Aim and shoot: molecule-imprinting polymer coated MoO3 for selective SERS detection and photocatalytic destruction of low-level organic contaminants
Aim and shoot: molecule-imprinting polymer coated MoO3 for selective SERS detection and photocatalytic destruction of low-level organic contaminants
复制标题
瞄准和射击：分子印迹聚合物涂层 MoO3 用于选择性 SERS 检测和低浓度有机污染物的光催化破坏
DOI：
10.1039/c7ra05547a
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发表时间：
2017-01-01
期刊：
影响因子：
3.9
通讯作者：
Zhang, Jinlong
中科院分区：
文献类型：
--
作者：
Wang, Lingzhi;Xu, Yin;Zhang, Jinlong
由于在复杂的检测环境中具有巨大的应用潜力，因此高度需要一种易于回收且具有良好灵敏度和选择性的SERS传感器。本文以亚甲基蓝（MB）为模型靶标，设计并制备了一种由MoO3纳米棒核和厚度为4 nm的均匀分子印迹聚甲基丙烯酸壳（MIP）组成的半导体SERS底物（MoO3@MIP），实现了选择性检测。超薄均匀MIP壳成功涂层的关键在于用硝酸预处理MoO3核，为聚合物前驱体的锚定提供足够的表面羟基。由于MoO3半导体的光催化降解，只需光照射即可形成MB的分子印迹空隙。这种核壳MIP复合材料在混合MB/CV溶液中对低水平MB具有较高的SERS选择性。增强因子（EF）很高，为1.6 × 104。更重要的是，选择性检测允许以“瞄准射击”的方式进一步光催化回收MoO3@MIP，这很好地保留了对MB的检测选择性和灵敏度至少4个循环。基于灵敏度随壳厚（10 ~ 24 nm）的增加而降低，提出了一种mip门控电荷转移机制来证明高EF而不是分子富集效应。这种“瞄准射击”策略有望推动选择性SERS在多种环境中用于痕量检测的繁荣应用。
A sensitive and selective SERS sensor with easy and excellent recyclability is highly demanded because of its great potential application in complex detection environments. Here, using methylene blue (MB) as a model target, a semiconductor-based SERS substrate composed of a MoO3 nanorod core and a uniform molecule-imprinting polymethacrylic acid shell (MIP) with a thickness of 4 nm was designed and fabricated (MoO3@MIP) to achieve selective detection. The key to the successful coating of the ultrathin uniform MIP shell lies in the pretreatment of a MoO3 core with nitric acid, providing sufficient surficial hydroxyls for the anchoring of a polymer precursor. The molecule-imprinted voids for MB were formed simply via light irradiation as a result of photocatalytic degradation by a MoO3 semiconductor. This core–shell MIP composite shows a high SERS selectivity towards low-level MB in a mixed MB/CV solution. The enhanced factor (EF) is high, at 1.6 × 104. More importantly, the selective detection allows the further photocatalytic recycling of MoO3@MIP in an “aim-and-shoot” way, which well preserves the detection selectivity and sensitivity towards MB at least for 4 cycles. Based on decreased sensitivity with the increasing shell thickness (10–24 nm), a MIP-gating charge transfer mechanism is proposed to demonstrate the high EF instead of the molecule-enrichment effect. This “aim-and-shoot” strategy is expected to push forward the prosperous application of selective SERS for trace detection in versatile environments.