Examples of photoelectrochemical storage cells

1 PECS cells with solution-phase storage 

Earlier light-to-electricity conversion cells were often based on the photogalvanic effect, whereby light was absorbed in a dye in solution or adsorbed on an elecnode surface. The iron-thionine cell of Murphy (1978) provides an example of a photogalvanic device with storage. The forward reaction is  

Fe is slow. Leucothionine is selectively oxidised at the SnOi electrode 

Cell characteristics polycrystaUine Sn02 photoelectrode, Pt counter electrode, (/redox of Fe /Fe = 0.77 V vi. SHE, iUumination 40-50 mW cm by a tungsten lamp, initial current during discharge = 9.1 /iA, initial voltage = 10.9 mV. 

While this cell utilised a salt bridge to separate the two electrolytes, many systems used a membrane instead. Ang and Sammells (1980) provided an example of a membrane cell with a polycrystalline n-CdSe photoelectrode that drove a poly-sulphide/polyselenide storage couple. The cell had reasonable conversion efficiency (4%), but low output power density. The storage reaction and cell configuration are  

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