Platinum and palladium nanoparticles doped photopolymer for reflection holography

Volume holographic reflection grating storage in eco-friendly photopolymers is a current challenge. Besides, they have the potential for usage in important applications such as sensors and holographic optical elements. The main objective of this work was the modification of the composition of Biophotopol, a low toxicity photopolymer based on poly(vinyl alcohol), in order to increase the diffraction efficiency of the reflection gratings. For it, high refractive index Platinum and Palladium nanoparticles were then added to the holographic material to improve refractive index modulation during the recording phase. The concentration of nanoparticles employed was taken into consideration. Using a concentration of 0.58 nanomoles of Platinum nanoparticles per gram of poly(vinyl alcohol), maximum diffraction efficiency above 50% was achieved. These were, to the best of our knowledge, the best results so far obtained for high-frequency holographic reflection gratings in a low-toxicity material.