Energy Sources Part A-recovery Utilization and Environmental Effects, Vol.35, No.6, 510-515, 2013
Use of Micelles in Photogalvanic Cells for Solar Energy Conversion and Storage: A Sodium Octanoate-Mannitol-Safranine System
The photogalvanic cell containing sodium octanoate (Anionic micelles) as micellar species, mannitol as an electron donor, and safranine as a photosensitizer has been used for solar energy conversion and storage. The electrical output of the cell as photopotential, photocurrent, and as power at power point were 860.0 mV, 330.0 A, and 285.1 W, respectively. The short circuit current Isc and open circuit voltage V oc of the photogalvanic cell were measured with the help of a multimeter (keeping the other circuit closed), and with a digital pH meter (keeping the other circuit open), respectively. The current and potential values between these two extreme values were recorded with the help of a carbon pot (log 470 K) connected in the circuit of a multimeter, through which an external load was applied. The current-voltage characteristics of the cell have been studied and with the help of i-v curve, the fill factor of the photogalvanic cell was determined as 0.44 using the following formula: where V pp = potential at power point, I pp = current at power point, V oc = open circuit voltage, and I sc = short circuit current. The fill factor of the photogalvanic cell was determined to be 0.44 and conversion efficiency was 1.5346%. The performance of the photogalvanic cell was observed by applying an external load (necessary to have current at power point) after terminating illumination as soon as the photopotential reaches a constant value. The performance was determined in terms of t 1/2 (i.e., the time required in fall of the power output to its half at power point in dark). It was observed that the cell can be used in the dark for 35.0 minutes in the presence of sodium octanoate.