Thanks to their record high refractive index and giant optical anisotropy, van der Waals (vdW) materials have accelerated the development of nanophotonics. However, traditional high refractive index materials, such as titanium dioxide (TiO₂), still dominate in the most important visible range. This is due to the current lack of transparent vdW materials across the entire visible spectrum. In this context, we propose that germanium disulfide (GeS₂) could offer a significant breakthrough. With its high refractive index, negligible losses, and biaxial optical anisotropy across the whole visible range, GeS₂ has the potential to complement TiO₂ and close the application gap of vdW materials in the visible spectrum. The addition of GeS₂ could have a profound impact on the design of van der Waals nanophotonic circuits for any operation wavelength from ultraviolet to infrared, emphasizing the significance of the potential impact of GeS₂ on the field of nanophotonics.

Transition metal dichalcogenides (TMDCs), particularly molybdenum disulfide (MoS₂), have gained significant attention in the field of optoelectronics and photonics due to their unique electronic and optical properties. The integration of TMDCs with plasmonic materials allows to tailor the optical response and offers significant advantages for photonic applications. This study presents a novel approach to synthesize MoS₂-Au nanocomposites utilizing femtosecond laser ablation in liquid to achieve tunable optical properties in the near-infrared (NIR) region. By adjusting ablation and fragmentation protocols, we successfully synthesize various core–shell and core–shell–satellite nanoparticle composites, such as MoS₂/MoS_xO_y, MoS_xO_y/Au, and MoS₂/MoS_xO_y/Au. UV-visible absorption spectroscopy unveils considerable changes in the optical response of the particles depending on the fabrication regime due to structural modifications. Hybrid nanoparticles exhibit enhanced photothermal properties when subjected to NIR-I laser irradiation, demonstrating potential benefits for selective photothermal therapy. Our findings underscore that the engineered nanocomposites not only facilitate green synthesis but also pave the way for tailored therapeutic applications, highlighting their role as promising candidates in the field of nanophotonics and cancer treatment.

The formation of polyene-polyyne-based nanocomposites by dehydrohalogenation of the drop-cast-deposited polyvinylidene fluoride, assessment and ion-induced tailoring of their gas sensing properties are reported. The investigated structure was analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy, transmission electron microscopy and Fourier-transform infrared spectroscopy, revealing the thickness-dependent incomplete dehydrofluorination of the structure and its porosity induced by KOH treatment. The polyene-polyyne structures modified by low-energy Ar⁺ were studied by SEM and Raman spectroscopy, which showed the morphology variation, the shortening of chains and the graphitization of samples. The resistive gas sensing properties of the samples were analyzed at room temperature, revealing selective sensing of ammonia vapor by non-irradiated sample and the enhancement of the sensing properties for ethanol and water vapor after ion irradiation. With the ion dose enlargement, the change in the sensing response from electrical conductivity increase to decrease was observed for ammonia and ethanol, allowing us to discuss the origin and tunability of the sensing mechanism of the samples.