Journal of Materials Chemistry A
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2021
·Vol. 9
·期 30
·16411-16417
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IF 12.732
You Xu,Mingzhen Wang,Kaili Ren,Tianlun Ren,Mengying Liu,Ziqiang Wang,Xiaonian Li,Liang Wang,Hongjing Wang
The development of efficient catalysts for electrocatalytic selective conversion of nitrate pollutants into valuable ammonia is a project of far-reaching importance. This work demonstrated the in situ electroreduction of pre-synthesized CuO nanoplates into defect-rich metallic Cu nanoplates and evaluated their electrocatalytic nitrate-to-ammonia activity. Concentrated atomic defects in the as-converted Cu nanoplates could favor the adsorption, enrichment and confinement of nitrate ions and pivotal reaction intermediates, selectively promoting eight-electron reduction (NH3 formation). Consequently, the resultant defect-rich Cu nanoplates exhibit a significant ammonia production rate of 781.25 μg h−1 mg−1, together with excellent nitrate conversion (93.26%), high ammonia selectivity (81.99%) and good electrocatalytic stability, superior to the defect-free Cu nanoplate counterpart. Isotope labelling experiments demonstrated that the source of ammonia was from nitrate. Both 1H NMR and colorimetric methods were used to quantify the ammonia yield.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2020
·
IF 7.489
Xiaomin Meng,Yirui Ouyang,Huijie Wu,Haowei Huang,Fengqian Wang,Shuo Wang,Mengchao Jiang,Lian Ying Zhang
Tuning the chemical composition and surface structure of electrodes is demonstrated as a feasible and effective strategy to tailor advanced catalysts for energy electrocatalysis. In this work, hierarchical palladium-silver alloy nanosheets (PdAg NS) with the thickness ~7 atoms and rich atomic defects are successfully prepared, using the carbon monoxide (CO) confinement approach. The optimized Pd 7 Ag 3 NS/C exhibits 8.8 times higher catalytic peak current density and much better stability toward ethanol electrooxidation than Pd NS/C catalyst. The catalytic enhancement mechanism could be attributed to the synergetic effects among optimized electronic structure of Pd, novel architecture, and rich atomic defects.
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
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Yanei Xue,Penghui Shao,Mingli Lin,Yixing Yuan,Wenxin Shi,Fuyi Cui
Defect engineering is crucial in the development of semiconductor catalyst activity. However, the influence of defect/vacancy density and states on catalysis remains vague. Thus, the optimized sulfur vacancy (S V ) state is achieved among Fe-ZnS models (ZFS) via a chemical etching strategy for photocatalytic degradation (PD). As the S V concentration (ρS V ) increases, the predominant state of vacancies changes from isolated defects－ a state to a combination of a state and vacancy clusters－ e state, as verified by positron annihilation and X-ray absorption fine structure spectra. However, the two types of defect states activated the intrinsic activity of the crystal via radically different mechanisms and exerted different degrees of influence on PD activity, as revealed by first-principles calculations and quantitative structure-activity relationship. Our results suggest that the S V activity is strongly influenced by its concentration in the ZFS crystal, while the vacancy concentration is not a control parameter for the PD activity, but a defect form. The underlying essence of atomic defects behavior affecting crystal catalytic activity at the atomic level is also revealed in this paper. Uncovering these structural relationships provide a theoretical basis for designing effective catalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Yue Liu,Bing Lan,Yiyi Fan,Dongling Wang,Yifei Cao,Fan Zhang,Xiaobin Xie
Site-selective epitaxial growth of metals onto shaped nanoparticles represents a versatile strategy for tailoring nanostructures to optimize the optical and catalytic properties. In this study, we systematically elucidate the critical factors governing the epitaxial growth of silver and platinum atoms onto gold nanorods (Au NRs), revealing that atomic defects on the Au NR surface dictate the deposition sites of Ag and Pt. By precisely modulating epitaxial growth conditions and density of surface atomic defects, we achieve the synthesis of dumbbell-shaped (DS) and thorny-shell (TS) structured Au-AgPt NRs. Notably, the DS-Au-AgPt0.24 NR catalyst demonstrated exceptional catalytic performance in alcohol fuel cell reactions, driven by their abundant atomic defects and strong strain effects localized at the crown structure. For ethylene glycol electro-oxidation, these DS-Au-AgPt0.24 NRs achieved a mass activity of 23.5 A mgPt–1 and a specific activity of 156.9 mA cm–2, which were 4.1 and 11.2 times higher than that of commercial platinum–carbon (Pt/C) catalysts (5.7 A mgPt–1 and 14.0 mA cm–2), respectively. Our findings not only advance the mechanistic understanding of defect-mediated epitaxial growth in multimetallic systems but also provide a blueprint for designing high-performance catalysts through atomic-scale structural engineering.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Zengbo Ke,Lejing Li,Qiurong Jia,Yangong Yang,Hongwei Cui
Au/Ir bimetals are not easy to obtain because alloy phase diagrams are not available for these material combinations (Ronald et al., 2004). Herein, the Au/Ir nanochains (Au/Ir NCs) are synthesized via one-pot, hydrothermal method . By virtue of jagged surface with abundant atomic defects, the Au/Ir NCs are demonstrated much more active than commercial IrO 2 electrocatalysts for oxygen evolution reaction under alkaline media. The potential of the Au/Ir NCs sustains 1.53 V vs reversible hydrogen electrode (RHE) with no obvious decease under current density at 10 milliamps per square centimeter, while that of IrO 2 increase to 1.65 V vs RHE after stability tests for ca. 32 h. The durability as well as the activity of Au/Ir NCs is attributed to the electronic interaction between Au and Ir, which is confirmed by X-ray photoelectron spectroscopy (XPS).
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Wei Song,Hanqing Zhao,Jianqi Ye,Mengmeng Kang,Siyu Miao,Zhong Li
Ti–O–C channels for ultrafast sodium storage were constructed in N/S-co-doped TiO2–C nanofibers, which deliver a high rate performance of 181.9 mAh g–1 at 5 A g–1 after 3000 cycles. The existence of Ti–O–C bonds at the interface of TiO2–C phases was revealed by synchrotron radiation X-ray absorption spectra. Based on this, first-principles calculations further verified the low energy barrier for Na+ insertion/extraction in the Ti–O–C channels formed by the intimately integrated graphite layer with TiO2 near the surface. In addition, surface defects induced by heteroatoms accelerate the Na+ mass transfer through the pathway from the carbon surface to the Ti–O–C channel.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Qingjie Luan,Xiangdong Xue,Rongjie Li,Lin Gu,Wenjun Dong,Dongxue Zhou,Xing Wang,Baozhen Li,Ge Wang,Changmin Hou
Defect engineering, inducing photo-excited electrons and holes to different surfaces of semiconductor photocatalyst, is an efficient strategy to improve the photocatalytic activity. A rapid heating-up hydrothermal technique is developed to regulate ZnIn 2 S 4 crystal growth, then, ultrathin ZnIn 2 S 4 nanosheets with In defect-rich [InS] 6 interlayer but perfect [InS] 4 and [ZnS] 4 surface layers are successfully prepared (ultra-ZIS-V In ). Interestingly, the In defect, inducing the redistribution of the orbitals near the valence band maximum, separates the oxidation and reduction sites on the opposite sides of the ultra-ZIS-V In nanosheets. Simultaneously, In defects increase the density of states (near the valence band maximum and conduction band minimum) and delocalize the electron around In defects. Accordingly, the photocatalytic hydrogen evolution rate is optimized to 13.4 mmol h −1 g −1 , which is 8.9 times higher than that of defect-free ZnIn 2 S 4 (pristine-ZIS).
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
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2022
·
IF 6.888
Zejian Dong,Na Zhang,Shuangbao Wang,Yuying Liu,Lifeng Zhang,Xing Chen,Langli Luo
Atomic defects are critical to tuning the physical and chemical properties of functional materials such as catalysts, semiconductors, and 2D materials. However, direct structural characterization of atomic defects, especially their formation and annihilation under practical conditions, is challenging yet crucial to understanding the underlying mechanisms driving defect dynamics, which remain mostly elusive. Here, through in situ atomic imaging by an aberration-corrected environmental transmission electron microscope (AC-ETEM), we directly visualize the formation and annihilation mechanism of planar defects in monoclinic WO3 on the atomic scale in real time. We captured the atomistic process of the nucleation dynamics of the dislocation core in the [010] direction, followed by its propagation to form a planar defect. Corroborated by density functional theory-based calculations, we rationalize the formation of dislocation through O extraction from bridge sites followed by an atomic channeling process. These in situ observations shed light on the defect dynamics in oxides and provide atomic insights into forming and manipulating defects in functional materials.
研究领域:
材料科学
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纳米技术
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凝聚态物理
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催化
·
显微学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）