In-situ deposition of gold nanoparticles onto different substrates by chemical spray pyrolysis

Abstract

Abstract. Au-nanoparticles were deposited in-situ by chemical spray pyrolysis method onto glass and indium tin oxide (ITO) covered glass substrates in the temperature range of 260 to 400 °C. SEM studies showed that the number of Au-NPs increased and the particle size decreased with increasing the deposition temperature. The surface plasmon resonance effect of Au-NPs on glass substrate shifts from 550 to 520 nm with decreasing the mean crystallite size of Au-NPs from 49 to 24 nm. The surface plasmon resonance effect of Au-NPs on ITO substrate shift from 570 to 540 nm with decreasing the mean crystallite size of Au-NPs from 53 to 16 nm. IntroductionNoble metal nanoparticles (NPs) such as gold, silver and copper have attracted researchers' interest due to their unique plasmonic properties and potential applications in optics, nanoelectronics, biomedicine, catalysis and photovoltaics [1][2][3][4]. Spectral position of plasmon resonance depends on the size and shape of nanoparticles, distance between them and permittivity of environment and metal [5]. Metal nanoparticles have been deposited by several methods such as electrodeposition [6], sputtering [7], spin-coating [8,9] and spray pyrolysis [10][11][12].Chemical spray pyrolysis (CSP) is a low-cost material deposition method; here the solution of appropriate precursor materials is deposited in the form of fine droplets onto the preheated substrate where the growth of material takes place. To obtain Au-NPs by spray pyrolysis either preformed nanoparticles are sprayed [13] or Au-NPs are generated via thermal decomposition of Au-precursor salts such as HAuCl4•nH2O, HAuCl4,14,15]. The previous thermoanalytical study has shown that the thermal decomposition of HAuCl4•3H2O into pure gold and gaseous products takes place as a gradual decomposition process in the temperature range of 75-320 °C in air. Despite that, Au and AuCl were detected as the intermediate decomposition products at 240 °C [16].Au-NPs deposited in-situ by chemical spray pyrolysis method have been grown directly onto glass and ITO (indium tin oxide) covered glass substrates by ultrasonic spray pyrolysis [11,12] or deposited in combination with several metal oxide [11,12,14,15] and sulfides [10] matrixes. Moreover, it has been shown lately, that Au-NPs deposited in-situ by chemical spray pyrolysis method have enhanced the out-put characteristics of the solely sprayed thin film solar cell [17].

Self-organization of gold nanoparticles on silanated surfaces

“…Different techniques have been used to assemble AuNPs on various surfaces in which the stability of AuNPs, interface layer and the support surface are important for the self-organization. Han et al have demonstrated the growth of a single layer AuNPs film deposited on indium tin oxide (ITO) substrate without using an adhesive layer by utilizing diblock copolymer micelle and spin casting technique [18], while Acik et al reported in situ deposition of AuNPs on ITO and glass substrate by using spray pyrolysis (temperature range of 260–400 °C) [19]. Wu et al proposed AuNPs deposition by centrifugation where the thickness depended on centrifugation time [20].…”