Formation of a crystalline InSe phase from a quaternary single crystal of the Cu–Ag–In–Se system by massive ion motion

The interface effect on the I–V curves and analysis of ionic diffusion coefficients of polycrystalline CuIn4Te6

“…) and InTe regions could be formed as previously observed in similar compounds [8]. Both possibilities would indicate that the compound structure would have a lower number of defect pairs and vacant sites than 2 months ago [7,8].…”

“…Both possibilities would indicate that the compound structure would have a lower number of defect pairs and vacant sites than 2 months ago [7,8]. In series C, a lower number of vacancies would make difficult the ion motion, and therefore, the resistance related to ion motion, R 1 , would be higher than in series A and B (R 1 (series C)/R 1 (series A)~170).…”

“…However, in MIECs with high ionic conductivity, strong effects are observed in the electrical properties due to their ionic motion. We have found that In rich chalcopyrites as CuIn 3 Te 5 , Cu 0.9 Ag 0.1 In 3 Te 5 and Cu 0.9 Ag 0.1 In 3 Se 5 belong to this kind of high ionic conductivity MIECs [7][8][9]. They show a resistance change under application of a constant potential that can be associated with the existence of two mobile ions blocked at the interface.…”

“…The existence of the DADP permits the Cu and In Cu 2+ motion through Cu vacant sites. AB n−3 -III n+1 -VI 2n compounds with n=4, 5,6,7,8,9 can be formed with a very similar structure and different number of DADPs depending on the n value [10]. In nanoscale MIECs with low ionic motion, new I-V relations under a slowly varying applied voltage may appear due to the ion motion [6].…”

“…The gradient in the ion electrochemical potential is the driving force for the ionic motion. In MIECs with two mobile ions and high diffusion coefficients as CuIn 3 Te 5 , Cu 0.9 Ag 0.1 In 3 Te 5 and Cu 0.9 Ag 0.1 In 3 Se 5 , the ions move a distance that alter their concentration along the sample and different compositions can appear in the bulk and at the interfaces due to the ionic accumulation produced when an external voltage is applied [7][8][9].…”