Phase-pure iron pyrite nanocrystals for low-cost photodetectors

Table 1 The experimental parameters used for the hydrothermal synthesis of FeS ₂ nanoparticles

Sample number	[S]/[Fe]	Reaction time (hour)	PH	Phase and impurities	Morphology
1	1/1.5	24	11.5	FeS₂ + Fe_xO_{1 - x} + S	Polygonal nanoparticles
2	1/0.75	24	11.5	FeS₂ + Fe_xO_{1 - x} + S	Polygonal nanoparticles
3	2/1	48	12.3	FeS₂ + Fe_xO_{1 - x}	Nanorods
4	2.5/1	48	12.3	FeS₂ + Fe_xO_{1 - x}	Nanocubes and polygonal nanoparticles
5	3/1	48	12.3	FeS₂ + Fe_xO_{1 - x}	Nanocubes and hierarchical particles
6	3.75/1	48	12.3	FeS₂	Hierarchical particles

[S]/[Fe] represents the molar ratio between sulphur and iron elements. The reaction temperature is maintained at 200°C.