Analyzing the thermal potential of binary 2D (h-BN/Gr) nanoparticles enhanced lauric acid phase change material for photovoltaic thermal system application

Abstract

Thermal energy storage as latent heat is an effective strategy to preserve the excessive energy available. In this aspect, fatty acid phase change materials (PCMs) are promising materials since they have a high latent heat, nontoxic, and little sub-cooling. However, their inherently low thermal conductivity severely restricts their applicability. Herein, hexagonal boron nitride (h-BN) and graphene (Gr) binary nanoparticles (NPs) are taken as nano-additives to enhance thermal conductivity of lauric acid (LA). The NPs added PCM known as nano-enhanced phase change material (NePCM) is prepared by two-step method for thermo-physical characterization. According to an optical performance investigation using ultraviolet-visible spectroscopy (UV–Vis); optimal composite LBG2% (LA with 3 % h-BN and 2 % Gr NPs) displayed 78 % reduction in transmissibility compared to base LA. Further, LBG2% composites exhibited elevated thermal conductivity of LA by 97 %. Additionally, differential scanning calorimeter (DSC) observed a slight variation in latent heat and melting temperature. Latent heat for composite LBG2% found to be as 176 Jg−1 with a reduction equal to NPs weight% as compared to base LA. Moreover, the preferred composite LBG2% displays chemical stability and thermal reliability after 500 heating/cooling cycles. The addition of LBG2% NePCM to a photovoltaic thermal system increased electrical and thermal efficiency to 9.41 % and 69 %, respectively, as compared to the photovoltaic thermal system alone, which was 7.1 % and 64 %. It can be concluded, the binary NPs enhanced composite LBG2% exhibited improved photoabsoprtion and thermal conductivity, along with thermal reliability and higher latent heat. The composite has significant application potential within the melting temperature range of 50 °C for employment in solar photovoltaic systems and other applications.