Graphene nanoplatelet supported CeO2 nanocomposites towards electrocatalytic oxidation of multiple phenolic pollutants

doi:10.1016/j.aca.2019.08.024

Analytica Chimica Acta

Volume 1088, 11 December 2019, Pages 45-53

https://doi.org/10.1016/j.aca.2019.08.024 Get rights and content

Highlights

•
Facile synthesis of CeO₂ nanocubes, nanopolyhedras and nanorods.
•
Morphology-dependent electrochemistry of CeO₂ nanostructures.
•
Sensitive and selective monitoring of different environmental pollutants.

Abstract

To explore suitable sensing materials for sensitive and selective detection of phenolic pollutants, CeO₂ nanocubes, nanopolyhedras, and nanorods were synthesized by a hydrothermal method. These CeO₂ nanomaterials were further loaded on the support of graphene nanoplatelets. As-synthesized nanomaterials and nanocomposites were characterized using transmission electron microscopy, X-ray diffraction and Raman spectroscopy as well as electrochemical techniques including cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The nanocomposite of graphene nanoplatelets with CeO₂ nanorods shows the highest electrochemical activity towards soluble species. Highly sensitive and selective determination of tetrabromobisphenol A, catechol, diethylstilbestrol, and nonylphenol was thus achieved at this nanocomposite based electrode. Their limits of detection were as low as 1.8, 42, 1.5 and 2.7 nM, respectively. Such an electrochemical sensor is thus promising for simple, fast and sensitive electrochemical determining of trace-leveled phenolic pollutants in water samples.

Graphical abstract

Introduction

In recent years, sustained industrial development has produced tremendous economic benefits but accompanied by the formation of a large number of emerging contaminants, including flame retardants, endocrine disrupting chemicals (EDCs), pharmaceuticals, and personal care products (PPCPs). Among them, phenol derivatives have the biggest amounts but vary at different concentrations [1]. For example, the concentrations of phenol derivatives dissolved in water are actually low. However, they still threaten to human health, owing to their high toxicity and carcinogenicity [2]. Strict requirements have been thus set for the maximum content of these contaminants in natural water [3,4]. Take tetrabromobisphenol A (TBBPA) as an example, it is extensively used as a brominated flame retardant in the electronics, textiles, and other fields [5]. Meanwhile, it is regarded as an endocrine disruptor [6]. Moreover, TBBPA can cause adverse effects such as immunotoxicity [7], neurotoxicity [8], and developmental toxicity [9]. Surprisingly, TBBPA is still extensively applied in different fields, leading to a sharp increase of its content in environmental wastewater. Therefore, it is of great significance to monitor TBBPA at different concentration levels.

Up to now, many traditional techniques such as high performance liquid chromatography [10], liquid chromatography-mass spectrometry [11,12], gas chromatography-mass spectrometry [13], and electroanalysis [14,15] have been utilized for the detection of phenol derivatives. Compared with these techniques, an electrochemical method is more efficient and promising since it is cost-effective, sensitive, convenient, and rapid [16,17]. To develop electrochemical sensors with these features to detect TBBPA, the selection of suitable sensing materials is the first key issue. For example, the size, morphology, and crystal structure of nanomaterials affect significantly their performance and applications in the fields of catalysis, energy storage, and sensing [18,19]. The morphology control of nanomaterials has actually become extremely important during the synthesis of nanomaterials [20]. Of special interests, the application of these nanomaterials (e.g., inorganic metal oxide nanoparticles) with different morphologies has received considerable attention in the field of catalysis [[21], [22], [23], [24], [25], [26], [27]]. This is because the catalysts with different morphologies own varied electronic structures, surface atomic arrangement, adsorption active sites, comparative areas, and exposed crystal faces. Even for one same catalytic reaction, the catalytic steps (or catalytic activity and efficiency) are thus changed on these nanomaterials [[21], [22], [23], [24], [25], [26], [27]]. Among them, cerium dioxide (CeO₂) nanomaterial is one of extensively utilized since it possesses excellent redox ability, unique optical properties, and chemical stability [[28], [29], [30]]. Surprisingly, its electrochemical sensing applications are seldom reported.

On the other hand, an electrochemical sensor needs a suitable support to load sensing materials (e.g., nanomaterials) in most cases. One of the best solutions is to form the nanocomposite of the support and the used sensing materials. Under these conditions, graphene nanoplatelet (GNP) is one of optimal candidates in that it owns unique two-dimensional structure, and excellent physical and chemical properties (e.g., high electrical conductivity, extraordinary electrocatalytic activity, and huge specific surface area) [31]. If GNPs are employed as the support to load nanomaterials (e.g., CeO₂), the force between GNPs layers is possible to be undermined. In other words, nanomaterials can also reduce the stacking of GNPs. The synergetic effect probably existed inside the composite of the support (e.g., GNP) and the sensing materials (e.g., CeO₂) eventually enables sensitive, stable, and reproducible electrochemical sensing.

Herein, the electrochemical sensing performance of GNPs supported CeO₂ nanomaterials towards phenolic pollutants is reported. The detected phenolic pollutants include TBBPA, catechol (CC), diethylstilbestrol (DES), and nonylphenol (NP). The used CeO₂ nanomateirals, synthesized by mean of a hydrothermal process, have three different morphologies (namely CeO₂ nanocubes, nanopolyhedras, and nanorods). As expected, GNPs supported CeO₂ nanomaterials exhibited different electrocatalytic (sensing) performance towards these phenolic pollutants, indicating morphology-dependent sensing performance. The CeO₂ nanorod/GNP nanocomposite showed the best electrochemical sensing ability. A sensing platform with high sensitivity, selectivity, and stability for electrochemical determination of these pollutants in wide concentration ranges was thus constructed.

Section snippets

Materials

All chemicals were of analytical grade and used as received. TBBPA was offered from the Laboratory of Dr. Ehrenstorfer (German). DES, NP, and CC were purchased from Aladdin Chemistry Co., Ltd. (Shanghai, China). GNPs were obtained from Nanjing Xi Nano Mstar Technology Ltd (Nanjing, China). Ultrapure water (18.2 MΩ cm) was obtained from a Milli-Q water purification system and used throughout.

Three CeO₂ nanomaterials were prepared by a reported hydrothermal method [32] where Ce(NO₃)₃·6H₂O and

Results and discussion

To inspect the morphologies and microstructures of CeO₂ nanomaterials, their TEM and high-resolution TEM (HRTEM) images were recorded. Obviously, these CeO₂ nanomaterials show distinguished morphologies. The synthesized CeO₂ nanomaterials in Fig. 1A are cubic. Their sizes are somehow different. The estimated average size is about 20 nm. They are thus named as CeO₂ nanocubes. Differently, the nanomaterials in Fig. 1B are uniform and polyhedras. These CeO₂ polyhedras have a size of about 10 nm.

Conclusion

Three CeO₂ nanomaterials, namely CeO₂ nanocubes, nanopolyhedras, and nanorods have been synthesized by a hydrothermal method and further applied sensing materials for the detection of phenolic pollutants. Supported by graphene nanoplatelets, these CeO₂ nanomaterials showed morphology-dependent electrochemistry. On the nanocomposite of graphene nanoplatelets and CeO₂ nanorods based electrode, a sensitive and selective electrochemical sensor has been established for the detection of

Declaration of interest statement

All financial supports have been stated. There are no any personal relationships with other people or organizations inappropriately influenced this work.

Conflict of interest

All the authors state that that there are no conflicts of interests.

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (NO. 61701352) and Graduate Innovative Fund of Wuhan Institute of Technology of China (NO. CX2018153 and CX2018160).

References (52)

L. Martin-Pozo et al.
Analytical methods for the determination of emerging contaminants insewage sludge samples
Talanta
(2019)
A. Stasinakis
Review on the fate of emerging contaminants during sludge anaerobic digestion
Bioresour. Technol.
(2012)
F. Kong et al.
Facile green synthesis of graphene-titanium nitridehybrid nanostructure for the simultaneous determination of acetaminophen and 4-aminophenol
Sens. Actuators B Chem.
(2015)
M. Taheran et al.
Emerging contaminants: here Today, there tomorrow
Environ. Nanotechnol., Monit. Manag.
(2018)
A. Nakajima et al.
Neurobehavioral effects of tetrabromobisphenol A, a brominated flame retardant, in mice
Toxicol. Lett.
(2009)
S. Pullen et al.
The flame retardants tetrabromobisphenol A and tetrabromobisphenol A-bisallylether suppress the induction of interleukin-2 receptor α chain (CD25) in murine splenocytes
Toxicology
(2003)
J. McCormick et al.
Embryonic exposure to tetrabromobisphenol A and its metabolites, bisphenol A and tetrabromobisphenol A dimethyl ether disrupts normal zebrafish (Danio rerio) development and matrix metalloproteinase expression
Aquat. Toxicol.
(2010)
H. Sambe et al.
Simultaneous determination of bisphenol A and its halogenated derivatives in river water by combination of isotope imprinting and liquid chromatography-mass spectrometry
J. Chromatogr., A
(2006)
G. Mascolo et al.
New perspective on the determination of flame retardants in sewage sludge by using ultrahigh pressure liquid chromatography-tandem mass spectrometry with different ion sources
J. Chromatogr. A
(2010)
Z. Xie et al.
Trace determination of the flame retardant tetrabromobisphenol A in the atmosphere by gas chromatography-mass spectrometry
Anal. Chim. Acta
(2007)

D. Jiang et al.

Simultaneous biosensing of catechol and hydroquinone via a truncated cube-shaped Au/PBA nanocomposite

Biosens. Bioelectron.

(2019)

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Graphene nanoplatelet supported CeO2 nanocomposites towards electrocatalytic oxidation of multiple phenolic pollutants

Highlights

Abstract

Graphical abstract

Introduction

Section snippets

Materials

Results and discussion

Conclusion

Declaration of interest statement

Conflict of interest

Acknowledgements

Talanta

Bioresour. Technol.

Sens. Actuators B Chem.

Environ. Nanotechnol., Monit. Manag.

Toxicol. Lett.

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Aquat. Toxicol.

J. Chromatogr., A

J. Chromatogr. A

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J. Power Sources

Biosens. Bioelectron.

Powder Technol.

Mater. Res. Bull.

Appl. Surf. Sci.

Chem. Eng. J.

Electroanalysis

Chem. Eng. J.

Carbon

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Ionics

Biosens. Bioelectron.

Graphene nanoplatelet supported CeO₂ nanocomposites towards electrocatalytic oxidation of multiple phenolic pollutants