In the last years, the photovoltaic industry has faced multiple challenges, from the progressive restriction of materials used to manufacture devices to the criticalities of on-demand availability of renewable energy. New alternatives to conventional semiconductors are being explored, especially in Europe, where the progressive bans of hazardous materials put the industry in a practical impasse. Energy storage systems have encountered the same challenges. Due to these circumstances, the need for adaptable and versatile energy storage and production systems rose sharply. This led research towards quantum dot based photovoltaic devices: their tunable bandgap allows the same material to cover absorption over different wavelength ranges. This, added to other peculiarities of these systems such as multiple exciton generation (MEG) and slow thermalization of the carriers, emphasized their applicability in the current photovoltaic landscape. Previous work has shown how these quantum dot systems have been implemented into devices to fabricate photodetectors, but the aim of this research is to explore the possibility to implement them into thermal storage systems called photon glow batteries, that would provide the possibility to retrieve energy stored in the form of thermal energy and reconvert it into current by photovoltaic effect. In my halftime seminar, I will show the progress I’ve made in the investigation of different quantum dot systems, from the synthesis of the QDs themselves and their characterization, to the production of the devices and the respective theoretical calculations for quantum dots inside a photon glow battery system.

Different 𝐴𝑔2𝑆𝑒 systems were investigated, especially from a perspective of synthesis control and different phase formation depending on synthesis parameters. Although the optoelectronic properties of these quantum dots could be emphasized by defect passivation. This led study of a three-phase system where gold is implemented in the structure. This 𝐴𝑔𝐴𝑢𝑆𝑒 system shows great promise for the integration in devices due to high PLQY values. Lastly, the concept of the photon glow battery is analyzed more in depth, and the implementation of a thermophotovoltaic device in the structure is studied taking into account as the active layer 𝐴𝑔𝐵𝑖𝑆 quantum dots and exposing them to infrared radiation.