Organic semiconductors are an emerging class of materials with various optoelectronic applications. To enable faster commercialisation of this technology, there are two requirements: (i) improve their performance and (ii) follow eco-friendly manufacturing strategies.

Improving their performance is a key requirement to enable faster commercialisation. Charge carrier mobility is one crucial parameter for electronic applications, particularly organic thin film transistors (OTFTs). A generic approach to achieve this is through the addition of molecular dopants in the organic semiconductor layer. Here, we report the use of novel materials as molecular dopants for both p^1,2 and n-type^3,4 organic semiconductors in OTFT devices. We show that key device parameters such as charge carrier mobility, contact resistance and threshold voltage improve dramatically upon adding the dopant. The effect of the dopant was analysed with Electron Paramagnetic Resonance (EPR) and by extracting the activation energy (EA) from low-temperature electrical characterisation. The impact of the dopant on the morphology of the OSCs will also be discussed as studied from Atomic Force Microscopy (AFM) and X-Ray diffraction (XRD). Overall, this work highlights that controlled doping of organic semiconductor materials is the key to enhanced electronic devices.

In the second part of the talk, I will introduce sustainable routes to manufacture solution-processed organic electronics. Particular focus will be given to organic solar cells, which recently attracted immense attention due to the development of a new family of semiconductors that allows highly efficient light harvesting in indoor and outdoor conditions. One current limitation, though, is the use of not eco-friendly solvents and materials during the device development stages. Most organic electronic devices require halogenated and non-halogenated aromatic solvents during their fabrication. For large-scale production and further commercialisation, this is a key limitation. This arises from the fact that organic semiconductors are highly soluble in this category of solvents, which are often carcinogenic or toxic to the human reproductive systems and negatively impact the environment. Here I will show high-performing organic solar cells fabricated from biomass-based solvents.⁵. Overall, this work highlights the importance of replacing harmful chemicals and materials in the organic electronics fabrication stages, resulting in faster and wider commercialisation and new market opportunities.