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High-purity Cu nanocrystal synthesis by a dynamic decomposition method.

Jian X, Cao Y, Chen G, Wang C, Tang H, Yin L, Luan C, Liang Y, Jiang J, Wu S, Zeng Q, Wang F, Zhang C - Nanoscale Res Lett (2014)

Bottom Line: The growth was found to be influenced by the factors of reaction temperature, protective gas, and time.High crystalline Cu nanocrystals without floccules were obtained from thermal decomposition of cupric tartrate at 271°C for 8 h under Ar.This general approach paves a way to controllable synthesis of Cu nanocrystals with high purity.

View Article: PubMed Central - PubMed

Affiliation: Clean Energy Materials and Engineering Center, School of Energy Science and Engineering, University of Electronic Science and Technology of China, No. 2006, Xiyuan Avenue, West Hi-Tech Zone, Chengdu, 611731, China, jianxian@uestc.edu.cn.

ABSTRACT
Cu nanocrystals are applied extensively in several fields, particularly in the microelectron, sensor, and catalysis. The catalytic behavior of Cu nanocrystals depends mainly on the structure and particle size. In this work, formation of high-purity Cu nanocrystals is studied using a common chemical vapor deposition precursor of cupric tartrate. This process is investigated through a combined experimental and computational approach. The decomposition kinetics is researched via differential scanning calorimetry and thermogravimetric analysis using Flynn-Wall-Ozawa, Kissinger, and Starink methods. The growth was found to be influenced by the factors of reaction temperature, protective gas, and time. And microstructural and thermal characterizations were performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry. Decomposition of cupric tartrate at different temperatures was simulated by density functional theory calculations under the generalized gradient approximation. High crystalline Cu nanocrystals without floccules were obtained from thermal decomposition of cupric tartrate at 271°C for 8 h under Ar. This general approach paves a way to controllable synthesis of Cu nanocrystals with high purity.

No MeSH data available.


lgβ-1,000 T−1relationship of cupric tartrate at decomposition stages: (a) I and (b) II.
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Fig3: lgβ-1,000 T−1relationship of cupric tartrate at decomposition stages: (a) I and (b) II.

Mentions: where, β, R, T, A, E, and G(α) represent the different heating rates, the ideal gas constant, the thermodynamic temperature, the pre-exponential factor, the activation energy, and the mechanism kinetic equation with integral form, respectively. With different heating rates, the linear relationships can be performed by plotting the logarithm lgβ as a functional of the reciprocal of temperature, 1/T, with the decomposition rate α ranging from 0.1 to 0.9. The activation energy can be calculated from the slope of the linear relationships. We divided the overall decomposition process into two stages, including dehydration (stage I) and decomposition (stage II). The matching lines during stage I have good coefficients of association close to 1, with a standard error of 0.0111 on average (Figure 3a and Table 1). This indicates that stage I can be described by one kinetic equation. On the other hand, stage II cannot be described by one kinetic equation, as the slopes obtained from the linear regression change (Figure 3b and Table 2). This may be due to that generations of tartrate diradical and fragments of C2H2O2, C2H4O2, C2H2O3, C4H4O4, and C4H4O6 break the linear relationships.Figure 3


High-purity Cu nanocrystal synthesis by a dynamic decomposition method.

Jian X, Cao Y, Chen G, Wang C, Tang H, Yin L, Luan C, Liang Y, Jiang J, Wu S, Zeng Q, Wang F, Zhang C - Nanoscale Res Lett (2014)

lgβ-1,000 T−1relationship of cupric tartrate at decomposition stages: (a) I and (b) II.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493849&req=5

Fig3: lgβ-1,000 T−1relationship of cupric tartrate at decomposition stages: (a) I and (b) II.
Mentions: where, β, R, T, A, E, and G(α) represent the different heating rates, the ideal gas constant, the thermodynamic temperature, the pre-exponential factor, the activation energy, and the mechanism kinetic equation with integral form, respectively. With different heating rates, the linear relationships can be performed by plotting the logarithm lgβ as a functional of the reciprocal of temperature, 1/T, with the decomposition rate α ranging from 0.1 to 0.9. The activation energy can be calculated from the slope of the linear relationships. We divided the overall decomposition process into two stages, including dehydration (stage I) and decomposition (stage II). The matching lines during stage I have good coefficients of association close to 1, with a standard error of 0.0111 on average (Figure 3a and Table 1). This indicates that stage I can be described by one kinetic equation. On the other hand, stage II cannot be described by one kinetic equation, as the slopes obtained from the linear regression change (Figure 3b and Table 2). This may be due to that generations of tartrate diradical and fragments of C2H2O2, C2H4O2, C2H2O3, C4H4O4, and C4H4O6 break the linear relationships.Figure 3

Bottom Line: The growth was found to be influenced by the factors of reaction temperature, protective gas, and time.High crystalline Cu nanocrystals without floccules were obtained from thermal decomposition of cupric tartrate at 271°C for 8 h under Ar.This general approach paves a way to controllable synthesis of Cu nanocrystals with high purity.

View Article: PubMed Central - PubMed

Affiliation: Clean Energy Materials and Engineering Center, School of Energy Science and Engineering, University of Electronic Science and Technology of China, No. 2006, Xiyuan Avenue, West Hi-Tech Zone, Chengdu, 611731, China, jianxian@uestc.edu.cn.

ABSTRACT
Cu nanocrystals are applied extensively in several fields, particularly in the microelectron, sensor, and catalysis. The catalytic behavior of Cu nanocrystals depends mainly on the structure and particle size. In this work, formation of high-purity Cu nanocrystals is studied using a common chemical vapor deposition precursor of cupric tartrate. This process is investigated through a combined experimental and computational approach. The decomposition kinetics is researched via differential scanning calorimetry and thermogravimetric analysis using Flynn-Wall-Ozawa, Kissinger, and Starink methods. The growth was found to be influenced by the factors of reaction temperature, protective gas, and time. And microstructural and thermal characterizations were performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry. Decomposition of cupric tartrate at different temperatures was simulated by density functional theory calculations under the generalized gradient approximation. High crystalline Cu nanocrystals without floccules were obtained from thermal decomposition of cupric tartrate at 271°C for 8 h under Ar. This general approach paves a way to controllable synthesis of Cu nanocrystals with high purity.

No MeSH data available.