Microlandscaping on a graphene oxide film via localized decoration of Ag nanoparticles

Abstract

A direct and facile method for micro-landscaping of Ag nanoparticles on reduced graphene oxide (rGO) is presented. This method employs a focused laser beam to achieve local reduction of Ag(+) ions to Ag NPs by laser irradiation on a GO film that is submerged in AgNO3 solution. Using this method, the Ag nanoparticles can be directly anchored on a rGO film, creating a microlandscape of Ag nanoparticles on the rGO film. In addition, varying the intensity of the laser beam can control the shapes, sizes and distributions of Ag nanoparticles. The resulting hybrid materials exhibit surface enhanced Raman scattering of up to 16 times depending on the size and number density of silver nanoparticles. In addition, the hybrid Ag-rGO material shows superior photoresponse when compared to rGO.

Recent Advances in Laser Utilization in the Chemical Modification of Graphene Oxide and Its Applications

“…A direct and facile method for the microdecoration of AgNPs on the reduced rGO can be achieved employing a focused laser beam to cause the local reduction of Ag + ions to AgNPs (Equations ( 12) , ( 13) , ( 14) , ( 15) ) by the laser irradiation of a GO fi lm submerged in an aqueous AgNO 3 solution. Teoh and colleagues [ 84 ] suggested a mechanism for such a local reduction. Firstly, laser irradiation produces electrons and holes: the electrons are used for the reduction of Ag + or GO (Equations ( 14) , ( 15) ), while the holes cause oxygen evolution from water (Equation ( 13) ): [ 84 ] …”

“…Teoh and colleagues [ 84 ] suggested a mechanism for such a local reduction. Firstly, laser irradiation produces electrons and holes: the electrons are used for the reduction of Ag + or GO (Equations ( 14) , ( 15) ), while the holes cause oxygen evolution from water (Equation ( 13) ): [ 84 ] …”

“…[ 84,85 ] In such a way, the NPs are directly anchored on the rGO fi lm, creating a microlandscape, as presented in Figure 14 . [ 84 ] In addition, by varying the intensity of the laser beam, the shape, size, and distribution of NPs can be controlled: a higher intensity leads to larger NPs at a lower concentration.…”

“…[ 84,85 ] In such a way, the NPs are directly anchored on the rGO fi lm, creating a microlandscape, as presented in Figure 14 . [ 84 ] In addition, by varying the intensity of the laser beam, the shape, size, and distribution of NPs can be controlled: a higher intensity leads to larger NPs at a lower concentration. Interestingly, the size strongly depends on the laser beam intensity, but it is independent of the precursor concentration in the range between 0.01 and 0.1 M. The resulting hybrid materials exhibit surface-enhanced Raman scattering up to 16 times higher than that of GO, depending on the size and density of AuNPs.…”

Deposition of Copper Nanoparticles on 2D Graphene NanoPlatelets via Cementation Process

“…Teoh et al have taken advantage of this method by using a focused laser beam to reduce Ag ions into Ag NPs on a GO film that was submerged in AgNO3 solution, resulting in Ag NPs attached to the GO surface [58].…”