3d Printed Cb-Pla/Cu Sensor for Improved Sustainability in Monitoring Photocatalytic Hydrogen Peroxide Evolution

As the photocatalytic generation of H₂O₂ continues to gather increasing interest, there is a significant need to introduce more sustainable methods to monitor the reaction process. The fabrication of low-cost sustainable electrochemical sensors offers an enticing alternative to the current standard methods. This study reports the first use of an electrochemical sensor to monitor such a process. A highly reproducible 3D printed CB-PLA/Cu sensor with an extremely low fabrication cost of €0.012 was employed to accurately monitor the photocatalytic evolution of H₂O₂. The accuracy was confirmed through strong correlation with a standard fluorescence spectroscopic method. The sensor displayed LOD and LOQ values of 0.24 µM and 0.79 µM respectively, and a sensitivity of 204 µA cm² mM^-1, while also showing strong selectivity towards H₂O₂ in the presence of potential interferents. Moreover, the electrocatalytic surface was capable of ≥3x regeneration without significant loss in activity bringing a ≥75% decrease in analysis cost and a significant reduction in potential waste material. This novel approach to monitoring the photocatalytic evolution of H₂O₂ presents as a more economical and sustainable alternative to current methods.