Facile Synthesis of Porous Hexapod Ag@AgCl Dual Catalysts for In Situ SERS Monitoring of 4-Nitrothiophenol Reduction

Abstract

<jats:p>Controllable morphological metal catalytic materials have always been a focus in research. In the previous work, hexapod AgCl was successfully synthesized. In this paper, hexapod Ag@AgCl microstructures with diverse Ag contents are prepared through NaBH4 reduction. They are characterized by scanning electron microscopy (SEM) and the element distribution is proved by an energy dispersive X-ray spectrometer (EDS). They are porous dendritic microstructures with a large specific surface area and a rough surface, which display high catalytic performance and surface-enhanced Raman spectroscopy (SERS) activity. Furthermore, the hexapod Ag@AgCl microstructure is devoted as a dual catalyst to monitor the reduction of 4-nitrothiophenol (4-NTP) to 4-aminothiophenol (4-ATP) in situ using SERS. Ultraviolet–visible (UV–Vis) spectroscopy was employed to evaluate the catalytic performance of the hexapod Ag@AgCl microstructures. The consequences show that the velocity of reaction became faster with a corresponding increase in silver content and the reaction mechanism was cleared. In addition to preparing a good catalyst, this work also promotes the combination of micro-nano materials and spectroscopy technology.</jats:p>

An Adversarial Learning Approach for Super-Resolution Enhancement Based on AgCl@Ag Nanoparticles in Scanning Electron Microscopy Images

“…For the nanoparticles SEM images, 4000 pairs of images (1280 × 960 pixels) were separated into the training set (3940), validation set (20), and test set (40). Then we randomly cropped and rotated all the images into a total of 120,000 pairs of partial-overlapping patches (HR: 296 × 296 pixels, LR: 74 × 74 pixels) for data augmentation; 1200 pairs of these patches were removed from the datasets due to the severe blur and color deviation between the images.…”

“…Based on the research of our colleagues [39,40], with the increase of Ag nanoparticles on an AgCl@Ag microstructure, its catalytic activity will become better. In this article, we prepared two AgCl@Ag particles with different Ag content by adjusting the molar ratio of NaBH 4 to AgCl, labeled AgCl@Ag-1 and AgCl@Ag-2 respectively (see details in Supplementary Material Figures S1-S3).…”