Piezo-Photodiode from Rochelle Salt and Methyl Red Layers

For future applications in simultaneous detection of sunlight and mechanical oscillations, a piezo-photodiode with a structure of aluminium (AI)/ Rochelle salt (RS)/ Methyl red/ indium-tin-oxide (ITO)/ Glass was created. A piezo layer of RS was deposited on the aluminium substrate by electrophoresis, and then the RS layer was flooded with Methyl red solution, and after drying, the organic photosensitive layer was obtained. The piezo modulus d33
$=240\text{pC}/\mathrm{N}$
, which is characteristic of the salt, was measured on this intermediate structure. The piezo photodiode structure was completed by placing ITO)/Glass on top. Applying a voltage of -2V to
$+2\mathrm{V}$
gave a typical diode I-V characteristic and a dark current of -0.2 to
$+0.32\text{nA}$
was measured. After irradiation with visible light, a difference between the photocurrent and the current in the dark was observed, and at a voltage of
$+1.4\mathbf{V}$
, the photocurrent was already twice as large. After simultaneous irradiation and mechanical vibration of the structure, the peak photocurrent increases twice more. Research shows that in the future, devices can be created to simultaneously capture and detect energy from multiple sources.