Ahmad Wani Tawseef, Garg Parul, Bera Saheb, Bhattacharya Sanchari, Dutta Sanjoy, Kumar Hemant, Bera Ashok
Department of Physics, Indian Institute of Technology Jammu, Jammu and Kashmir 181221, India.
School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Odisha 752050, India.
J Colloid Interface Sci. 2022 Apr 15;612:203-212. doi: 10.1016/j.jcis.2021.12.158. Epub 2021 Dec 29.
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 LaMO (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 LaNiO and semiconducting LaCoO 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 LaNiO absorber, we achieved an evaporation rate of 2.3 kg m h, 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.
光热水蒸发为解决全球淡水短缺问题提供了一条充满前景的途径。在材料中沿不同方向实现功能的协同整合是设计多功能材料的关键策略。镧基钙钛矿复合氧化物LaMO（M = Ni和Co）具有窄带隙和高吸收系数。这些功能尚未在光热能量转换方面得到充分探索。在此，我们合成了纳米结构的金属LaNiO和半导体LaCoO，并将它们用于设计界面太阳能蒸汽发生器。这些材料在整个太阳光谱范围内具有有效的光吸收能力，两种材料的光热效率均达到83%左右。使用带有LaNiO吸收器的锥形三维界面蒸汽发生器，我们实现了2.3 kg m⁻² h⁻¹的蒸发速率，对应的太阳能蒸汽产生效率超过95%。据我们所知，该蒸发速率高于迄今为止报道的任何基于氧化物的界面太阳能蒸汽发生器。此外，我们还展示了一种使用此类蒸发器进行长期海水淡化的有效方法。
