3D printed carbon black-polylactic acid/copper (CB-PLA/Cu) sensor for improved sustainability in monitoring photocatalytic hydrogen peroxide evolution
Pádraig McDonagh, Matthew McCole, Nathan Skillen, Peter K.J. Robertson, Denis McCrudden
Abstract
As the photocatalytic generation of hydrogen peroxide 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 carbon black-poly lactic acid/copper sensor with an extremely low fabrication cost of €0.012 was employed to accurately monitor the photocatalytic evolution of hydrogen peroxide. The accuracy was confirmed through strong correlation with a standard fluorescence spectroscopic method. The sensor displayed limit of detection and limit of quantification values of 0.24 µM and 0.79 µM respectively, and a sensitivity of 217 µA mM-1 cm2, while also showing strong selectivity towards hydrogen peroxide in the presence of potential interfering species. 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 hydrogen peroxide presents as a more economical and sustainable alternative to current methods.