Synthesis of gold nanorods with a longitudinal surface plasmon resonance peak of around 1250 nm

Thi Nhat Hang Nguyen, Thi Le Trinh Nguyen, Thi Thanh Tuyen Luong, Canh Minh Thang Nguyen and Thi Phuong Phong Nguyen

Abstract

We prepared gold nanorods and joined them to chemicals such as tetrachloauric (III) acid trihydrate, silver nitrate, hydroquinone, hexadecyltrimethylammonium bromide, sodium hydroxide and sodium borohydride using the seed-mediated method. The combination of hydroquinone, with or without salicylic acid, influences the size of the gold nanorods, and this is demonstrated by the results of TEM images, UV–vis spectra and the value of the longitudinal surface plasmon resonance peak with respect to the UV–vis spectra. By changing the Ag⁺ ion and hydroquinone concentration and the combination of hydroquinone and salicylic acid, the size of the gold nanorods can be controlled and this is manifested by longitudinal surface plasmon resonance peaks forming between 875 and 1278 nm. In particular, sample E2 achieved a  longitudinal surface plasmon peak at 1273 nm and an aspect ratio of more than 10 by modifying the hydroquinone to 2.5 mM and salicylic acid to 0.5 mM concentration in the growth solution