Hu Xiaopeng,Xia Yide,Liu Yiwei,Zhao Faqiong,Zeng Baizhao
A novel dual-dummy templates imprinted electrochemical sensor has been fabricated for the detection of patulin. Herein, 2-oxindole (2-oxin) and 6-hydroxynicotinic acid (6-HNA) as the dummy templates, 4-aminothiophenol as functional monomer, and ionic liquid (IL) as electropolymerization electrolyte are employed to prepare molecularly imprinted polymer (MIP) film. 2-Oxin and 6-HNA have multiple groups and the obtained MIP possesses different types of imprinted sites, thereby achieving a better recognition capacity than that of single-dummy imprinted film. ILs can regulate the density of molecularly imprinted film and facilitate effective molecular recognition. The composite of PtPd decorated N-doped porous carbon has good conductivity and large surface area, and can amplify the signal. With the aid of electrochemical probe [Fe(CN) 6 ] 3-/4- (0.16 V vs. SCE) patulin can be detected. Under the optimal conditions, this sensor shows a detection range from 0.01 to 10 μg L −1 , with a detection limit of 7.5 × 10 −3 μg L −1 ( S / N = 3). Two spiked juice samples were analyzed by this method, and the recovery ranges from 94 to 99.8% with RSD values of 2.4–4.6% ( n = 3), indicating that this method can be applied for the detection of patulin in real samples. Graphical abstract
A novel dual-dummy templates imprinted electrochemical sensor is firstly fabricated for the detection of patulin. This sensor exhibits high recognition capacity and sensitivity.
Graphical PtPd-decorated multibranched Au@Ag nano-heterostructures were successfully synthesized by using a seed growth method and chemical reduction method. By adjusting the distribution position of PtPd nanoparticles, the hydrogen evolution performance of the heterostructure is optimized. These electrocatalysts revealed excellent hydrogen evolution reaction under visible and near infrared light due to the structural effect, photoelectric effect, and photothermal effect. PtPd-decorated multibranched Au@Ag nanocrystals (NCs) were synthesized to form heterostructures with enhanced electrochemical performance for water splitting in the visible/near infrared (vis-NIR) light region. Three kinds of heterostructures including PtPd-covered, PtPd-edged, and PtPd-tipped Multi-branched Au@Ag NCs were fabricated by controlling the growth process of PtPd alloy nanoparticles on Au@Ag NCs. PtPd-covered Multi-branched Au@Ag nanocrystal exhibited the best photo-assisted electrocatalytic activity. The initial overpotential under vis-NIR light is 33 mV with a Tatel slope of 101 mV/dec while the overpotential is 150 mV at 10 mA cm −2 . The enhanced catalyst activity is ascribed to samples with heterogeneous structures and changed morphology and composition. In addition, localized surface Plasmon resonance (LSPR) effect from the surface of samples resulted in the effective separation of electron-hole pairs (photoelectric effect). Finally the photothermal effect generated from the absorbance of Au nanostructures in near-infrared light increased the temperature of the catalyst. The synergy of structure, photoelectricity, and photothermal effect endows the catalyst with excellent photo-assisted electrocatalytic activity.
危险品化学品经营许可证（带存储）