Revealing Twinning in Gold Nanoparticles via Correlated X-Ray Scattering

Abstract

Correlated X-ray scattering (CXS) is an advanced technique that leverages the intensity correlations in photon scattering to probe the internal structures of nanoparticles (NPs) without the need for crystallization. In this study, we demonstrate the application of CXS combined with the high-brightness SACLA X-ray Free Electron Laser to distinguish twinning structures in gold nanoparticles (NPs). Our approach utilizes many snapshot exposures of an ensemble of gold NPs suspended in a lipid cubic phase. By analyzing the angular correlations in the scattered photons, we successfully identified the characteristic correlation peaks indicative of twinned structures, specifically nearest-neighbor twins (NNTs), which are not discernible using conventional powder diffraction methods. Our results not only confirm the presence of twinning but also highlight the complexity of these structures, potentially extending to multiply-twinned particles (MTPs). This work underscores the potential of CXS for detailed structural characterization of NPs. It paves the way for future studies on more complex soft matter systems and dynamic processes in NP growth and catalysis. Future advancements in X-ray sources, detector technology, and data processing algorithms will further enhance the resolution and applicability of CXS in nanomaterial research.