Exploring MOF-Derived CuO/rGO Heterostructures for Highly Efficient Room Temperature CO2 Sensors.

Abstract

In response to the urgent need for advanced climate change mitigation tools, this study introduces an innovative CO2 gas sensor based on p-p-type heterostructures designed for effective operation at room temperature. This sensor represents a significant step forward, utilizing the synergistic effects of p-p heterojunctions to enhance the effective interfacial area, thereby improving sensitivity. The incorporation of CuO nanoparticles and rGO sheets also optimizes gas transport channels, enhancing the sensor's performance. Our CuO/rGO heterostructures, with 5 wt % rGO, have shown a notable maximum response of 39.6-500 ppm of CO2 at 25 °C, and a low detection limit of 2 ppm, indicating their potential as high-performance, room-temperature CO2 sensors. The prepared sensor demonstrates long-term stability, maintaining 98% of its initial performance over a 30-day period when tested at 1-day intervals. Additionally, the sensor remains stable under conditions of over 40% relative humidity. Furthermore, a first-principles study provides insights into the interaction mechanisms with CO2 molecules, enhancing our understanding of the sensor's operation. This research contributes to the development of CO2 monitoring solutions, offering a practical and cost-effective approach to environmental monitoring in the context of global climate change efforts.