Spectrum and size controllable synthesis of high-quality gold nanorods using 1,7-dihydroxynaphthalene as a reducing agent

Abstract

The spectrum and size controlled synthesis of gold nanorod is of great value for its widely applicable aspect ratio-dependence property of anisotropic surface plasmon resonance. Herein, 1,7-dihydroxynaphthalene with a relatively...

Controlled synthesis of monodisperse gold nanorods with a small diameter of around 10 nm and largest plasmon wavelength of 1200 nm

“…46 At the same time, the AuNR acquired from this method also shows high levels of shape yield and monodispersity. 46 As a brief summary, these research studies indicated that facile acquisition of AuNRs with a simultaneously guaranteed LSPR wavelength of beyond 1000 nm, a small diameter, and a high shape yield and monodispersity is still a great challenge. Nevertheless, it can also be inferred that the specific function pathway of different reducing agents is not fully revealed and more study is deserved.…”

“…Similar to many previously reported works, these results clearly reveal that firstly the increase of CTAB could facilitate the anisotropic growth of the particle that causes a decreased shape impurities and an increased rod' aspect ratio, which contributes the reagent an effect analogue to that of the silver ion. 28,30,32,46 Second, it has been discussed in the literature and our recent work that the function of CTAB in the particle anisotropic growth is based on its combination with silver ions that could significantly affect the Ag-UPD effect, of which a stronger side wall growth confinement of AuNR at a lower concentration of CTAB could result in a smaller diameter of the rod formed, and vice versa. 46,48,59 From this perspective, the slightly increased change in rod's diameter with the increment in CTAB that is opposite to that of silver ions showing a decreased change should exactly be the consequence of this mechanism.…”

“…28,30,32,46 Second, it has been discussed in the literature and our recent work that the function of CTAB in the particle anisotropic growth is based on its combination with silver ions that could significantly affect the Ag-UPD effect, of which a stronger side wall growth confinement of AuNR at a lower concentration of CTAB could result in a smaller diameter of the rod formed, and vice versa. 46,48,59 From this perspective, the slightly increased change in rod's diameter with the increment in CTAB that is opposite to that of silver ions showing a decreased change should exactly be the consequence of this mechanism. What is more, after the increase in CTAB reaches the maximum concentration (0.1 M) that is needed for the synergy with silver ions on particle prolongation, severe growth restriction can occur at the ends of AuNRs, so that a few of AuNRs display a remarkably decreased length prolongation but a distinctive diameter increment, causing a blue-shift and a broadening of the LSPR peak (Fig.…”

“…Very recently, our group also reported an improved AuNR synthetic method using 1,7-dihydroxynaphthalene as a reducing agent. 46 Although the AuNR prepared by this method only shows the largest LSPR wavelength of around 1000 nm and a diameter of 14.3 nm, fine tuning of these parameters can be acquired by varying the amount of reducing agents or gold seeds, in which a LSPR control range of 1000-800 nm and a smallest diameter of around 7.3 nm are shown, offering a new insight of view in spectral and size controls of AuNRs. 46 At the same time, the AuNR acquired from this method also shows high levels of shape yield and monodispersity.…”

“…46 Although the AuNR prepared by this method only shows the largest LSPR wavelength of around 1000 nm and a diameter of 14.3 nm, fine tuning of these parameters can be acquired by varying the amount of reducing agents or gold seeds, in which a LSPR control range of 1000-800 nm and a smallest diameter of around 7.3 nm are shown, offering a new insight of view in spectral and size controls of AuNRs. 46 At the same time, the AuNR acquired from this method also shows high levels of shape yield and monodispersity. 46 As a brief summary, these research studies indicated that facile acquisition of AuNRs with a simultaneously guaranteed LSPR wavelength of beyond 1000 nm, a small diameter, and a high shape yield and monodispersity is still a great challenge.…”