The phase formation, morphology evolution and bandgap of Sn 1-xSbxSe (0 ≤ x ≤ 0.6) nanocrystals synthesized at 230-275 °C for 5-36 h in a one-pot system were studied. Sn2+ is kinetically more reactive than Sb3+ toward Se2-. The SnSe(1) phase (JCPDS 01-075-6133) grew in the Sn1-xSbxSe (0 ≤ x ≤ 0.2) nanocrystals, while the SnSe(2) phase (JCPDS 32-1382) was dominant in the Sn1-xSbxSe (0.3 ≤ x ≤ 0.6) nanocrystals. In the present study, the substitution solubility of Sb in the SnSe lattice is about 10 at%. The introduction of more Sb in the Sn 1-xSbxSe (0.3 ≤ x ≤ 0.6) nanocrystals induced more defects therein and thus caused the phase transformation from SnSe(1) to SnSe(2). The SnSe nanocrystals grew as nanosheets, while the introduction of Sb enhanced the growth of Sn1-xSbxSe nanorods. The direct and indirect bandgaps of the Sn1-xSbxSe (0 ≤ x ≤ 0.2) nanocrystals could be tuned from 1.39 to 1.53 eV and 0.93 to 1.28 eV, respectively, by increasing the Sb concentration (x) from 0 to 0.2. The tunable morphology and bandgap of the Sn1-xSbxSe nanocrystals make them potential candidates as photovoltaic materials.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics