Superhydrophobic Co-MOF-based sponge for efficient oil-water separation utilizing photothermal effect

Xuanting He; Jihan Lu; Jiaxiang Liu; Zixuan Wu; Boyu Li; Zhong Chen; Wenquan Tao; Zhuo Li

doi:10.1016/j.jhazmat.2024.134090

Superhydrophobic Co-MOF-based sponge for efficient oil-water separation utilizing photothermal effect

J Hazard Mater. 2024 May 5:469:134090. doi: 10.1016/j.jhazmat.2024.134090. Epub 2024 Mar 19.

Authors

Xuanting He¹, Jihan Lu¹, Jiaxiang Liu², Zixuan Wu¹, Boyu Li¹, Zhong Chen¹, Wenquan Tao¹, Zhuo Li³

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, 1239 Siping Road, Shanghai 200092, China.
² Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China.
³ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: zhuoli2013@tongji.edu.cn.

PMID: 38513439
DOI: 10.1016/j.jhazmat.2024.134090

Abstract

Effectively addressing crude oil spills remains a global challenge due to its high viscosity and limited flow characteristics. In this study, we successfully prepared a modified sponge (PCP@MS) by embedding the photothermal material of Co-HHTP and coating the melamine sponge (MS) with low-surface-energy polydimethylsiloxane (PDMS). The PCP@MS exhibited outstanding hydrophobicity with WCA of 160.2° and high oil absorption capacity of 59-107 g/g. The PCP@MS showed high separation efficiency of 99.2% for various oil-water mixtures, along with notable self-cleaning properties and mechanical stability. The internal micro-nano hierarchical structure on the sponge surface significantly enhanced light absorption, synergizing with the photo-thermal conversion properties of Co-HHTP, enabled PCP@MS to achieve a surface temperature of 109.2 °C under 1.0 solar light within 300 s. With the aid of solar radiation, PCP@MS is able to heat up quickly and successfully lowering the viscosity of the surrounding crude oil, resulting in an oil recovery rate of 8.76 g/min. Density functional theory (DFT) calculation results revealed that Co-HHTP featured a zero-gap band structure, rendering advantageous electronic properties for full-wavelength light absorption. This in situ solar-heated absorbent design is poised to advance the practical application of viscous oil spill cleanup and recovery.

Keywords: Crude oil recovery; Melamine sponge; Oil-water separation; Photothermal materials.