Optimal Thickness and Performance of Ppy/Go Gas Sensors for Coffee Aroma

Abstract:

This study presents the development and optimization of polypyrrole/graphene oxide (PPy/GO) gas sensors for accurate and reliable coffee aroma detection. By systematically varying the PPy/GO film thickness, we determined the optimal configuration to maximize sensor sensitivity and response time. The optimized sensor demonstrated exceptional performance in distinguishing coffee aromas from different plantations, highlighting its potential for applications in coffee quality control and aroma analysis. The PPy/GO composite was synthesized using a proven method and characterized using Fourier transform infrared spectroscopy (FTIR). Fabrication of the sensor involved a straightforward drop-coating technique that allowed precise control of film thickness. Susceptibility testing was performed under controlled conditions using coffee vapor at various concentrations. To evaluate the performance of the sensor in real-world scenarios, coffee samples from three different plantations were analyzed. Despite minor variations in sensor response due to inherent differences in coffee aroma profiles, the overall reproducibility and consistency of the measurements were extremely satisfactory. The %RSD values between 1.11% and 4.75% demonstrate the precision and reliability of the sensor. Keywords: Graphena Oxide, Polypirrole, gas sensor, coffee aroma, thickness optimization

• Periodical: Engineering Headway (Volume 24)
• Pages: 85-97
• DOI: https://doi.org/10.4028/p-5SkmH7
• Online since: July 2025
• Authors: Tri Mulyono*, Zona Salsabila Ardyanti, Zulfikar Zulfikar, Siswoyo Siswoyo, Asnawati Asnawati, Yeni Maulidah Muflihah
• Keywords: Coffee Aroma, Gas Sensor, Graphene Oxide, Polypirrole, Thickness Optimization

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