Reaction Tailoring for Synthesis of Phase‐Pure Nanocrystals of AgInSe₂, Cu₃SbSe₃ and CuSbSe₂

Abstract

Present article highlights synthesis of phase pure I, III, VI2 and I, V, VI2 ternary selenides nanocrystals (NCs) using oleic acid and oleyl amine capping agents. The synthesis of AgInSe2 (AISe), Cu3SbSe3 and CuSbSe2 (CSSe) NCs was executed by employing cyclohexeno‐1,2,3‐selenadiazole (SDZ) as Se precursor. The current study is the first report describing use of thermally labile organoselenium compound for the synthesis of such technologically important ternary selenide NCs. Systematic study of the formation of AISe and CSSe NCs at different reaction time is carried out in order to confirm phase purity and stoichiometry. The spherical, stoichiometric and NIR active semiconductors showed formation of orthorhombic crystal structure as confirmed from XRD analysis. It was observed that formation of phase pure AISe NCs requires 5 hours (h) of constant heating at about 220οC irrespective of the capping agents however, CuSbSe2 was obtained within an hour in presence of oleyl amine at same reaction temperature. Nanocrystals were characterized by different analytical tools such as UV‐Visible spectroscopy, FTIR, XRD, SEM/EDS, TEM, particle size and XPS analysis. Based on the results, possible chemical reaction pathway for ternary chalcogenide is presented.

Ultra-small aqueous glutathione-capped Ag–In–Se quantum dots: luminescence and vibrational properties

“…20,21 The most popular way towards luminescent AISe and Zndoped AISe QDs is the incorporation of In 3+ into primary Ag 2 Se particles that can be achieved by relatively hightemperature hot-injection syntheses in coordinating solvents (such as trioctylphosphine or oleylamine). 9,10,15,20,[22][23][24][25][26][27][28][29][30][31][32] Typically, Se 0 is used as selenide precursor in these syntheses but sometimes rather exotic Se precursors are introduced to achieve ne control over the nucleation and growth of AISe QDs, such as bis(trimethylsilyl)selenide, 33 cyclohexeno-selenodiazole, 21,30 or Li[N(SeMe 3 ) 2 ]. 34 In the latter case, both composition and size of the AISe QDs can be independently varied resulting in "core" AISe and "core/shell" AISe/ZnSe QDs with a size from 2.4 nm to around 7 nm and three distinctly different compositions, Ag 3 -In 5 Se 9 , AgIn 3 Se 5 , and AgIn 11 Se 17 , while a top PL QY of 73% is observed for Ag 3 In 5 Se 9 cores with relatively thick ZnSe shells.…”

Morphology Transformation of Chalcogenide Nanoparticles Triggered by Cation Exchange Reactions

“…As an example, the Cu–Sb–(S/Se) family has proven to be of great interest to the photovoltaic research as the copper antimony sulfide (CuSbS 2 ) phase has shown promising features as absorber material. , CuSbS 2 NCs with different morphologies have been synthesized and even implemented in photovoltaic devices, but its selenide homologues have not been equally researched. There are just a few Cu–Sb–Se NCs synthesis reports to the best of our knowledge, , and despite the attempts, uniform morphology and compositions have not been achieved. All the previously mentioned studies had to use conventional routes (mainly hot injection) for the synthesis of the NCs as the ability of antimony ions to undergo CE reactions had not been successfully demonstrated.…”

Band Engineered I/III/V–VI Binary Metal Selenide/MWCNT/PANI Nanocomposites for Potential Room Temperature Thermoelectric Applications

“…The band gaps were estimated by plotting (α h ν) 2 = (1/ l ) 2 ( Ah ν) 2 versus h ν (Tauc’s plot), where α is the absorption coefficient, h ν is photon energy, l is the path length in centimeters, A and h are absorbance and Planck constant, respectively. − The band gap energies were much higher as the absorption profile was much blue-shifted for each metal selenide nanoparticles. Typically, the band gaps of AS, SS, IS, and CS were estimated to be 1.24 (bulk E g , 0.15 eV), 2.92 (bulk E g , 1.05 eV), 1.81 (bulk E g , 1.45 eV), and 1.70 (bulk E g ∼ 1.00 eV), respectively. − The higher band gap values obtained for all MSe NPs are correlated with a decrease in the particle size, which indeed was confirmed by other spectroscopic tools also.…”

“…The counterion of AS (i.e., selenide) showed peaks at 53.88 and 54.58 eV due to 3d 5/2 and 3d 3/2 states of selenium confirming the −2 oxidation state (Figure 1f AS). 64 The change in the peak position of the selenide is attributed to the change in counterion. Another sample IS showed two peaks due to 3d 5/2 and 3d 3/2 states at binding energies of 446.34 and 453.90 eV.…”