Improving stability of organic devices: a time/space resolved structural monitoring approach applied to plasmonic photovoltaics

- The possibility to improve the efficiency and stability of organic photovoltaics via nanoparticles-based plasmonic devices was addressed.
- An unconventional approach, based on in-situ time/space resolved high spatial resolution synchrotron radiation X-ray diffraction applied to integrated devices, was used for the first time.
- The study allowed the kinetics of NP distribution inside the photoactive film and the nanoscale modifications of the structural/interface properties of each layer composing the device to be elucidated.

An unconventional approach is applied for the first time to study the effect of silver nanoparticles incorporation in plasmonic organic photovoltaic devices. The incorporation of silver nanoparticles in the photoactive film results in enhanced PV performance and stability with respect to the reference device. The role of the local morphology in improving the plasmonic device properties is addressed by time-resolved high spatial resolution X-ray diffraction investigations. TR-HRXD was performed in-situ on an integrated OPV device incorporating silver nanoparticles in the photoactive layer during annealing (simulating the working conditions). Such time-space resolved method allowed tracking the modifications of the structural properties at each layer and interfaces. Remarkably, it is demonstrated that it possible to track the variation of the plasmonic spatial distribution inside the device over time, a factor strongly influencing the photovoltaic performance.