Abstract

Reduced graphene oxide (rGO) in combination with palladium (Pd) thin film for the detection of hydrogen (H₂) has been widely reported; Pd-decorated rGO for carbon monoxide (CO) gas sensing is rarely discussed. This study reveals palladium nanoparticle-decorated rGO (rGO-Pd) detects CO gas easily for a wide range of temperatures (RT–150°C). The study also shows that the device detects CO with detection limit of 50 parts per million (ppm). Percentage response (%R) of pure rGO- and rGO-Pd-based sensors increase with both concentration and operating temperature increase. CO sensing of rGO also improves when decorated with Pd nanoparticles. Further, the increase in the %R in rGO-Pd is because of the synergistic electron exchange activity of rGO and Pd. New mechanistic insight into the dependence of sensing performance of rGO and rGO-Pd on pre-adsorbed oxygen species and baseline resistance drift at a particular temperature is proposed. The detailed analysis of the variation in adsorbed oxygen and number of electrons exchanged during CO molecule adsorption at different temperatures is discussed.

Graphical Abstract

中文翻译：

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rGO 和 Pd 修饰的 rGO 对一氧化碳气体的响应

摘要

还原氧化石墨烯 (rGO) 结合钯 (Pd) 薄膜用于检测氢 (H ₂) 已被广泛报道；很少讨论用于一氧化碳 (CO) 气体传感的 Pd 装饰 rGO。这项研究揭示了钯纳米颗粒修饰的 rGO (rGO-Pd) 可以在很宽的温度范围内 (RT–150°C) 轻松检测 CO 气体。该研究还表明，该设备检测 CO 的检测限为百万分之 50 (ppm)。纯 rGO 和 rGO-Pd 传感器的百分比响应 (%R) 随着浓度和工作温度的增加而增加。当用 Pd 纳米粒子装饰时，rGO 的 CO 传感也会得到改善。此外，rGO-Pd 中 %R 的增加是由于 rGO 和 Pd 的协同电子交换活性。提出了 rGO 和 rGO-Pd 传感性能对特定温度下预吸附氧物种和基线电阻漂移的依赖性的新机制见解。

图形概要