Tailoring MoS2 nanoflakes over MXenes nanobelts for efficient ammonia detection at room temperature

Abstract

Molybdenum disulfide (MoS₂) has emerged as a promising material for room-temperature gas sensing applications. However, its practical use is constrained by stability issues. To address this, the in-situ growth of MoS₂ nanoflakes on MXenes (Ti₃C₂) nanobelts is reported for efficient ammonia (NH₃) gas sensing applications under ambient conditions. The MoS₂ nanoflakes are grown successfully on Ti₃C₂ nanobelts via a facile one-step hydrothermal method and analyzed by state-of-the-art investigations. The design of the gas sensor is to anchor MoS₂/Ti₃C₂ onto a ceramic tube with a pair of gold electrodes. The results demonstrate that the sensor fabricated exhibits rapid, selective and stable response for NH₃ at room temperature. Specifically, the sensor shows a significant gas response (~10%) to 100 ppm NH₃, outperforming the pure MoS₂ based sensor (~7%). More importantly, the sensor maintains performance at 1 ppm NH₃, with a gas response of 2.5%, a response time of 10 seconds, and a recovery time of 7 seconds. These enhancements are attributed to the synergistic effects between MoS₂ and Ti₃C₂, which not only improve stability but also enhance gas sensing capabilities. This study elucidates the potential of MoS₂/Ti₃C₂ composites for achieving reliable and efficient NH₃ sensing at room temperature, paving the way for advanced gas sensing technology.