Photovoltaic, photoelectric and optical spectra of novel AgxGaxGe1−xSe2 (0.167 ≤ x ≤ 0.333) quaternary single crystals

In this paper, we report on the photovoltaic, photoelectric and optical properties of AgxGaxGe1−xSe2 single crystals (x = 0.333; 0.25; 0.20; 0.167). Investigation of optical and photoelectric parameters of AgxGaxGe1−xSe2 samples was carried out at different temperatures in the range 77–300 K. A large energy band gap (2.15–2.23 eV) for different values of x at T = 300 K and p-type conductivity make the titled AgxGa1−xGe1+xSe6 crystals as promising materials for substrates in heterojunctions based on wide-binary chalcogenide semiconductors A2V6 (their analogies), which have n-type conductivity. For the fabricated crystals, comparison of the thermoelectric conductivity measurements is performed. Role of intrinsic defects is also discussed.

► Single crystals of quaternary chalcogenide compounds AgxGa1−xGe2+xSe6 (x = 0.333; 0.25; 0.20; 0.167) were synthesized. ► Photovoltaic, photoelectric and optical properties were studied. ► Comparison of the thermoelectric conductivity measurements is performed.