Detection of heavy metals such as Pb⁺² is critical due to their high toxicity as even trace amounts of them pose a serious detrimental risk to human health. Pb²⁺ is one of the major toxic and persistent pollutants generated from industry and commonly found in soil, drinking water, and aquatic environments. Due to its high-mobility and one-atom thickness, graphene (Gr) based materials have shown great potential for chemical sensors of heavy metals. Recently, a novel conductive reduced-GO obtained by chemical vapor deposition (CVD-rMGO) showed improved layering structure and conductivity over conventional rGO based on chemically exfoliated flakes. Herein, utilizing this novel rGO obtained from chemical vapor deposition, we showed improved Pb²⁺ detection using both electrochemical and conductivity sensing. For electrochemical sensing, a CVD-rMGO film is used as working electrode and cyclic voltammetry is used to detect Pb⁺² ions accumulated on the CVD-rMGO, obtaining a sensitivity of 4.6 nA nM⁻¹cm⁻² and a calculated limit of detection of 0.21 nM. For electrical sensing, the drain current through a CVD-rMGO was monitored as the film as exposed to different concentrations of Pb⁺², reaching an estimated limit of detection of 0.101 nM. This work shows that high-quality reduced graphene oxide produced by chemical vapor deposition can serve as a basis enable high-sensitivity detectors of Pb²⁺.

由于重金属如Pb ⁺²的高毒性，因此对其进行检测至关重要，因为即使痕量的重金属也对人体健康构成严重的有害风险。Pb ²⁺是工业产生的主要有毒和持久性污染物之一，通常存在于土壤，饮用水和水生环境中。由于其高迁移率和一个原子的厚度，基于石墨烯（Gr）的材料在重金属化学传感器方面显示出了巨大的潜力。最近，通过化学气相沉积（CVD-rMGO）获得的新型导电还原GO表现出比基于化学剥落薄片的常规rGO更好的分层结构和导电性。在本文中，利用从化学气相沉积获得的新型rGO，我们显示出改善的Pb ²⁺使用电化学和电导率检测进行检测。对于电化学感测，将CVD-rMGO膜用作工作电极，并使用循环伏安法检测CVD-rMGO上积累的Pb ⁺²离子，获得4.6 nA nM ^-1 cm ^-2的灵敏度和计算出的检测极限为0.21 nM。对于电感应，当薄膜暴露于不同浓度的Pb ^+2时，监测通过CVD-rMGO的漏极电流，达到估计的检测极限0.101 nM。这项工作表明，通过化学气相沉积产生的高质量还原氧化石墨烯可以作为启用Pb ²⁺高灵敏度检测器的基础。