# Electronic and Optical Behaviors of Platinum (Pt) Nanoparticles and Correlations with Gamma Radiation Dose and Precursor Concentration

## TL;DR

This study explores how gamma radiation and precursor concentration affect the size and optical properties of platinum nanoparticles.

## Contribution

The research establishes a direct correlation between gamma radiation dose, precursor concentration, and the electronic/optical properties of Pt nanoparticles.

## Key findings

- Higher gamma radiation doses produce smaller Pt nanoparticles due to increased nucleation.
- Higher precursor concentrations result in larger nanoparticles due to increased ion recombination.
- Optical absorption and conduction band energy show quantum confinement effects linked to nanoparticle size.

## Abstract

The purpose of this research is to examine how the electro-optical behavior of platinum (Pt) nanoparticles prepared via the gamma radiolysis process is related to both the radiation dose and to the Pt precursor concentration. The Pt precursor used in these experiments has been radiolytically degraded using a 60Co gamma source at dosages ranging from 80 kGy to 120 kGy. As well, varying the concentration of the Pt precursor from 5.0 × 10−4 M to 20.0 × 10−4 M was carried out as a systematic investigation. Spectrophotometric analysis utilizing UV–Visible spectroscopy and TEM provided the optical data and particle size information for the nanoparticles. The results indicate that increasing the radiation dosage results in smaller Pt nanoparticle sizes due to an increased rate of nucleation and that increasing the Pt precursor concentration leads to larger Pt nanoparticles due to an increase in ion recombination. Both the dose and concentration dependency of the optical absorption spectrum indicate a significant relationship between size and plasmon behavior. Also, the conduction band energy level, which was determined from the maximum of the UV–Visible absorption peak, is dependent on the particle size and shows a pronounced quantum confinement effect, with the conduction band energy increasing as the particle size decreases. Thus, these studies provide a definitive correlation of structure–property in Pt nanoparticles and confirm the capability of the gamma radiolytic synthesis process to be used for controlling the specific electronic and optical properties of Pt nanoparticles.