Laser-induced graphene electrodes for electrochemical ion sensing, pesticide monitoring, and water splitting

Abstract

Laser-induced graphene (LIG) has shown to be a scalable manufacturing route to create graphene electrodes that overcome the expense associated with conventional graphene electrode fabrication. Herein, we expand upon initial LIG reports by functionalizing the LIG with metallic nanoparticles for ion sensing, pesticide monitoring, and water splitting. The LIG electrodes were converted into ion-selective sensors by functionalization with poly(vinyl chloride)-based membranes containing K + and H + ionophores. These ion-selective sensors exhibited a rapid response time (10-15 s), near-Nernstian sensitivity (53.0 mV/dec for the K + sensor and − 56.6 mV/pH for the pH sensor), and long storage stability for 40 days, and were capable of ion monitoring in artificial urine. The pesticide biosensors were created by functionalizing the LIG electrodes with the enzyme horseradish peroxidase and displayed a high sensitivity to atrazine (28.9 nA/μM) with negligible inference from other common herbicides (glyphosate, dicamba, and 2,4-dichlorophenoxyacetic acid). Finally, the LIG electrodes also exhibited a small overpotential for hydrogen evolution reaction and oxygen evolution reaction. The oxygen evolution reaction tests yielded overpotentials of 448 mV and 995 mV for 10 mA/cm 2 and 100 mA/cm 2 , respectively. The hydrogen evolution reaction tests yielded 35 mV and 281 mV for the corresponding current densities. Such a versatile LIG platform paves the way for simple, efficient electrochemical sensing and energy harvesting applications.

Wearable Flexible Perspiration Biosensors Using Laser-Induced Graphene and Polymeric Tape Microfluidics

“…Sodium ionophore, NaTPB, PVC, and DOS (1%, 0.55%, 33%, 65.45%) for a total mass of 100 mg were dissolved in 660 μL of THF and gently sonicated in an ultrasonic bath for ∼3 min to fully homogenize the ion selective membrane (ISM) in a procedure developed for previously reported potassium and ammonium ISM's. 65 ISM was applied to freshly prepared LIG working electrodes in 5 μL coats. Three coats were applied to avoid pinhole formation, and large bubbles were gently dissipated with a needle.…”

Doping of Laser‐Induced Graphene and Its Applications

“…[220] Meanwhile, Kucherenko et al reported the versatile LIG platform functionalized with metallic NPs for ion sensing, pesticide monitoring, and water splitting. [221] The fabrication of multifunctional sensors included thermal decomposition of nickel(II) acetate tetrahydrate and an electroless deposition method for Pt, as shown in Figure 13a. For the application of EMI shielding, [92] the LIG-Fe 3 O 4 composite obtains the EMI shielding effectiveness of 32.7 dB.…”

Biosensors Based on Graphene Nanomaterials

“…Biosensors for pesticides were created [ 98 ] by functionalizing LIG electrodes with the enzyme horseradish peroxidase. They showed a high level of sensitivity to atrazine (28.9 na/μm) with little difference from other common herbicides (glyphosate, dicamba and 2,4-dichlorophenoxyacetic acid).…”