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To unleash the full potential of hybrid solar cells, it is imperative to get significant photocurrent contribution from both the sensitizing dye and the polymeric hole transporter. Here we report on the interfacial modifier 4-mercaptopyridine (4-MP), which induces controlled orientation of poly(3-hexylthiophene) (P3HT), the most widely used hole transporting polymer for hybrid solar cells, at the interface. 4-MP optimizes the charge separating interface between P3HT and a squaraine dye-decorated TiO2, inducing enhanced contribution to photocurrent generation by the polymer. In combination with 4-tert-butylpyridine, which enhances the open circuit potential in dye-sensitized and hybrid solar cells but reduces the photocurrent, a synergistic effect is observed and it is possible to enhance both open circuit voltage and photocurrent simultaneously. Similar effects on device performance are also found for two other commonly used dye molecules, a fullerene derivative and a common indoline dye.

Polycrystalline chalcopyrite absorbers in thin film solar cells exhibit distinct spatial inhomogeneities which are obviously introduced during growth of the grainy structure. Amongst several structural inhomogeneities in scale lengths of grains of one ?m or below, spatial variations of optoelectronic properties in much larger scales of some ?m can be observed, such as fluctuations in the splitting of quasi-Fermi levels in the range of several tens of meV. These have been quantitatively deduced via Planck's generalized law from spectrally resolved confocal room temperature luminescence scans. Since the necessary absorption length in thin film semiconductors is in the neighborhood of the wavelength of photons, for the evaluation of luminescence spectra wave optics with multireflection effects have been applied.

This paper deals with the interaction of the electromagnetic pulse environment generated by high altitude bursts (HEMP) with transmission lines. The environments is determined from the EXEMP computer code (Theoretical Notes Nos. 363 to 365). The coupling of these fields to above-ground conductors is then obtained by time-domain transmission line theory (TLT) assuming a perfectly conducting earth. In particular, the contributions of the vertical potential differences at the end of semi-infinite horizontal lines and different types of vertical line elements (vertical risers) are also discussed within the framework of the TLT rules. The paper presents open-circuit voltages induced in transmission lines at distinct locations within the illuminated area as well as contour plots of peak voltages and cumulative voltage distribution functions.