Table 1. Optical Band Gap (eV) and Urbach Energy (meV) in Relation to the Nominal Se Content in the Samples.

Se content	band gap (eV)	Urbach energy (meV)
0.48	1.153 ± 0.022	70.12 ± 0.91
0.50	1.150 ± 0.027	41.80 ± 1.20
0.52	1.144 ± 0.012	24.80 ± 0.37
0.53	1.151 ± 0.008	23.49 ± 0.34
0.54	1.154 ± 0.006	22.99 ± 0.32