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Siloxane-oxide hybrid coatings have been prepared via the hydrolysis-condensation of diethoxydimethylsilane and various metallic alkoxides, M(OR), with M=Si, Ti, Zr and Al. The rheological behaviour of the precursor sols and their hydrophobic character due to the presence of methyl groups, allows the formation of films several tens of micrometres thick, with no cracks. Preliminary structural characterizations are presented on the Ticontaining system using MAS NMR and X-ray absorption techniques. Rhodamine 6G and coumarin 4 have been embedded in these films. Some preliminary optical properties (absorption and emission) are presented. Most of the systems exhibit strong fluorescence, even for high dye concentration. This effect seems to be related to the particular structural nature of these matrices.

Photodetectors based on transition metal dichalcogenides (TMDs) have been widely reported in the literature and molybdenum disulfide (MoS2) has been the most extensively explored for photodetection applications. The properties of MoS2, such as direct band gap transition in low dimensional structures, strong light–matter interaction and good carrier mobility, combined with the possibility of fabricating thin MoS2 films, have attracted interest for this material in the field of optoelectronics. In this work, MoS2-based photodetectors are reviewed in terms of their main performance metrics, namely responsivity, detectivity, response time and dark current. Although neat MoS2-based detectors already show remarkable characteristics in the visible spectral range, MoS2 can be advantageously coupled with other materials to further improve the detector performance Nanoparticles (NPs) and quantum dots (QDs) have been exploited in combination with MoS2 to boost the response of the devices in the near ultraviolet (NUV) and infrared (IR) spectral range. Moreover, heterostructures with different materials (e.g., other TMDs, Graphene) can speed up the response of the photodetectors through the creation of built-in electric fields and the faster transport of charge carriers. Finally, in order to enhance the stability of the devices, perovskites have been exploited both as passivation layers and as electron reservoirs.

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