Gold Nanorods as an Efficient Substrate for the Detection and Degradation of Pesticides.

The rapid, ultralow detection, degradation, and complete removal of pesticides demand the design of potential substrates. Herein, we discussed gold nanorods (Au NRs) as the potential substrate for the naked eye detection and degradation of two common and broad-spectrum pesticides, chlorpyrifos (CPF) and malathion (MLT), up to 0.15 ppt concentration within 2 min. Under certain environmental conditions, both the pesticides degraded and adsorbed on the surface of Au NRs. The degraded moieties of CPF and MLT on the surface of Au NRs formed side-to-side and end-to-end interactions, respectively, leading to a long-range assembly. This shows that no external agent is required, and only CPF and MLT analytes are quite enough for the formation of assembly of Au NRs. Assembly of Au NRs is confirmed by transmission electron microscopy (TEM) analysis, and degradation is supported by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and gas chromatography-mass spectrometry (GC-MS) analyses. Au NRs were recovered and reused for four consecutive cycles. The fast and ultralow detection of pesticides demonstrates that Au NRs are a potential substrate for the detection and degradation of pesticides.

Controlled Synthesis of Palladium Nanocubes as an Efficient Nanocatalyst for Suzuki-Miyaura Cross-Coupling and Reduction of p-Nitrophenol.

Anisotropic nanocatalysts have attracted considerable attention in comparison to bulk/nanocatalysts for their enhanced activity and reactivity. The demand toward anisotropic palladium (Pd) nanostructures has increased rapidly in the field of catalysis. Pd is a well-known active catalyst for several carbon-carbon (C-C) cross-coupling reactions; among them, the Suzuki-Miyaura cross-coupling reaction is one of the most versatile and dominant methods for constructing the extraordinarily useful unsymmetrical biaryls and also for hydrogenation of organic contaminants like p-nitrophenol (p-NP). This paper provides a brief explanation about the controlled synthesis, characterization, and catalytic activity of well-defined palladium nanocubes (Pd NCs) prepared by a seed-mediated method. The synthesized monodispersed Pd NCs were characterized by spectroscopic and microscopic tools such as UV-visible, XRD, FESEM, HRTEM, and EDS analyses. Pd NCs proved as an efficient catalyst for Suzuki-Miyaura cross-coupling reactions and p-NP reduction. The catalyst shows enhanced activity, greater stability, and higher selectivity with remarkable recyclability up to 92% for five consecutive cycles. The catalytic performance of the synthesized Pd NCs was also studied in the reduction of the organic contaminant p-NP, which showed an excellent performance screening of 99% conversion in 6 min.