads to 3.6 times and an order of magnitude improvement in intrinsic activity and stability, respectively, ascribed to the creation of abundant Ir-O-Ti motifs. While the Ti sites donate electrons to weaken the Ir-O interaction and thereby ignite Ir sites activity via adsorbate evolution mechanism (AEM), the restricted O–O bond formation in the lattice oxygen mechanism (LOM) and the widened stable region of Ir species help enhance the stability. This work provides a novel insight into the reactivity of atomic-level interface motifs in heterogeneous components, which inspires further design of advanced catalysts.
研究领域:
材料科学
·
电催化
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2021
·
IF 5.706
Cen Tang,Fangru Zhou,Yang Wen,Yumeng Xu,Aiping Jia,Mengfei Luo,Jiqing Lu
A series of MoO x -promoted Ir/BN catalysts were tested for liquid phase selective hydrogenation of crotonaldehyde. The MoO x -promotion could significantly improve the reactivity up to 5-fold. Such improvement was mainly due to the formation of Ir-MoO x interfacial sites in the promoted catalyst, which accelerated the adsorption and activation of crotonaldehyde molecule as evidenced by a much lower activation energy (18.9 kJ mol −1 on the 0.3Mo-3Ir/BN versus 38.4 kJ mol −1 on the 3Ir/BN). The kinetic results revealed negative reaction order of crotonaldehyde (up to -1.1) and high reaction order of H 2 (up to 2.2), indicating the high coverage of crotonaldehyde on the catalyst surface suppressed the adsorption of H 2 due to its low solubility in the liquid phase. Therefore, the adsorption and activation of H 2 on the catalyst might be the rate determining step. However, the preferred adsorption of crotonaldehyde on the Ir-MoO x interface alleviated the suppression of H 2 adsorption, which was another reason for the higher activity.
研究领域:
催化化学
·
材料科学
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2023
·
IF 2.8
Zhen-Xing Yang,Fang-Fang Ye,Ding Pan,Guang-Xu Yan,Shao-Hui Guo
Acrylonitrile wastewater was an organic wastewater with strong toxicity and poor biodegradability. Therefore, electro-catalytic technology became a promising acrylonitrile wastewater treatment technology because of no secondary pollution, wide application range and low water quality requirements. The optimal Mn-Sn modified Ru-Ir electrode material was synthesized by thermal method and applied in electro-catalytic treatment of acrylonitrile wastewater. The electrode materials were characterized by SEM, TEM, XRD, XPS and electrochemical characterization. SEM, TEM, XRD and XPS indicated that Mn and Sn were capable of incorporating and replacing the part of Ru or Ir and could alter the microstructure of Ru-Ir and the types of Mn and Sn oxides, raising the oxygen evolution potential (OEP) and voltampere charge. When the molar ratio of Mn-Sn was 1:1, OEP, voltampere charge and exchange current density could reach 1.303 V, 1.51 C/cm2 and 6.29×10-4 A/cm2, respectively. The co-doping of Mn-Sn had significant influence on the electrocatalytic performance of Ru-Ir electrode materials. The optimum synthesis conditions of Mn-Sn modified Ru-Ir electrode were as follows: the molar ratio of Mn-Sn was 1:1, calcination time was 4.0 hours, calcination temperature was 450℃, and solvent was water. Under certain conditions, the removal rate of acrylonitrile with Mn-Sn modified Ru-Ir electrode was 100%. Mn-Sn modified Ru-Ir electrode had high oxygen evolution potential and good removal effect of acrylonitrile, which was higher than that of ruthenium iridium electrode and RuO2 electrode.
研究领域:
环境科学
·
材料科学
·
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
Bin Chen,Jun Hu,Zhihao Yu,Lin Zhu,Chunzheng Wu,Hongbo Yu
Improving catalytic hydrogenation by modifying noble metal catalysts with metal-oxide promoters is promising, but precisely controlling the metal–promoter interface to optimize performance is still challenging. In this study, we created Ir-SnO2/SiO2 nanocatalysts with different Ir/Sn ratios using IrSn alloy precursors through careful calcination and reduction treatments. The SnO2-promoted catalysts showed much better conversion and selectivity than the original Ir/SiO2 catalyst toward the hydrogenation of acetophenone to phenylethanol. The Ir-SnO2/SiO2 catalyst with an Ir/Sn molar ratio of 5/1 (i.e., sample Ir5-(SnO2)1/SiO2) performed the best, achieving a 94% conversion rate and 99% selectivity. Our study found that SnO2 promoters could reduce the surface electron density of the Ir nanoparticles (NPs), enhancing the adsorption of reactants; meanwhile, the new Ir-SnO2 interface is more active for the dissociation of hydrogen compared to Ir alone. The optimal Ir5-(SnO2)1/SiO2 catalyst has demonstrated versatility by effectively catalyzing the hydrogenation of C═O bonds in a wide range of compounds, showing significant potential for various industrial applications in fine chemical synthesis and energy conversion.
研究领域:
催化化学
·
材料科学
·
工业化学
✓ 已验证
产品关联
DOI
高影响因子
DRUG DEVELOPMENT AND INDUSTRIAL PHARMACY
·
2020
·
IF 2.365
Jie Liu,Liang Fang,Chao Liu
Objective: This study was to clarify the molecular mechanism of viscoelastic performance variations of pressure-sensitive adhesive (PSA) with the addition of drugs by FT-IR spectroscopy and molecular modeling.Significance: Viscoelastic performance of PSA was frequently changed by the addition of drugs in drug-in-adhesive (DIA) patches. It may cause decrease of the physical stability and drug bio-adhesion issues for the development of DIA patch. But, the molecular details of drug–PSA interaction are not clarified.Methods: Model drugs including propranolol (PRO), oxybutynin (OXY), and escitalopram were added into patch with hydroxyl PSA (10%, w/w). Rheological study and thermal analysis were used to characterize the viscoelastic performance and free volume of PSA, respectively. 1H NMR was used to determine the quantity of hydroxyl group in the PSA. FT-IR study and molecular modeling were conducted to describe the types and interaction sites between drug and PSA molecule.Results: The results demonstrated that PRO interacted with –OH and –COOR groups of PSA, which interrupted the interaction between the PSA molecules, resulting in a plasticizing phenomenon of PSA. Escitalopram mainly interacted with –OH of PSA and decreased the rigidity of the drug-loaded PSA only in the high-frequency region. No obvious interaction was found between OXY and PSA, and the viscoelastic performance of PSA did not change significantly.Conclusion: The present study described the molecular mechanism of viscoelastic performance variation, especially the plasticizing effect. These results were essential for the design and development of transdermal patches from the viewpoint of viscoelastic performance.
研究领域:
药剂学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 18
·9091-9102
·
IF 6.97
Dahui Fang,Xuejun Tang,Limeng Yang,Dongyan Xu,Hongjie Zhang,Shucheng Sun,Zhigang Shao,Baolian Yi
Pt-Decorated Ir black (Pt@Ir) nanoparticles with two varying Pt mass fractions (Pt4@Ir96 and Pt16@Ir84) were generated by a facile method in water with the aid of Ir black. The Pt@Ir nanoparticles were investigated as a bifunctional oxygen catalysts for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in acidic medium. Benefiting from the good dispersion of ultrafine Pt nanodots on the Ir black surface and the synergistic effect between the Pt and underlying Ir atoms, Pt@Ir nanoparticles have exhibited outstanding ORR activity and comparable OER performance in comparison with commercial Ir black. In particular, Pt16@Ir84 shows an ORR mass activity of 2.6 times that of commercial Pt black and exhibits much better bifunctional performances than a mixture of Pt black and Ir black with a Ir/Pt mass ratio of 50/50 (Pt50Ir50). Our work highlights the effectiveness of decorating Ir black with Pt nanodots to fabricate bifunctional oxygen catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Functional Materials Letters
·
2023
·
IF 1.3
Yue Wang,Shuang Chen,Yifan Huang,Jian Gao,Ziqi Deng,Yifan Zhang,Pengyang Deng
Developing photosensitizers with high durability is desirable to boost the practical application of photocatalytic hydrogen evolution. Herein, referring to the successful strategy in the field of light-emitting electrochemical cells, the reported Ir(III) complex with intramolecular π – π interaction, Ir2 , is used as a photosensitizer to explore its durability. Photocatalytic hydrogen evolution experiment exhibits that the durability of Ir2 is significantly improved with the duration of 39 h, which is three times longer than that of the classical Ir(III) complex Ir1 ( ca . 13 h) under the same condition. As revealed by theoretical calculation, the incorporation of intramolecular π – π interaction inhibits the rupture of metal–ligand bond in the excited state, thereby reducing the possibility of complex degradation. This is a novel approach to achieve a durable Ir(III) photosensitizer, which stimulates new molecular engineering endeavors. The finding proves the applicability of molecular design strategy in the field of light-emitting electrochemical cells to the photocatalytic hydrogen evolution system, thus boosting the cross integration of different disciplines.
研究领域:
化学
·
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Liang Wang,Jinqiang Zhang,Jun Huang,Qun Cui,Yuezhao Zhu,Haijun Chen
Supported Ni and Ir nanocatalysts have been used in CO2 dry reforming of methane (DRM); however, their fast deactivation limited further applications. In this research, we introduced NiO nanoparticles (NPs) on the SiO2 surface ahead of the addition of the Ir source for the bimetallic Ir–Ni/SiO2 catalyst. The homogeneous NiO NPs provide finite spaces to prohibit the agglomeration of Ir NPs under H2 reduction. The Ir–Ni/SiO2 catalyst was obtained with ultrasmall bimetallic NPs (1.4 nm) uniformly distributed on the SiO2 surface. Owing to the synergistic effects within the bimetal, the catalytic performance on the fabricated bimetallic catalyst into the DRM reaction is significantly enhanced, with 1.2 times higher than the sum of the Ir and Ni monometallic catalysts. Besides, the side reaction of the reverse water–gas shift reaction is effectively suppressed, and the stability is also improved. This facile strategy provides another approach to fabricate ultrasmall and homogeneous bimetallic catalysts for efficient storage and conversion of fossil fuels.
研究领域:
化学工程
·
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
·
IF 20.2
Wenqing Xu,Yixi Wang,Hong He,Jun Yang,Yang Yang,Jinzhu Ma,Chaoqun Li,Tingyu Zhu
High–performance catalysts are extremely required for controlling NH 3 emission via selective catalytic oxidation (SCO), and the anchoring structural feature of active sites is a key prerequisite for developing them. This study confirms the importance of hydroxyl groups on vacancy–deficient reducible oxides as active groups. On the one hand, spontaneous atomic dispersion of active metal Ir is promoted by the abundant terminal hydroxyl groups. On the other hand, Ir cations anchor on the TiO 2 surface through exchange with H + in Ti–OH groups, and thus occupy the Brönsted acid sites. The adsorption strength of NH 3 is another key factor affecting the reaction rate–determining step, namely NH 3 dehydrogenation , which occurs at a faster rate in the coordinated L–NH 3 rather than the ionic B–NH 4 + . Meanwhile, the coordinated L–NH 3 significantly avoids the competitive adsorption of water vapor in the NH 3 –SCO reaction by reducing the number of hydrogen bonding. The TOF of preferred 0.8Ir/TiO 2 sample is significantly higher than 0.2Ir/TiO 2 sample, although Ir is almost always atomic dispersed. Finally, NH 3 conversion is 85% in a wet circumstance (5% H 2 O) at 240 °C (GHSV = 85 000 h –1 ), with a N 2 selectivity of up to 65% on 0.8Ir/TiO 2 sample.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2017
·
IF 7.78
Jiajun Liu,Youshen Wu,Yao Yu,Ke Li,Yuanyuan Ji,Daocheng Wu
A novel protocol is developed to prepare quantum dot (QD)/Ir(III) complex glycerol monoolein (GMO) cubic-phase nanoparticles (Qd/Ir GMCPNPs) as hypoxia nanoprobes, in which hypoxia probe Tris [1-phenylisoquinoline-C2, N] Iridium(III) [Ir(piq) 3 ] and the reference QDs are separately loaded at hydrophilic and hydrophobic channels to avoid interference. Qd/Ir GMCPNPs were nearly spherical in shape, with an average size of 20–30 nm. Their phosphorescence spectra showed that nanoprobes have a wide excited wave length range of 360–500 nm, which is suitable for different types of measurement instruments . When the oxygen content decreased from 21% to 1%, the luminescent intensity ratio of Qd/Ir GMCPNPs in the solution and cells increased 4-fold and 2.8-fold, respectively, with an acceptable linear relationship. Particularly, extensive preliminary quantitative ratiometric oxygen sensing and long tumor imaging monitoring can be achieved with these nanoprobes.
研究领域:
生物医学工程
·
纳米医学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CONTROLLED RELEASE
·
2016
·
IF 7.441
Wenting Song,Peng Quan,Shanshan Li,Chao Liu,Siji Lv,Yongshan Zhao,Liang Fang
In patches, a drug must release from patches prior to its percutaneous absorption. Chemical enhancers have been used for several decades, but their roles in drug release from patches are poorly understood. In this work, the roles of chemical enhancers in bisoprolol tartrate (BSP-T) release from patches were probed in vitro and in vivo. More importantly, an innovative mechanism insight of chemical enhancers in drug release process was provided at molecular level. FT-IR spectroscopy and molecular modeling were employed to investigate the influence of chemical enhancers on drug-adhesive interaction. The results showed chemical enhancers like Span 80 , which had a strong ability forming hydrogen bonds , could decrease drug-adhesive interaction leading to the release of drug from adhesive of patches. Thermal analysis was conducted to research the influence of chemical enhancers on the thermodynamic properties of patch system. It showed that chemical enhancers promoted the formation of free volume of adhesive, which facilitated drug release process. By contrast, the influence on the thermodynamic properties of BSP-T was less effective in influencing BSP-T release process. In conclusion, chemical enhancers played an important role in facilitating BSP-T release from the adhesive DURO-TAK® 87-2287 of patches by decreasing drug-adhesive interaction and promoting the formation of free volume of adhesive. This work may be an important step in understanding the important roles of chemical enhancers in drug release process.
研究领域:
药剂学
·
生物医学工程
·
药物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Kai Peng,Weiqi Zhang,Narayanamoorthy Bhuvanendran,Qiang Ma,Qian Xu,Lei Xing,Lindiwe Khotseng,Huaneng Su
Pt-based alloy nanomaterials with nanodendrites (NDs) structures are efficient electrocatalysts for methanol oxidation reaction (MOR), however their durability is greatly limited by the issue of transition metals dissolution. In this work, a facile trace Ir-doping strategy was proposed to fabricate Ir-PtZn and Ir-PtCu alloy NDs catalysts in aqueous medium, which significantly improved the electrocatalytic activity and durability for MOR. The as-prepared Ir-PtZn/Cu NDs catalysts showed distinct dendrites structures with the averaged diameter of 4.1 nm, and trace Ir doping subsequently improved the utilization of Pt atoms and promoted the oxidation efficiency of methanol. The electrochemical characterizations further demonstrated that the obtained Ir-PtZn/Cu NDs possessed enhanced mass activities of nearly 1.23 and 1.28-fold higher than those of undoped PtZn and PtCu, and approximately 2.35 and 2.67-fold higher than that of Pt/C in acid medium. More excitingly, after long-term durability test, the proposed Ir-PtZn and Ir-PtCu NDs still retained about 88.9% and 91.6% of its initial mass activities, which further highlights the key role of Ir-doping in determining catalyst performance. This work suggests that trace Ir-doping engineering could be a promising way to develop advanced electrocatalysts toward MOR for direct methanol fuel cell (DMFC) applications.
研究领域:
材料科学
·
电化学
·
燃料电池
✓ 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）