The temperature stability and development of a broadband silver nanofluid for solar thermal applications

This paper details an investigation into the synthesis and temperature stability testing of silver-nanofluids, aimed at producing three silver-based nanofluids with distinctive morphologies absorption characteristics suitable for enhanced efficiency volumetric solar-thermal collectors, which could be combined a thermal storage system to provide low-carbon heating hot-water. When were designed give spectrally broadband incident solar radiation in 300–1300 nm range. The starting point was previously developed triangular silver-nanoparticles strong absorbance 850–950 range (Nanofluid 1). effect changing various reagents then investigated. Increasing silver nitrate concentration reducing agent ratio produced Nanofluid 2 (strong 650–750 range), containing smaller more rounded nanoparticles. For 3, two-step had adopted, seed nanofluid made initially by lowering (sodium borohydride) oxidizing (hydrogen peroxide). Additional added, giving concentrated nanofluid, small nanodiscs, 450 maximum. These together absorber first time, 70 °C measured using UV–vis–IR spectroscopy. Results indicate that although based on can it is not use without appropriate stabilization strategy, due lack spectral temperature.