NiO/perovskite interface with novel NiO precursor was investigated with Auger profiling for solar cell with PCE > 15%.

A novel type of tunable organic photovoltaic (OPV) tandem device with ionic gating by in-situ ionic liquid is presented. This device is comprised of two solution-processed polymeric OPV cells connected in parallel by a dry-laminated transparent multiwall carbon nanotube (MWCNT) interlayer. The interlayer MWCNT of this 3-terminal tandem device plays a role of a common electrode with a Fermi level that can be tuned via ionic gating to turn it into a common cathode, collecting photo-generated electrons from both sub-cells. Ionic gating employs electric double layer charging of the MWCNT in order to lower the work function of the common CNT electrode and increase its n-type conductivity. This tandem device is fabricated in ambient conditions via dry-lamination of MWCNT transparent sheets The new results demonstrating the different regimes of ionic gating at low, medium, and high gating voltages Vgate are presented, showing the optimal doping of the MWCNT, then favorable doping of acceptor PCBM ([6,6]-phenyl-C61-butyric acid methyl ester), followed by the deterioration of performance at Vgate over the threshold voltage when doping of polymeric layers of sub-cell OPVs starts taking place. The doping of PCBM and polymers is additionally confirmed by the change in the charging and discharging current dynamics at high Vgate above the threshold.

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The n-type and p-type a-GaN films were successfully grown on a r-sapphire substrate, according to X-ray diffractometer and SEM results parameters measurement. The growth rate versus the growth temperature was investigated. The holes concentration (8x1017 cm−3) was achieved by the Cp2Mg flow optimization and the parameters of thermal annealing in nitrogen. The GaN film growth rate dependence versus temperature at a constant hydrogen flow through a TEG source was investigated. The results indicate that defects density is reduced upto 104 cm−2, the surface morphology uniformity was improved. During growth the influence from V/III flows ratio was detected.

Organic photovoltaics, based on hybrid inorganic organic optoelectronic perovskites, with structure alkali-metal-halide are the newest emerging technology in the third generation development. Despite tremendous efficiency records, more than 21 %, optoelectronic perovskites' instability prevents their commercialization and mass production. Issues with degradation are caused by various types of environmental influences. The main issues with stability and power loss in devices are linked to moisture, oxygen, temperature, and light-induced structure defects. Initial measurements are taken after long term debugging with minimal aggressive exposure to environmental conditions. In this case, preliminary degradation studies begin from measurements of light-induced effects. In this work, we will present the main trends in degradation of external characteristics during common I-V measurements, in the order of parameters which were effected the least by environmental factors. This investigation was made on fixed CH3NH3PBI3 solar cells with standard 1.5 AM testing and initial efficiencies more than 8 %.

This article presents the results of research output voltage characteristics of solar cells on an organic basis with the use of P3HT: PCBM system. There were produced organic solar cells in a coating in air, current-voltage characteristics were measured. It was determined the characteristic influence of a substrate cleaning and annealing temperature of layers applied on fill factor and conversion efficiency.

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The n‐type and p‐type a‐GaN films are successfully grown by MOCVD on the r‐sapphire substrate with smooth mirror surface morphology. The growth rate versus the growth temperature is investigated. Optimum doping parameters by acceptor and donor impurities − 8 × 1017 and 4 × 1018 cm−3 are determined. Low‐temperature amorphous buffer (nucleus) GaN layer and the island growth process with additional doping profile in quantum wells (QW) are investigated. The heterostructures are grown based on direct investigation and simulation results and are investigated by atomic‐force microscopy (AFM) and scanning electron microscopy (SEM). In this work, V‐defects of the structure for non‐polar orientation films are investigated for the first time, thus complementing earlier results for polar and semi‐polar films. The results indicate that the defect density was reduced up to 104 cm−2, with improved surface morphology uniformity. During growth, the influence from V/III flow ratio and doping barriers by indium atoms was detected. Decrease in the V/III ratio up to 1320 at the overgrowth stage of the precipitated low‐temperature nuclei caused growth‐island formation and increased the growth rate in the lateral direction, thus decreasing the dislocation density.