Gold nanoparticles (AuNPs) have been extensively utilized in various

fields such as sensors, life sciences, and catalysis. In this study,

AuNPs were synthesized using a reduction method and subsequently treated

with thiourea in an ethanol-water environment to prepare AuNPs film

using a centrifugal deposition method for first time, resulting in the

aggregation of the initial small-sized AuNPs into larger

microsphere-like structures. The addition of thiourea facilitated the

interconnection between AuNPs, ultimately leading to the formation of

large stable gold microspheres. The sheet resistance of the AuNP films

transitioned from being non-conductive to exhibiting a sheet resistance

of 42.6 Ω/sq following thiourea treatment. The transformation from a

flat surface to tightly connected particles resembling microspheres was

observed from SEM images. The thiourea treatment not only altered the

morphological characteristic of the AuNPs films but also significantly

increased the number of scattering sites on their surface, leading to a

substantial enhancement in the Raman scattering effect for methylene

blue. This structural configuration also improved the electronic

conduction and stability of the treated AuNPs films. Consequently, these

findings suggest that AuNPs have promising application prospects in

surface-enhanced Raman scatting (SERS), as well as in flexible

electronics, catalysis, adsorption, and energy fields.