Open AccessInsights into Nucleation and Growth of Colloidal Quaternary Nanocrystals by Multimodal X-ray Analysis
Author(s) -
Justus Just,
Claudia Coughlan,
Shalini Singh,
Haixia Ren,
Oliver Müller,
Pascal Becker,
Thomas Unold,
Kevin M. Ryan
Publication year - 2021
Publication title -
acs nano
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.554
H-Index - 382
eISSN - 1936-086X
pISSN - 1936-0851
DOI - 10.1021/acsnano.0c08617
Subject(s) - nanocrystal , small angle x ray scattering , materials science , nucleation , x ray absorption fine structure , chalcogenide , x ray absorption spectroscopy , nanorod , copper sulfide , copper , chemical engineering , nanoparticle , nanotechnology , absorption (acoustics) , scattering , absorption spectroscopy , spectroscopy , chemistry , optoelectronics , optics , organic chemistry , metallurgy , composite material , physics , engineering , quantum mechanics
Copper chalcogenide nanocrystals find applications in photovoltaic inks, bio labels, and thermoelectric materials. We reveal insights in the nucleation and growth during synthesis of anisotropic Cu 2 ZnSnS 4 nanocrystals by simultaneously performing in situ X-ray absorption spectroscopy (XAS) and small-angle X-ray scattering (SAXS). Real-time XAFS reveals that upon thiol injection into the reaction flask, a key copper thiolate intermediate species is formed within fractions of seconds, which decomposes further within a narrow temperature and time window to form copper sulfide nanocrystals. These nanocrystals convert into Cu 2 ZnSnS 4 nanorods by sequentially incorporating Sn and Zn. Real-time SAXS and ex situ TEM of aliquots corroborate these findings. Our work demonstrates how combined in situ X-ray absorption and small-angle X-ray scattering enables the understanding of mechanistic pathways in colloidal nanocrystal formation.