No abstract

Perovskite solar cells (PSCs) have gained increasing interest for space applications. However, before they can be deployed into space, their resistance to ionizing radiations, such as high-energy protons, must be demonstrated. Herein, the effect of 150 keV protons on the performance of PSCs based on aluminumdoped zinc oxide (AZO) transparent conducting oxide (TCO) is investigated. A record power conversion efficiency of 15% and 13.6% is obtained for cells based on AZO under AM1.5G and AM0 illumination, respectively. It is demonstrated that PSCs can withstand proton irradiation up to 10 13 protons cm À2 without significant loss in efficiency. From 10 14 protons cm À2 , a decrease in short-circuit current of PSCs is observed, which is consistent with interfacial degradation due to deterioration of the Spiro-OMeTAD holes transport layer during proton irradiation. The structural and optical properties of perovskite remain intact up to high fluence levels. Although shallow trap states are induced by proton irradiation in perovskite bulk at low fluence levels, charges are released efficiently and are not detrimental to the cell's performance. This work highlights the potential of PSCs based on AZO TCO to be used for space applications and gives a deeper understanding of interfacial degradation due to proton irradiation.

Rare-earth element erbium implanted into silicon was studied by photoluminescence and Rutherford backscattering analysis. Two sets of luminescent bands related to the weakly crystal field split spin-orbit levels 4I13/2→4I15/2 of Er 3+ (4f 11) at different lattice sites having different symmetries were observed.

From measurements over the last two years we have demonstrated that the charge collection system based on Faraday cups can robustly give near-1% absolute implantation fluence accuracy for our electrostatically scanned 200 kV Danfysik ion implanter, using four-point-probe mapping with a demonstrated accuracy of 2%, and accurate Rutherford backscattering spectrometry (RBS) of test implants from our quality assurance programme. The RBS is traceable to the certified reference material IRMM-ERM-EG001/BAM-L001, and involves convenient calibrations both of the electronic gain of the spectrometry system (at about 0.1% accuracy) and of the RBS beam energy (at 0.06% accuracy). We demonstrate that accurate RBS is a definitive method to determine quantity of material. It is therefore useful for certifying high quality reference standards, and is also extensible to other kinds of samples such as thin self-supporting films of pure elements. The more powerful technique of Total-IBA may inherit the accuracy of RBS.