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Regioselective iron-catalyzed cross-dehydrogenative coupling (CDC) of two aromatic compounds using tert-BuOOH as oxidant under mild conditions has been reported. The direct oxidative coupling reaction is selective toward creation of a carbon-carbon bond at the position ortho to the functional groups of the substrates, completely preventing the homocoupled products. The C-C bond-forming reaction makes the method versatile, leading to functionalized 2,2' -disubstituted biaryls.

A joint experimental and theoretical study on the stability of dye-sensitized Solar Cells employing a mixture of black dye (N749) and Y1 organic coadsorbent is presented. The aim of the present work is to investigate the stability of these sensitizers, representing the efficiency state of the art in this field. Under the investigated conditions (1100h of ~1Sun light soaking at 55˚C) the co-sensitized device has shown a remarkable stability. The partial desorption of the organic co-adsorbent has been individuated as a possible cause for the slight reduction of the photocurrent value. Theoretical investigations through DFT methods on the dye-sensitized semiconductor surface, revealed a considerably lower adsorption energy for Y1 compared to N749, in particular upon oxidation, possibly leading to the dye desorption under working conditions. Coherently, devices employing only the Y1 organic dye have shown a considerably lower durability.

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Two new metal-free organic sensitizers with simplest structural variations have been synthesized for application in nanocrystalline TiO2 sensitized solar cells. The donor-pi-bridge-acceptor (D-pi-A) structure dyes, Y2 and Y3 each designed with three parts, an electron donor unit (substituted phenyl), a linker unit (thiophene), and an anchor unit (cyanoacrylic acid) showed maximal monochromatic incident photon to current conversion efficiencies (IPCE) in a device reaching upto 67% and 82% respectively. The organic sensitizers with 3,4,5-trimethoxy phenyl (Y3) as donor moieties obtained better solar light to electrical energy conversion efficiencies of 3.30% where as the organic sensitizer with 2,4-difluoro phenyl as donor (Y2) showed comparatively lower efficiency of 1.02%. The efficiency obtained with the reference sensitizer N719 under similar fabrication and evaluation conditions was 5.84%.