Emergence of the Janus-MOF (J-MOF) Boat as a Nascent Amalgamation in the Arena of Photothermal Desalination

Abhyavartin Selvam; Yashtika Raj Singh; Amarnath Karna; Amit Bhatnagar; Monalisa Mukherjee; Sandip Chakrabarti

doi:10.1021/acsami.3c05187

Emergence of the Janus-MOF (J-MOF) Boat as a Nascent Amalgamation in the Arena of Photothermal Desalination

ACS Appl Mater Interfaces. 2023 Jun 7;15(22):26918-26927. doi: 10.1021/acsami.3c05187. Epub 2023 May 23.

Authors

Abhyavartin Selvam¹, Yashtika Raj Singh¹, Amarnath Karna², Amit Bhatnagar³, Monalisa Mukherjee⁴, Sandip Chakrabarti¹

Affiliations

¹ Amity Institute of Nanotechnology, Amity University, Noida, Uttar Pradesh 201313, India.
² Amity Institute of Molecular Medicine and Stem Cell Research, Amity University, Noida, Uttar Pradesh 201313, India.
³ Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, Mikkeli FI-50130, Finland.
⁴ Amity Institute of Click Chemistry Research and Studies, Amity University, Noida, Uttar Pradesh 201313, India.

PMID: 37218516
DOI: 10.1021/acsami.3c05187

Abstract

The diminution of potable water is a pressing issue in several countries and is the most prioritized obligation of environmental scientists. Thence, the ardent emergence of photothermal interfacial evaporation (PTIE) is seen as a neoteric horizon in the avenue of water remediation. Consequently, for the first time, the decoration of metal-organic frameworks (MOFs) over a Janus architecture as an avant-garde marriage was explored in the domain of photothermal desalination. In this study, a solar absorber was developed by inducing phase change to Ni-doped HKUST-1 (Cu-MOF) via high-temperature calcination to create biphasic CuO/Cu₂O caged in N-doped graphene oxide (NGO) sheets. The doping of Ni in the framework demonstrated to enhance the pyrrolic nitrogen (P_N) of NGO sheets, which improved the photothermal feature of the solar absorber in union with promoting Cu²⁺ species as well as enriching the p-type nature of the biphasic configuration for augmented nonradiative relaxation of electrons. In order to take advantage of the robust potential of the designed solar absorber, it was coated over a Janus membrane prepared via the facile approach, composed of poly(methyl methacrylate) (PMMA) and agarose gel having opposing wettability, referred to as the J-MOF boat. This nascent amalgamation recorded a maximum evaporation rate of 1.5 kg/m² h with pure water and 1.3 kg/m² h with simulated seawater under 1 sun irradiation. This phenomenon was ascribed to the highly porous agarose layer to facilitate extraordinary water pumping, while concomitantly rejecting salts via capillary action in a nature-mimicking fashion as seen in mangrove trees. The boat-like feature arises from the PMMA layer to conduct PTIE at the water/air interface by uniformly dispersing the localized heat from the solar absorber owing to its low thermal conductivity and three-dimensional (3D) porous structure. Thus, it is believed that this nascent strategy could push the boundaries of solar-driven desalination.

Keywords: Janus membrane; interfacial evaporation; metal−organic frameworks; photothermal desalination; solar absorber.