Mapping surface morphology and phase evolution of iron sulfide nanoparticles. Issue 33 (5th August 2021)

• Record Type: Journal Article
• Authors: Yang, Tao; He, Yurong; Liu, Xiaotong; Liu, Xiulei; Peng, Qing; Li, Ning; Liu, Jinjia
• Is Part Of: CrystEngComm. Volume 23:Issue 33(2021)
• Page Start: 5645
• Page End: 5654
• Publication Date: 2021-08-05
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/d1ce00800e
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : The size effect on the thermodynamic phase diagram of Fe x S y nanoparticles. Abstract : Iron sulfide nanoparticles play an essential role in the global biogeochemistry sulfur cycle and the origin of life. Controlling phase and morphology is essential but a great challenge for nanomaterials. Herein, we have investigated surface energy, morphology, thermodynamic stability, and phase evolution of Fe x S y nanoparticles through density functional theory calculations and Wulff construction. The sulfur-rich surfaces become more stable under higher sulfur chemical potential with low temperature and high partial H2 S pressure, while the trends of sulfur-poor surfaces are reversed. Thermodynamic equilibrium phase diagrams imply that the intrinsic iron is sulfurated to mackinawite (FeS) and further to the polymorphs of FeS2 when the particle size is larger than 5 nm. When the size is decreased to 2 nm, the mackinawite (FeS) could be sulfurated to pyrrhotite (Fe7 S8 ) and greigite (Fe3 S4 ) and finally to the pyrite (FeS2 ) phase.