Charge Carrier Dynamics in Perovskite Solar Cells

In this chapter, we illustrate the fundamental photophysics, charge carrier dynamics, and interfacial processes in organolead trihalide perovskite solar cells (PSCs). The first section presents the evaluation of important electrical parameters such as charge carrier mobility, electrical conductivity, carrier concentration, trap density, and distribution in perovskite layer using space charge-limited conduction (SCLC) method. In the second section, we explain the electrical response of materials to an alternating voltage through immittance spectroscopy. The technique comprises a range of electrical methods such as impedance, admittance, capacitance, dielectric spectroscopies, and Mott–Schottky (MS) analyses. These methods provide insight of the electrical properties such as electrical and ionic transport, charge accumulation, charge relaxation process, trap density, interfacial phenomenon, lattice distortions, and electrode polarization in PSCs. Further, the dynamics of photogenerated charge carriers in PSCs have been elucidated via transient spectroscopic techniques including transient absorption spectroscopy (TAS), time-resolved photoluminescence (TRPL), and time-resolved microwave conductivity (TRMC). The estimation of important photophysical parameters such as mobility of charge carriers, carrier concentration, trap density, electron–hole recombination kinetics, and charge carrier lifetime has also been discussed here.