[Photovoltaic behavior of chlorophyll a and beta-carotene in Langmuir films].

The photovoltaic properties of chlorophyll a and beta-carotene Langmuir films and Langmuir films of a mixure of chlorophyll a and beta-carotene at different molar ratios were investigated. SnO2-optically transparent electrodes were used as a support. It was shown that the film photovoltage value depends on surface pressure and the total film thickness (the number of layers deposited onto SnO2-optically transparent electrodes). Fifteen layers (SP = 35 mH/m) of chlorophyll and 7-10 layers (SP = 20 mH/m) of beta-carotene give rise to a maximal photovoltage of 140 and 270 mV (at a shunt resistance of 10(7) Ohm), correspondingly. It was found that the photovoltage values in films of the carotene-chlorophyll mixture increase with the carotene concentration. The photovoltage value of a film containing 80-90% of carotene exceeds that of single-component pigment films prepared under the same deposition conditions.