High-Yield Seedless Synthesis of Triangular Gold Nanoplates through Oxidative Etching

Abstract

We demonstrate that monodispersed triangular gold nanoplates with high morphological yield (>90%) can be synthesized through a rapid one-pot seedless growth process. The edge length of triangular Au nanoplates can be readily tuned between 40 and 120 nm by varying the reaction parameters. Systematic studies reveal that distinct from previous hypothesis that the formation of nanoplates is mainly determined by the selective binding of iodide ions, our results show that iodide ions could have dual functions: it can selectively bind to the Au {111} facets and also selectively remove other less stable shape impurities through oxidative etching by forming tri-iodide ions (I(3)(-)), thus facilitating the formation of nuclei with dominant planar structure. This new synthetic route will not only help to better understand the growth mechanism of triangular gold nanoplates but also promote the research in anisotropic noble metal nanostructures.

Polyvinylpyrrolidone-induced anisotropic growth of gold nanoprisms in plasmon-driven synthesis

“…4b(ii)). These results suggest that iodide promotes triangular nanoprism growth by passivating Au {111} facets 22,[42][43][44] . Such clear delineation between the adsorption locations of these two surface species highlights the merits of combining complementary capping agents to tune nanocrystal growth via this plasmon-driven synthesis strategy.…”

Improving the rates of Pd-catalyzed reactions by exciting the surface plasmons of AuPd bimetallic nanotriangles

“…Au nanotriangles were synthesized by following a literature procedure. 40 Briey, aqueous CTAC (16.0 mL, 0.10 M) was dissolved in 20.0 mL Milli-Q water in a 250 mL Erlenmeyer ask. To this solution, aqueous solutions of KI (0.75 mL, 0.1 M), HAuCl 4 (0.80 mL, 25.4 mM) and NaOH (0.20 mL, 0.10 M) were added sequentially.…”

“…40 Here, ascorbic acid was used as the reducing agent and potassium iodide as an oxidative etchant in the presence of air. To synthesize the AuPd bimetallic nanotriangles, K 2 PdCl 4 was reduced onto the as-synthesized Au nanotriangles using ascorbic acid as the reducing agent.…”

Shape controlled synthesis of porous tetrametallic PtAgBiCo nanoplates as highly active and methanol-tolerant electrocatalyst for oxygen reduction reaction

“…, “nanoplates” and their reduction in efficiency due to crossover of methanol from the anode to the cathode through the electrolyte membrane and the poisoning effect by carbon monoxide (CO). 6,7 After great efforts, researchers have been able to solve these challenges and found out that size controlled NPLs can be achieved in high yield using photo-induced, 4,6 seed-mediated, 8,9 “magic” reagent, 10 oxidative etching, 11,12 seed ratio 13 and reduction rate 14 techniques, as well as using the crystal symmetry of the starting nuclei. 15–17 To enhance the catalyst durability, designed catalysts should possess both good methanol tolerance and optimal activity for the oxygen reduction reaction (ORR).…”