Abstract As(III) is a highly toxic and predominant arsenic species especially in anoxic groundwater. In this paper, the measurement of trace amount of As(III) was reported by using the Au-PANI-Fe-CNFs composite as sensing platform. The Au-PANI-Fe-CNFs composite was constructed by the formation of polyaniline (PANI) nanosheet array on the electrospun Fe-containing carbon nanofibers (Fe-CNFs) substrate followed by self-deposition of Au nanoparticle. PANI presents a uniform array structure on the fiber surface. Au nanoparticles were deposited uniformly on the PANI nanosheet surface by means of the reducing property of PANI, with the particle size of about 20 ± 6 nm. The presence of Fe in the CNFs accelerates the growth of PANI nanosheet and improves the As adsorption in the sensing process of As(III) thereafter. The obtained Au-PANI-Fe-CNFs exhibit excellent electrochemical performance for the detection of As(III) in water, because of the unique structure of PANI array and uniform distribution of AuNPs. The designed electrode displays wide linear range (5– 400 ppb) and high sensitivity with a detection limit of 0.5 ppb (S/N ≥ 3). This novel modified electrode shows a great opportunity for the electrochemical analysis of arsenic and its analogues in water.

中文翻译：

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用于测定 As(III) 的碳纳米纤维上的 AuNPs-聚苯胺纳米片阵列

摘要 As(III) 是一种剧毒且主要的砷种类，尤其是在缺氧地下水中。在本文中，使用 Au-PANI-Fe-CNFs 复合材料作为传感平台报告了痕量 As(III) 的测量。Au-PANI-Fe-CNFs复合材料是通过在电纺含铁碳纳米纤维（Fe-CNFs）基材上形成聚苯胺（PANI）纳米片阵列，然后自沉积Au纳米颗粒来构建的。PANI在纤维表面呈现出均匀的阵列结构。通过PANI的还原性，Au纳米颗粒均匀沉积在PANI纳米片表面，粒径约为20±6 nm。CNF 中 Fe 的存在加速了 PANI 纳米片的生长，并改善了其后 As(III) 传感过程中的 As 吸附。由于PANI阵列的独特结构和AuNPs的均匀分布，所获得的Au-PANI-Fe-CNFs在检测水中的As(III)方面表现出优异的电化学性能。设计的电极显示出较宽的线性范围 (5–400 ppb) 和高灵敏度，检测限为 0.5 ppb (S/N ≥ 3)。这种新型修饰电极为水中砷及其类似物的电化学分析提供了巨大的机会。