Acceptor

Abstract: the oxygen acceptors originally used were 0 tolidine, benzidine and o-dianisidine. It has since been established that these three substances are carcinogens and many alternative oxygen acceptors have been suggested. Any dye showing oxidation-reduction properties or any dye formed by oxidation, such as those used in colour photography, are potentially useful but it is obviously advantageous to use reagents which have high stability. For manual work on blood a two-solution technique is desirable, one solution being used to precipitate the protein and the other to develop the colour. The development of such a method will now be described. In the determination of phosphatase, use is made of the fact that phenol in the presence of an oxidising reagent gives a purple colour with 4-amino phenazone. The possibility that the H.Oz released in the reaction of glucose oxidase with glucose could act as the oxidising agent was investigated and it was found that the system of phenol and 4-amino phenazone is well suited to the determination of glucose. By suitable adjustment of conditions the colour develops completely in 10 minutes, being stable thereafter for at least 30 minutes. Using a single-solution phosphotungstic acid precipitant containing phenol to precipitate blood protein the only other solution required is one containing glucose oxidase, peroxidase and 4-amino phenazone. These solutions contain azide as preservative; azide has no effect on the rate of colour development. In the micro and macro automated methods, the two solutions required are a diluent containing 4-amino phenazone and a colour reagent containing glucose oxidase, peroxidase and phenol.

Abstract: A novel non-fullerene electron acceptor (ITIC) that overcomes some of the shortcomings of fullerene acceptors, for example, weak absorption in the visible spectral region and limited energy-level variability, is designed and synthesized. Fullerene-free polymer solar cells (PSCs) based on the ITIC acceptor are demonstrated to exhibit power conversion effi ciencies of up to 6.8%, a record for fullerene-free PSCs.

Abstract: A series of highly soluble fullerene derivatives with varying acceptor strengths (i.e., first reduction potentials) was synthesized and used as electron acceptors in plastic solar cells. These fullerene derivatives, methanofullerene [6,6]-phenyl C61-butyric acid methyl ester (PCBM), a new azafulleroid, and a ketolactam quasifullerene, show a variation of almost 200 mV in their first reduction potential. The open circuit voltage of the corresponding devices was found to correlate directly with the acceptor strength of the fullerenes, whereas it was rather insensitive to variations of the work function of the negative electrode. These observations are discussed within the concept of Fermi level pinning between fullerenes and metals via surface charges.