The control of heat at the nanoscale via the excitation of localized surface plasmons in nanoparticles (NPs) irradiated with light holds great potential in several fields (cancer therapy, catalysis, desalination). To date, most thermoplasmonic applications are based on Ag and Au NPs, whose cost of raw materials inevitably limits the scalability for industrial applications requiring large amounts of photothermal NPs, as in the case of desalination plants. On the other hand, alternative nanomaterials proposed so far exhibit severe restrictions associated with the insufficient photothermal efficacy in the visible, the poor chemical stability, and the challenging scalability. Here, it is demonstrated the outstanding potential of NiSe and CoSe topological nodal‐line semimetals for thermoplasmonics. The anisotropic dielectric properties of NiSe and CoSe activate additional plasmonic resonances. Specifically, NiSe and CoSe NPs support multiple localized surface plasmons in the optical range, resulting in a broadband matching with sunlight radiation spectrum. Finally, it is validated the proposed NiSe and CoSe‐based thermoplasmonic platform by implementing solar‐driven membrane distillation by adopting NiSe and CoSe nanofillers embedded in a polymeric membrane for seawater desalination. Remarkably, replacing Ag with NiSe and CoSe for solar membrane distillation increases the transmembrane flux by 330% and 690%, respectively. Correspondingly, costs of raw materials are also reduced by 24 and 11 times, respectively. The results pave the way for the advent of NiSe and CoSe for efficient and sustainable thermoplasmonics and related applications exploiting sunlight within the paradigm of the circular blue economy.

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The recent advent of two-dimensional (2D) materials has had a ground-breaking impact on science and technology. To exploit in technology their unique thickness-dependent physicochemical properties, the large-scale production of 2D materials is mandatory, but it represents an open challenge still due to various pitfalls and severe limitations including the toxicity of state-of-the-art solvents. Thus, liquid-phase exfoliation based on green and bioderived solvents represents an ideal methodology for massive production. This is particularly crucial for introducing 2D materials in technological applications such as the production of drinking water and agri-food industrial processes. Here, we assessed the production of 2D nanosheets (specifically, graphene, WS2, MoS2) with liquid-phase exfoliation assisted by eco-friendly solvents, with a comparative evaluation of green solvents in terms of the yield and, moreover, the aspect ratio, defectivity, and crystalline quality of the produced nanosheets. In particular, we focus on the most promising green solvents in terms of the yield and the crystalline quality of the produced nanosheets: Polarclean, Iris, and Cyrene, which were compared with acetone/water mixtures, isopropyl alcohol (IPA), triethanolamine (TEA), aqueous solutions of urea, and an ethanol/water mixture as well as two toxic solvents largely used for the production of 2D nanosheets: N-methyl-2-pyrrolidone (NMP) and N, N-dimethylformamide (DMF). Remarkably, the density of defects was particularly low in the liquid-phase exfoliation with Polarclean, as indicated by the Raman spectrum of graphene, with the I(D)/I(G) ratio below 0.1. Furthermore, Polarclean and Iris also enable ink-jet printing with functional inks of 2D materials based on green solvents due to their low dynamic viscosity at room temperature.

Liquid‐phase exfoliation of bulk crystals of layered materials, held together by weak interlayer van der Waals forces, is an ideal platform for scalable synthesis of nanosheets. However, it is mandatory to substitute existing solvents, regrettably displaying severe limitations due to toxicity. Here, dimethyl 2‐methylglutarate (Rhodiasolv Iris) is validated for efficient liquid‐phase exfoliation of selected van der Waals materials, namely, MoS2, WS2, GeSe, and graphite. Here, we show that Iris‐assisted liquid phase exfoliation provides high yield (up to 52%) of flakes of 2D materials with aspect ratio as high as 500. Considering the various advantages of Iris over the state‐of‐the‐art solvents, including the absence of toxicity and its biodegradability, this work opens new possibilities for the ecofriendly production of 2D materials and for their extensive usage in industrial processes hitherto semi‐unexplored, owing to the toxicity of state‐of‐the‐art solvents (including the production of drinkable water or fruit juice concentration). Accordingly, the validation of Iris for sustainable liquid‐phase exfoliation of van der Waals crystals has intrinsic outstanding potential commercial impact. Moreover, here the values of the surface tension, Hansen solubility parameter, and viscosity of Rhodiasolv Iris are reported for the first time, which will be relevant also for any other sustainable process based on this new green solvent.