Silica-nanoparticle reinforced lubricant-infused copper substrates with enhanced lubricant retention for maintenance-free heat exchangers

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-01, Vol.451, p.138657, Article 138657
• Main Authors: Ryu, Min, Choi, Hyoungwoo, Yoon, Jongsun, Choi, Yun-Nam, Lee, Sukyoung, Kim, Hyeongjeong, Chae, Minji, Lee, Jeong Wook, Kang, Jinkyu, Lee, Hyomin
• Format: Article
• Language: English
• Subjects: Acid resistance; Copper; Heat exchanger; Liquid-infused surface; Wetting
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2022.138657

•Silica nanoparticles are assembled for enhanced durability and acid-resistance.•Fluorocarbon oil is used as the lubricant for self-cleaning of contaminants.•Enhanced lubricant retention is verified through force tensiometry. 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.