Voltage Scanning Speed Determination and Current-Voltage Curves of Different Types of Perovskite Solar Cells

Current-voltage ( I - V ) curve measurement is a widely used method to estimate the power conversion efficiency of a solar cell. Depending on the capacitance of the cell, a capacitive current could be induced by the voltage scanning speed ( v s ) that may affect the resulting I - V curve. However, in some source measure units (SMU), the relation of v s with the user controlled or external parameters is not explicit. In this article, we prepare and test three types of perovskite solar cells (PSCs), which include n-i-p and p-i-n structures, as well as mesoporous and planar cells. After a detailed analysis of the total testing time as a function of external parameters, it is found that there are internal parameters whose values are chosen by the SMU according to the selected external parameters to avoid longer testing times. As a result, v s can be explicitly described as a function of both external and internal parameters. For higher capacitive PSCs, smaller v s values reduce charge accumulation and lead into higher current (efficiency) and lower hysteresis index. A careful selection of the measuring parameters in a solar simulator and SMU is necessary to minimize testing artifact on capacitive PSCs.