Spectral splitting photovoltaics using perovskite and wideband dye-sensitized solar cells

The extension of the light absorption of photovoltaics into the near-infrared region is important to increase the energy conversion efficiency. Although the progress of the lead halide perovskite solar cells is remarkable, and high conversion efficiency of >20% has been reached, their absorption limit on the long-wavelength side is similar to 800 nm. To further enhance the conversion efficiency of perovskite-based photovoltaics, a hybridized system with near-infrared photovoltaics is a useful approach. Here we report a panchromatic sensitizer, coded DX3, that exhibits a broad response into the near-infrared, up to similar to 1100 nm, and a photocurrent density exceeding 30 mA cm(-2) in simulated air mass 1.5 standard solar radiation. Using the DX3-based dye-sensitized solar cell in conjunction with a perovskite cell that harvests visible light, the hybridized mesoscopic photovoltaics achieved a conversion efficiency of 21.5% using a system of spectral splitting.open0

Efficient osmium sensitizers containing 2,2 '-bipyridine-4,4 '-bisphosphonic acid ligand.

The synthesis of a series of four complexes of the type Os(bpy-4,4'Po3H2)(2)L-2 (bpy-4,4'PO3H2 = 2,2'-bipyridine-4,4'-bisphosphonic acid and L-2 = Cl-2, (CN)(2), 2,2'-bipyridine-4,4'-bisphosphonic acid or 2,2'-bipyridine-4,4'-dimethoxy) is reported and the spectroscopic, photophysical, and photoelectrochemical properties are presented and compared to the cis-Ru(H(2)dcb)(2)(NCS)(2) (H(2)dcb = 2,2'-bipyridine4,4'-dicarboxylic acid)

Economic Evaluation of Biogas-to-Electricity Systems on Cage Layer Operations

Increased bird density on egg production operations has led to high electricity consumption and manure handling problems. Anaerobic diqestion offers a source of energy (biogas) and a consistent method of manure management. This paper reports the results of a computer simulation model desiqned to evaluate the economic viability of biogas-to-electricity systems on four egg farms containing different numbers of hens. These results indicate that the economic viability of the investment analyzed is directly related to the number of hens and projected electricity prices

Sensitization of TiO2 with ruthenium complexes containing boronic acid functions.

New ruthenium complexes based on bipyiridine and terpyridyne type ligands, containing boronic acid functions, of formulae: [Ru(bpy-OB(OH)(2))(2)(CN)(2)], 6, (bpy-Phi-B(OH)(2) = 4-(2,2'-dipyridil)phenylboronic acid), [Ru(trpy-B(OH)(2))(tb(2)bpy)Cl](PF6), 11, (trey-B(OH)(2) = 4-[4'-(2,2':6',2"-terpyridil]-boronic acid), [Ru(trpy)-Phi-B(OH)(2))(tb(2)bpy)Cl] (PF6), 12, (trey)-Phi-B(OH)(2) = 4-[4'-(2,2':6',2"-terpyridil]phenylboronic acid), have been prepared, characterized, and tested in dye-sensitized solar cells (DSSCs). The results of this first study indicate that: (i) the boronic acid function acts as interlocking group between sensitizer and mesoporous titanium dioxide; (ii) only the presence of two B(OH)(2) groups/molecule allow to obtain high photoanode surface coverages with optical densities > 1; (iii) The presence of the phenyl spacer in 12 reduces the photocurrent efficiency with respect to complex 11, most probably for a reduced electronic coupling between excited sensitizer and semiconductor conduction band. The insights gained from this work suggest that better photoelectrochemical performances should be obtained with dye molecules based on bpy type ligands bearing two boronic acid functions directly bound to the aromatic ring

Sensitization of nanocrystalline TiO2 with black absorbers based on Os and Ru polypyridine complexes.

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