The EU priority action lines state the need of low-cost production and efficient consumption of electricity, while the EU Sustainable Development Strategy Commission strongly encourages the further advance of PVs and LEDs following the “green photonics” concept: development of eco-friendly and highly stable materials for an efficient generation and use of the energy. In this context, the use of bio-molecules as operational compounds is a major challenge. The major limitation is their quick denaturation caused by light and temperature stress under device fabrication and operation conditions. However, their distinctive ecological features, such as unlimited low-cost production using bacteria and/or fully recyclable nature, strongly encourage their use as a model of sustainability. These limitations are also noted in bio-diagnosis, phototherapy, and bio-reactors. Here, stability and access of active bio-compounds is critical, hampering the commercial jump of many approaches. In addition, the working conditions also require low temperatures and irradiations. 

The problem statement relates to an urgent need for effective strategies to use biomolecules directly extracted from bacteria as functional components for developing sustainable and stable medical and energy-related technologies. This approach must ensure i) an excellent stability of the biofunctionality under storage and device operation conditions and ii) the use of 3D substrates and/or miniaturization.