Optimizing Carbon Structures in Laser-Induced Graphene Electrodes Using Design of Experiments for Enhanced Electrochemical Sensing Characteristics

Fantinelli Franco, Fabiane; Malik, Muhammad Hassan; Manjakkal, Libu; Roshanghias, Ali; Smith, Cindy J.; Gauchotte-Lindsay, Caroline

Abstract

In this study, we explored the morphological and electrochemical properties of carbon-based electrodes derived from laser-induced graphene (LIG) and compared them to commercially available graphene-sheet screen-printed electrodes (GS-SPEs). By optimizing the laser parameters (average laser power, speed, and focus) using a design of experiments response surface (DoE-RS) approach, binder-free LIG electrodes were achieved in a single-step process. Traditional trial-and-error methods can be time-consuming and may not capture the interactions between all variables effectively. To address this, we focused on linear resistance and substrate delamination to streamline the DoE-RS optimization process. Two LIGs, designated LIG A and LIG B, were fabricated using distinct and optimized laser settings, which resulted in a sheet resistance of 25 ± 2 Ω/sq and 21 ± 1 Ω/sq, respectively. These LIGs, characterized by scanning electron microscopy, Raman spectroscopy, and contact angle analysis, exhibited a highly porous morphology with 13% pore coverage and a contact angle <50°, which significantly increased their hydrophilicity when compared to the GS-SPE. For the electrochemical studies, the oxidation of NO2– ion by the graphene-based working electrodes was investigated, as it allowed for the direct comparison of the LIGs to the GS-SPE. These included cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulsed voltammetry studies, which revealed that LIG electrodes displayed a remarkable 500% increase in peak current during NO2– oxidation compared to the GS-SPE. The LIGs also demonstrated improved stability and sensitivity (420 ± 30 and 570 ± 10 nAμM–1 cm–2) compared to the GS-SPE (73 ± 4 nAμM–1 cm–2) in the oxidation of NO2– ions; however, LIG B was more susceptible to ionic interference than LIG A. These findings highlight the value of applying statistical approaches such as DoE-RS to systematically improve the LIG fabrication process, enabling the rapid production of optimized LIGs that outperform conventional carbon-based electrodes.

Citation

Fantinelli Franco, F., Malik, M. H., Manjakkal, L., Roshanghias, A., Smith, C. J., & Gauchotte-Lindsay, C. (2024). Optimizing Carbon Structures in Laser-Induced Graphene Electrodes Using Design of Experiments for Enhanced Electrochemical Sensing Characteristics. ACS applied materials & interfaces, 16(47), 65489 - 65502. https://doi.org/10.1021/acsami.4c13124

• Journal Article Type: Article
• Acceptance Date: Oct 29, 2024
• Online Publication Date: Nov 14, 2024
• Publication Date: Nov 27, 2024
• Deposit Date: Nov 19, 2024
• Publicly Available Date: Nov 19, 2024
• Journal: ACS Applied Materials & Interfaces
• Print ISSN: 1944-8244
• Electronic ISSN: 1944-8252
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 16
• Issue: 47
• Pages: 65489 - 65502
• DOI: https://doi.org/10.1021/acsami.4c13124
• Keywords: screen printing, laser-induced graphene, design of experiments, nitrite detection, graphene and graphitic structures, electrochemical studies