Batch-to-Batch Variation in Laser-Inscribed Graphene (LIG) Electrodes for Electrochemical Sensing

Area of Science:

• Materials Science
• Electrochemistry
• Sensor Technology

Background:

• Laser-inscribed graphene (LIG) is a promising material for micro-electronics, including sensors.
• The batch-to-batch consistency of LIG quality is not well-documented, hindering scalable applications.

Purpose of the Study:

• To characterize the batch-to-batch variation in the manufacturing of LIG electrodes for electrochemical sensing.
• To investigate the impact of metallization on LIG electrode performance and variability.

Main Methods:

• Synthesis of numerous LIG electrode batches using a CO2 laser on polyimide film.
• Characterization via goniometry, stereomicroscopy, open circuit potentiometry, and cyclic voltammetry.
• Evaluation of two platinum electrodeposition techniques (galvanostatic, frequency-modulated).

Main Results:

• Unmetallized LIG electrodes exhibited less than 5% batch-to-batch variation.
• Metallization significantly increased peak current and specific capacitance.
• Batch-to-batch variation increased to approximately 30% after metallization.

Conclusions:

• A significant tradeoff exists between enhanced performance and increased batch variability in metallized LIG electrodes.
• This variability is a critical consideration for scaling LIG sensor designs for mass production.
• Further research is needed to understand and mitigate variability for improved quality control.