[Abstract]

Copper substrates are widely used in heat exchangers due to their low cost and high thermal conductivity. While copper substrates have been modified to exhibit non-wetting property via lubricant infusion to enhance condensation heat transfer efficiency, these engineered surfaces often lack chemical robustness and lubricant retention, limiting their long-term use without maintenance. In this work, we present a new strategy in which omniphobic and chemically inert fluorocarbon oil is infused into a nanostructured copper substrate reinforced with silica nanoparticles (SiNP) to achieve enhanced durability and acid-resistive properties. We demonstrate that the assembly of SiNP layer prior to lubricant infusion serves as a physical barrier and provides additional anchoring points for the lubricant to retain via capillary force. Moreover, we show that SiNP-reinforced liquid-infused surface (LIS) exhibits excellent non-wetting and self-cleaning properties, leading to enhanced stability against acid exposure as well as dust, oil, and microbial contamination. Based on the excellent long-term stability in heat transfer performance even under harsh environmental challenges, we envision that the SiNP-reinforced LIS presented in this work will provide new insight in the design of robust and maintenance-free lubricant-infused surfaces for energy and environmental applications.

DOI : https://doi.org/10.1016/j.cej.2022.138657

Link : https://www.sciencedirect.com/science/article/pii/S1385894722041389