Synthesis and characterization of Ce-doped CuO nanostructures and their photocatalytic activities

doi:10.1016/j.matlet.2016.01.020

Materials Letters

Volume 167, 15 March 2016, Pages 266-269

https://doi.org/10.1016/j.matlet.2016.01.020 Get rights and content

Highlights

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Ce-doped CuO nanoleaves were synthesized by co-precipitation method.
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Their photocatalytic activities were evaluated through methylene blue degradation.
•
3 mol% Ce-doped CuO exhibited the highest photocatalytic performance.

Abstract

Multiple nanoplate-like CuO and Ce-doped CuO nanoleaves were synthesized by a simple co-precipitation of Cu(NO₃)₂∙6H₂O and Ce(NO₃)₃∙6H₂O in alkaline solutions. In this research, the as-synthesized samples were monoclinic CuO with high crystalline degree. Undoped CuO was composed of multiple nanoplate clusters, which were broken and transformed into nanoleaves for Ce-doped CuO samples. The undoped CuO and 3 mol% Ce-doped CuO were applied for photodegradation of methylene blue under UV light. The last showed the best photocatalytic performance to degrade the methylene blue dye.

Introduction

Recently, metal oxide nanostructures such as ZnO, TiO₂, WO₃ and MoO₃ have great attention to degrade organic dyes contaminated in water [1], [2], [3], [4]. CuO is a p-type semiconductor with 1.2 eV band gap [5], [6]. CuO has become known as a multifunctional material for both scientific research and industries because it can be utilized in a wide range of applications: lithium-ion batteries, supercapacitors, sensors, photodetectors, solar cells, heterogeneous catalyst, magnetic storage media and field emissions [5], [6], [7], [8].

In this report, multiple CuO nanoplates and Ce-doped CuO nanoleaves were successfully synthesized by a simple and low-cost chemical method. Then, the photocatalysis for waste water treatment was studied by evaluating the degradation of methylene blue (MB) under UV radiation.

Section snippets

Experiment

Typically, 0.03 mol Cu(NO₃)₂∙6H₂O and 0–3 mol% Ce(NO₃)₃∙6H₂O were dissolved in 20 ml distilled water under stirring at room temperature. Subsequently, 3 M NaOH was slowly dropped into the solutions until their pH was 13 and some suspensions formed. The as-formed suspensions were aged in the dark for 2 weeks to form precipitates. Finally, the precipitates were washed three times with double distilled water and ethanol to remove unreacted reagents and dried in an oven at 60 °C for 24 h.

To evaluate

Results and discussion

Fig. 1 shows XRD patterns of 0–3 mol% Ce-doped CuO samples. The pattern of CuO was specified as monoclinic CuO (JCPDS file no. 05-0661) [9] and shows a well-defined diffraction peaks at 2θ of 32.5°, 35.6°, 38.7°, 48.8°, 53.4°, 58.3°, 61.6°, 66.2°, 68.1°, 72.4° and 75.1°, corresponding to the (110), (002), (−111), (−112), (112), (020), (202), (022), (−311), (220) and (004) planes of monoclinic CuO. Comparing to the Ce-doped CuO patterns, the (002) and (−111) peaks were slightly shifted towards

Conclusions

The multiple CuO nanoplates and Ce-doped CuO nanoleaves were successfully synthesized by a simple and inexpensive chemical method. The as-synthesized CuO and 3 mol% Ce-doped CuO was applied for MB photodegradation under UV light. The photodegradation efficiency of 3 mol% Ce-doped CuO was 5.2 times higher than that of CuO.

Acknowledgments

We wish to thank Thailand's Office of the Higher Education Commission for financial support through the National Research University Project for Chiang Mai University, and the Research and Development Institute (RDI) of Bansomdejchaopraya Rajabhat University (BSRU) through the BSRU Research Fund.

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Synthesis and characterization of Ce-doped CuO nanostructures and their photocatalytic activities

Highlights

Abstract

Introduction

Section snippets

Experiment

Results and discussion

Conclusions

Acknowledgments

Ceram. Int.

Mater. Sci. Semicond. Process.

Mater. Sci. Semicond. Proc.

Mater. Chem. Phys.

Appl. Surf. Sci.

J. Coll. Interf. Sci.

Superlattices Microsruct.

Appl. Surf. Sci.

Ceram. Int.