Human safety and the protection of air quality would clearly benefit from the deployment of widespread, unattended, wireless networks with gas sensing capabilities. While the Internet of Things (IoT) is on the rise (3.2 billion devices connected by 2023), the 5G will improve IoT performance and reliability. The development of high frequency field effect transistors (HF-FETs) for wireless networks is fuelling the research in a new generation of high frequency electronics employing new nanomaterials. In this context, the HF2ET2D aims at the synthesis of two-dimensional (2D) materials and at the fabrication of HF-FETs in order to realize high frequency gas sensors for being integrated in the new generation of unattended gas sensor networks. Additionally, it aims at improving sensor performance (sensitivity and selectivity) by using surface functionalization and light excitation. 2D materials like black phosphorus, Indium Selenium (InSe) and Platinum Diselenide (PtSe2) are still very new materials, which deserve being investigated further. Their rich electrical-optical-gas sensing properties will allow us to fabricate high frequency FET gas sensors with superior performance. The crystalline quality of these materials, their good carrier mobility and high on/off current will affect the figure of merit of the HF-FETs (maximum frequency of oscillation and the cut-off frequency). Direct band gap, good light absorbance, and high photo-responsivity are interesting factors to enhance the electrical characteristics of the transistors and ameliorate the repeatability and drift issues often experienced with gas sensors. Ultra large surface to volume ratios, rich surface chemistry and favourable surface energy levels for gas adsorption will allow to obtain room temperature gas sensors and avoid the high operation temperature of commercially available metal oxide gas sensors, at an affordable cost.