Abstract:
Earth abundant Cu–Zn–Sn–S–Se (CZTSSe) is considered as a promising material for large area and cost
effective solar energy harvesting. The current efficiency of CZTSSe champion solar cell, 12.7%, is much
lower than that of its counterpart Cu–In–Ga–Se (CIGS) solar cell, 22.6%, and its theoretically predicted
Shockley–Queisser (SQ) limit, 32%. This performance disparity is because of a large voltage deficit,
0.62 V, in comparison to the optical band gap that primarily results from high carrier recombination at
the charge extraction interfaces. The different physical and chemical properties of interfacial layers often
cause unfavorable band alignment and interfacial states that lead to high carrier recombination and
eventually result in lower device efficiency. To obtain new insights about interfaces and to overcome the
interface-related pitfalls, research on interface engineering of solar cells is rapidly accelerating and
proven beneficial to achieve better device efficiency. This work provides a detailed strategic review on
carrier transport and carrier recombination mechanisms by probing different interfaces of Mo/CZTSSe/
CdS/i-ZnO/Al–ZnO/Al through every possible aspect. This review proposes eccentric approaches of
carrier management.
