Synthesis of N-rGO-MWCNT/CuCrO2 Catalyst for the Bifunctional Application of Hydrogen Evolution Reaction and Electrochemical Detection of Bisphenol-A

Subramanian Sakthinathan,Shen-Ming Chen,Arjunan Karthi Keyan,Chaofang Dong,Sivaramakrishnan Vinothini,Te-Wei Chiu,Ramachandran Rajakumaran

doi:10.3390/catal11030301

Abstract

A glassy carbon electrode (GCE) coated with delafossite CuCrO2 loading on the nitrogen-doped reduced graphene oxide (N-rGO) and multiwalled carbon nanotubes (MWCNT) composite (N-rGO-MWCNT/CuCrO2) was applied to the hydrogen evolution reaction and Bisphenol-A (BPA) detection. First, the N-rGO-MWCNT composite was prepared by in situ chemical reduction with caffeic acid as a reducing agent. Then, CuCrO2 was accumulated on the N-rGO-MWCNT surface to form N-rGO-MWCNT/CuCrO2 composite. The morphology structure of the N-rGO-MWCNT/ CuCrO2 composite was analyzed by different characterization techniques. Besides, the GCE/N-rGO-MWCNT/CuCrO2 composite electrode was investigated for hydrogen evolution reaction (HER), which shows an excellent electrocatalytic activity with a low over-potential, increasing reduction current, and a small Tafel slope of 62 mV·dec−1 at 10 mA·cm−2 with long-term stability. Moreover, the electrochemical determination of BPA was in the range of 0.1-110 µM, and low detection limit of 0.033 µM (S/N = 3) with a higher sensitivity of 1.3726 µA µM−1 cm−2. Furthermore, the prepared GCE/N-rGO-MWCNT/CuCrO2 electrode shows effective detection of BPA in food samples with acceptable recoveries. Hence, the finding of GCE/N-rGO-MWCNT/CuCrO2 can be observed as an impressive catalyst to the electrocatalytic activity of HER and BPA oxidation.

Highlights

Increasing the energy crisis, environmental pollution, climate change, and energy shortages by excessive fossil fuel consumption, so the need to seek clean, cheap, safe and viable renewable energy resources has become very important [1]
The typical X-ray Diffraction (XRD) patterns of multiwalled carbon nanotubes (MWCNT) display (002) and (100) peaks were found at 26.33◦ and 43.69◦, respectively
The XRD pattern of the nitrogendoped reduced graphene oxide (N-reduced graphene oxide (rGO))-MWCNT/CuCrO2 composite observes the Catalysts 2021, 11, x FOR PEER REVIrEeWflections corresponding to the N-rGO-MWCNT and CuCrO2 crystalline pe4aokf 2s1validate that the composite formation

Summary

Introduction

Increasing the energy crisis, environmental pollution, climate change, and energy shortages by excessive fossil fuel consumption, so the need to seek clean, cheap, safe and viable renewable energy resources has become very important [1]. Among the numerous carbon materials, reduced graphene oxide (rGO) has received more attention such as high surface area, interconnected macroporous structures, higher stability, and conductivity [29,30,31]. Various types of techniques, such as immune sensors, molecular imprinting process, high-performance liquid chromatography (HPLC), mass spectrometry, and electrochemical methods have currently been used to detect BPA [48,49]. Among these methods of detection, electrochemical BPA detection has greater attention with simple planning, low cost, rapid reaction, surface renewal ease, bulk adjustment, high sensitivity, and selectivity [50]. The electrodes of GCE/N-rGO-MWCNT/ CuCrO2 demonstrated impressive electrochemical sensor properties and sensitivity in BPA detection. The GCE/N-rGO-MWCNT/CuCrO2 electrode exhibited an excellent electrocatalytic response toward the HER and BPA detection

Results and Discussion

TEM and STEM Studies

FT-IR and Raman Studies

XPS Studies

Electrochemical Impedance Spectroscopy Studies

Hydrogen Evolution Reaction