Narrow-Bandgap LaMO3 (M = Ni, Co) nanomaterials for efficient interfacial solar steam generation

Tawseef Ahmad Wani; Parul Garg; Saheb Bera; Sanchari Bhattacharya; Sanjoy Dutta; Hemant Kumar; Ashok Bera

doi:10.1016/j.jcis.2021.12.158

Narrow-Bandgap LaMO₃ (M = Ni, Co) nanomaterials for efficient interfacial solar steam generation

J Colloid Interface Sci. 2022 Apr 15:612:203-212. doi: 10.1016/j.jcis.2021.12.158. Epub 2021 Dec 29.

Authors

Tawseef Ahmad Wani¹, Parul Garg¹, Saheb Bera², Sanchari Bhattacharya³, Sanjoy Dutta³, Hemant Kumar², Ashok Bera⁴

Affiliations

¹ Department of Physics, Indian Institute of Technology Jammu, Jammu and Kashmir 181221, India.
² School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Odisha 752050, India.
³ Department of Physics and Astronomy, National Institute of Technology Rourkela, Odisha 769008, India.
⁴ Department of Physics, Indian Institute of Technology Jammu, Jammu and Kashmir 181221, India. Electronic address: ashok.bera@iitjammu.ac.in.

PMID: 34992020
DOI: 10.1016/j.jcis.2021.12.158

Abstract

Photothermal water evaporation provides a pathway towards a promising solution to global freshwater scarcity. Synergistic integration of functions in a material in diverse directions is a key strategy for designing multifunctional materials. Lanthanum-based perovskite complex oxides LaMO₃ (M = Ni and Co) have narrow band gaps with a high absorption coefficient. These functionalities have not been appropriately explored for photothermal energy conversion. Here, we synthesized nanostructured metallic LaNiO₃ and semiconducting LaCoO₃ and used them to design interfacial solar steam generators. Effective light absorption capability over the entire solar spectrum of these materials leads to a photothermal efficiency of the order of 83% for both materials. Using a cone-shaped 3D interfacial steam generator with a LaNiO₃ absorber, we achieved an evaporation rate of 2.3 kg m^-2 h^-1, corresponding to solar vapor generation efficiency of over 95%. To the best of our knowledge, this evaporation rate is higher than any oxide-based interfacial solar steam generator reported so far. Furthermore, we have also shown an effective way of using such evaporators for long-term seawater desalination.

Keywords: Desalination; High absorbance; Interfacial solar steam generation; LaCoO(3), LaNiO(3); Nanomaterials; Narrow bandgap.