ABSTRACT
This chapter analyzes the behavior of the diode in forward bias, introducing the parameters that determine the recombination rates. It observes the main features of current density–voltage curves. The chapter investigates the specific types of diodes like the Light-emitting diodes (LEDs), the molecular diodes represented by dye-sensitized solar cells (DSCs). It examines the features of the model in dark conditions. The chapter also investigates the fundamental model of the solar cell, based on the assumption of radiative recombination that produces the maximal theoretical efficiency. To analyze the interplay between light absorption, carrier densities, and photocurrents in a solar cell, it is important to first establish some basic properties that are settled in the dark equilibrium by detailed balance arguments that dictate recombination rates. The traffic of electronic carriers in the operation of a solar cell is governed by three elementary processes: light absorption, carrier recombination, and charge extraction.
