Agglomeration of Nanoparticles in Organic Phase-Change Materials for PV/T Systems: Causes, Effects, and Mitigation

Abstract

Nanoparticle-enhanced phase-change materials (NePCMs) have been widely explored to improve thermal management in photovoltaic/thermal (PV/T) systems by raising PCM thermal conductivity. However, nanoparticles tend to cluster or settle out over time (agglomeration), degrading performance and stability. This review examines how and why nanoparticles agglomerate in organic PCMs used with PV/T, the consequences for thermal and PV/T performance, and methods to prevent or mitigate agglomeration. We summarize mechanisms of nanoparticle clustering (e.g. surface forces and poor dispersion), document impacts on heat storage capacity and system efficiency, and outline experimental strategies (surfactants, sonication, functionalization, etc.) shown to enhance NePCM stability. A comprehensive literature survey highlights recent studies on organic NePCMs in PV/T and reveals remaining challenges (e.g. long-term reliability and optimal formulations) and future research directions. By integrating findings from 31 sources, this article provides an in-depth resource on nanoparticle gglomeration in organic PCMs for PV/T applications.