• Energy Research

Abstract Gold nanoparticles (Au-NPs) seeded plasmonic nanofluids (PNFs) have shown promising results in overall performance enhancement of direct absorption solar collector (DASC) due to localized surface plasmon resonance (LSPR) effect. For the work presented here, Au-NPs were synthesized by the wet chemical method and were utilized to prepare plasmonic nanofluid. The surface plasmon resonance peak of Au-NPs was observed at 531 nm using UV–Visible spectrophotometer study. The testing for performance enhancement of gold plasmonic nanofluid (GPNF) laden DASC so far is limited to laboratory scale setups or simulation studies. Considering the dearth of outdoor experimental studies, an attempt has been made in the present study to evaluate the thermal performance of Au-NPs (∼40 nm) based nanofluid (∼0.0002 wt%) in full scale DASC. The experiments have been performed at different flow rates under clear sky outdoor conditions in winter season at Jalandhar, India. The maximum collector outlet temperature was measured to be 55 °C with GPNF which is about 7 °C higher than the maximum outlet temperature obtained with de-ionized water as working fluid. Thermal efficiency with GPNF is about 33% higher than de-ionized water at the optimal flow rate of 0.030 kg/s.

This article focuses on the plasmonic effect of gold nanoparticles incorporated in mesoporous TiO2 photoanode for high efficiency dye-sensitized solar cells (DSSC). We have adopted a facile TiCl4 posttreatment process for coating a thin TiO2 shell over the gold nanoparticles. The device without TiCl4 treatment and containing bare or uncoated gold nanoparticles exhibits a drop in efficiency compared to the control device. The cells fabricated with gold nanoparticles and posttreated with TiCl4 show higher efficiencies than the control device. The improvement in efficiency is attributed to a higher value of photocurrent in the plasmonic devices arising due to the near-field enhancement effects. The TiCl4 treated plasmonic cell provides a short-circuit current density ( J SC) of 12.90 mA/cm2 compared to 10.76 mA/cm2 obtained from the control device. The overall power conversion efficiency is enhanced from 4.81% for the control DSSC to 5.71% for the TiCl4 treated plasmonic DSSC. This plasmonic DSSC has also been compared with another type of plasmonic DSSC containing Au@SiO2 core-shell nanoparticles. The photovoltaic performances of the two types of plasmonic DSSCs utilizing dielectric shell coated Au NPs are found to be similar, indicating the suitability of the TiCl4 treatment for facile and reproducible fabrication of plasmonic solar cells.