Di n octylamine

Gallium chloride (GaCl₃, 99.999%, anhydrous) and gallium
tris(dimethylamide) dimer (Ga₂(NMe₂)₆ 99%) were purchased from ABCR; lithium dimethylamide (LiNMe₂, 95%), di-n-octylamine (DOA, 98%), di-n-dodecylamine (DDA, ≥ 97%), 1-octadecene (ODE, 90%),
and oleic acid (OA, 90%) were obtained from Sigma-Aldrich. DOA, ODE,
and DDA were degassed and dried under vacuum at 110 °C for 90
min, cooled to room temperature, and transferred airless to the glovebox.
All other chemicals were used as received. The syntheses of Ga₂(NMe₂)₆ and Ga NPs were carried out
under inert atmosphere using the glovebox and Schlenk line technique.
Post-synthetic purification (“washing”), handling, and
storage of Ga NPs were performed under ambient conditions.

Di-n-octylamine (+98%), di-n-pentylamine
(99%), di-n-propylamine (99%), diethylamine (>99.5%),
phenethylamine
(≥99%), n-dodecylamine (≥99%), n-octylamine (+99%), n-pentylamine (+99%), n-propylamine (+98%), Cd(OAc)₂·2H₂O (>98%), trin-octylphosphine (TOP) (97%), and
oleylamine
(or cis-9-octadecenylamine, technical grade, 70%) were obtained from
Sigma-Aldrich. Selenourea (99.9%, metal basis) was obtained from Alpha
Aesar. All were used as received and stored under N₂. Toluene
was obtained from Sigma-Aldrich (CHROMASOLV for HPLC, ≥99.9%).
Transmission electron microscopy (TEM) sample grids (Cu with holey
carbon film) were obtained from Ted Pella, Inc.
All synthetic
procedures were conducted under dry N₂, except the final
washing steps, which were conducted in the ambient atmosphere. The
reaction mixtures were not stirred. The synthetic products were generally
stored as reaction mixtures, after addition of TOP (see below).