Photoconductivity of α‐Methylnaphthalene Alone and with an Incorporated Solute

Exposure of α‐methylnaphthalene to strongly absorbed uv light and externally applied voltage produced photocurrent in the range of 10−9 to 10−7 A/cm2; their magnitude depended on the polarity of the illuminated electrode. The illumination through the positive electrode gave a photocurrent 15 times greater than when the negative electrode was illuminated. The mobilities of the positive and negative carriers were determined to be 1.2×10−4 and 5×10−5 cm2/V·sec, respectively. The former value is of the same order of magnitude as the theoretical value calculated for a positively charged α‐methylnaphthalene ion. The temperature dependence of the mobility of the positive carrier indicated that the carrier may be either an ion or a hole with a long hopping time. Current—voltage measurements show that saturation is not reached at the highest field strength employed, 40 000 V/cm, and most likely would not be reached below fields of 106 V/cm. On this basis a theoretical efficiency of 1% for charge production was est...