99.99%), zinc(II) acetate (Zn(OAc)2, 99.99%), palmitic
acid (PA, C15H31COOH, 99.99%, stored at
−20 °C), gallium(III) chloride (beads, Sigma-Aldrich,
99.99%), tris(trimethylsilyl)-phosphine (P(TMS)3, 95%), 1-octadecene (ODE, 95%), oleic acid (Sigma-Aldrich,
99.99%), ammonium sulfide solution ((NH4)2S,
20% in H2O), 1-octadecene (ODE, 95%), formamide (FA, 99%),
dimethylformamide (DMF, 99%), Zn stearate (technical grade),
sulfur powder (99.98% trace metals basis), and trioctylphosphine
(TOP, 90% technical grade) were purchased from Sigma-Aldrich. Selenium
powder (99.98% trace metals basis) was purchased by Chem Pure. All
the chemicals were used without further purification.