PHOTON · Perovskite-based Hybrid Optoelectronics: Towards Original Nanotechnology

Perovskite-based Hybrid Optoelectronics: Towards Original Nanotechnology

The overall objective of project PHOTON is to develop novel processing and analytical techniques for thin-film hybrid perovskite materials in order to understand and control its properties. Novel materials and processing have been applied to high-performance optoelectronic applications. The principal research objectives include the knowledge transfer between host and fellow, laboratory setup and training of future researchers. The aim was to enhance the host’s existing infrastructure and facilities in order to build a solid foundation for future research. Laser-based processing tools were studied and utlized in optoelectronic applications and the development of x-ray absorption techniques to study local atomic environment of materials developed at the host’s institute. One of the core advantages of the Paul Scherrer Institute (PSI) is its on-site large synchrotron facility. The experiments conducted at the Swiss Light Source (SLS) will be rich in fundamental science and should allow for a greater insight into the internal workings of this fascinating material system. The perovskite solar cell is a new and exciting breed of photovoltaic with photo-conversion efficiencies (PCE) verified as high as 20.1%. In terms of pure device performance, the perovskite-based photovoltaic has been astonishing. Thus, it appears that much of the current research effort is geared towards commercialisation. Large area devices, for example IMEC in Belgium are making great strides in this regard with PCEs of 12% for areas of 16 square cm2 . Stability also remains a key challenge that needs to be addressed. Following this line of reasoning, it is expected that progress in the vein of technological advances are likely to be piecemeal and step-wise at best with industry assuming much of the research and development effort. Thus future efforts should focus on more fundamental aspects of the technology. However, fundamental questions regarding the precise elemental make-up of this hybrid material and how to control its morphology at the micro-,nanoscale remain unanswered. Addressing such problems will influence the design rules for future photovoltaic development and accelerate efforts towards commercialisation. Laser-direct writing (LDW) is a remarkably simple method to fabricate highly ordered and functional micro/nano structured systems from a wide range of materials. The versatility of LDW enables complex materials to be deposited as a liquid, paste or solid with lateral directionality and high selectivity resulting in efficient material usage. Pastes and solids may be deposited with well-defined geometries (tuneable by rudimentary optics) and into functional 3D structures assembled through layer-by-layer direct-writing. The ability to pattern structures with great repetition rate, high reproducibility and well-defined spatial coordinates has led to the realisation of metamaterials by LDW. In accordance to phase alpha of project PHOTON knowledge transfer, laboratory setup and training has been completed. Novel hybrid perovskite materials have been synthesised in the new laboratory and rudimentary device work has begun. To improve efficiency device measurement and processing- electrical characterisation systems have been installed. For example precise conductivity measurements are now possible owing to the development of a four-probe measurement system. In accordance with project PHOTON, collaborations with the federal research institutes of Switzerland have been established and also collaborations abroad. A major aspect of this project is centred on the laser-processing of functional materials. Laser-induced forward transfer (LIFT) system has been used to print functional materials with great lateral directionality. The technique has been applied to high-performance silicon solar cells for the metallisation of silver electrodes. In this work we utilize LIFT as a means to provide metallization for high performance Si solar cells. Here, we detail the challenges of conformal coating of micron-scale electrodes of silver nanopastes over rough, randomly textured, pyramidal structures; we quantify the suppression of defects in the active layers through fluorescence spectroscopy; and we study the morphological and electronic properties of the deposited silver electrodes. This work was done in collaboration with researchers at EPFL (Swiss Federal Institute of Technology in Lausanne). The success of the LIFT project was extended to a new form of solar cell based on Copper Zinc Tin Sulfide (CZTS). This was done in an industrial setting with collaboration from IMRA. The company required metal electrodes with widths of around 70 micrometres, feature sizes as small as 15 micrometres were achieved. The fellow has established a work-group at the Paul Scherrer Institute (PSI) to study hybrid organic-inorganic perovskites at the SuperXAS beamline at the Swiss Light Source. The development of this work includes systems development, modificiations to the current large facilities were necessary for in operando studies. The newly augmented setup will enable study of the atomic structure of hybrid perovskite devices with and without light biasing (i.e., in operating mode). Sample fabrication and optimisation was done inconjunction with a master’s student from ETH (Swiss Federal Institute of Technology in Zurich.). Competency over the synthesis procedure was gained by the student and report was written. It is expected that European Research Area (ERA) will benefit from the State of the Art knowledge transfer and infrastructure enhancement will exist after the tenure of the fellowship, not only though enhanced infrastructure but through training of the future generation of scientists working in the field of novel thin-film hybrid materials. Further, the applied nature of the research proposed in project PHOTON is fundamentally interdisciplinary: drawing on knowledge from physics, organic and inorganic chemistry, materials science and engineering Novel approaches and alternative perspectives are often generated through the exchange of ideas at the interface between disciplines. New technology, such as the direct-laser writing of functional materials reported here, has the potential to enhance the livelihood and living standards of citizens. From a societal perspective, access to clean and renewable energy (for instance low-cost photovoltaics) and low-cost lighting (efficient light-emitting diodes) will reduce our reliance on polluting, unsustainable energy sources and reduce our energy consumption, respectively. Citizens will benefit from renewable energy research via more affordable energy, consequently the reduced reliance on fossil fuels will help reduce the causes of climate change, which will benefit everyone directly. The energy problem is relevant today, and it’s likely to become even more relevant in the near-future due to double envelopment of scarce natural resources and increasing energy usage, largely due to continued population growth. Solar energy is often seen as society’s only inexhaustible source of clean energy. From a political perspective, the ability to generate energy locally means reducing the reliance of imported energy from less politically stable countries, thus reducing geopolitical tensions and allowing greater energy independence.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз