The power conversion efficiency of a device incorporating a crystalline polymer/fullerene thin film improves from 5% to 7.3% – a relative increase of 45% – when an additive, diiodohexane (DIH), is present during processing. The DIH‐processed active layer exhibits substantially enhanced polymer crystallinity and smaller fractal‐like fullerene clusters.

Sodium titanate nanotubes (NaTNTs) are converted into monoclinic TiO 2 (B) nanotubes by rinsing with 0.10 M HCl followed by drying at 573 K. As calcination temperature is increased to 673 K, these TiO 2 (B) nanotubes start to transform into anatase nanoparticles producing a bi-crystalline mixture consisting of TiO 2 (B) nanotubes and anatase nanoparticles. The primary particle size of the anatase particles was estimated to be around 10 nm using Scherrer equation. After being promoted with 1% Pt, this bi-crystalline material becomes a very active photocatalyst producing 20% more H 2 gas than 1% Pt/Degussa P-25 TiO 2 in the photocatalytic dehydrogenation of neat ethanol after 2 h of UV light irradiation.

TiO 2 nanotubes promoted with Pt metal were prepared and tested to be the photocatalytic dehydrogenation catalyst in neat ethanol for producing H 2 gas ðC 2 H 5 OH ! C 3 CHO þ H 2 Þ. It was found that the ability to produce H 2 , the liquid phase product distribution and the catalyst stability of these promoted nano catalysts all depended on the Pt loading and catalyst preparation procedure. These Pt/TiO 2 catalysts with TiO 2 nanotubes washed with diluted H 2 SO 4 solution produced 1, 2-diethoxy ethane (acetal) as the major liquid phase product, while over those washed with diluted HCl solution or H 2 O, acetaldehyde was the major liquid phase product.

We have prepared photovoltaic devices based on blend films of CdSe tetrapods and the donor/acceptor conjugated polymer PDTTTPD, which comprises 2,5-di(thiophen-2-yl)thieno [3,2-b]thiophene and thieno [3,4-c]pyrrole-4,6-dione units. The AM1.5 power conversion efficiency (PCE) of a photovoltaic device containing a PDTTTPD/CdSe tetrapod blend (1 : 9, w/w) that had experienced thermal annealing (130 C, 20 min) was three times greater than that of the corresponding device incorporating the as-prepared PDTTTPD/CdSe tetrapod blend (2.9% vs. 1.0%). Synchrotron X-ray reflectivity revealed that annealing (i.e., removal of pyridine ligands from the surfaces of the CdSe tetrapods) caused the thickness of the PDTTTPD/CdSe tetrapod blend film to decrease (and its average density to increase) relative to that of the as-prepared blend film. Transmission electron microscopy and atomic force microscopy revealed that thermal annealing enhanced the degree of aggregation of the CdSe tetrapods and induced denser morphologies, leading to substantially increased charge transport, which enhanced the PCE of the device.

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