First-principles investigation of the structural, dynamical and dielectric properties of kesterite, stannite and PMCA phases of Cu2ZnSnS4

摘要

Cu2ZnSnS4 (CZTS) is a promising material as an absorber in photovoltaicapplications. The measured efficiency, however, is far from the theoreticallypredicted value for the known CZTS phases. To improve the understanding of thisdiscrepancy we investigate the structural, dynamical, and dielectric of thethree main phases of CZTS (kesterite, stannite, and PMCA) using densityfunctional perturbation theory (DFPT). The effect of the exchange-correlationfunctional on the computed properties is analyzed. A qualitative agreement ofthe theoretical Raman spectrum with measurements is observed. However, none ofthe phases correspond to the experimental spectrum within the error bar that isusually to be expected for DFPT. This corroborates the need to consider cationdisorder and other lattice defects extensively in this material.