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Physical Sciences and Mathematics Commons

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Materials Chemistry

Selected Works

Sarah Cady

2019

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Persistent Dopants And Phase Segregation In Organolead Mixed-Halide Perovskites, Bryan A. Rosales, Long Men, Sarah D. Cady, Michael P. Hanrahan, Aaron J. Rossini, Javier Vela Sep 2019

Persistent Dopants And Phase Segregation In Organolead Mixed-Halide Perovskites, Bryan A. Rosales, Long Men, Sarah D. Cady, Michael P. Hanrahan, Aaron J. Rossini, Javier Vela

Sarah Cady

Organolead mixed-halide perovskites such as CH3NH3PbX3–aX′a (X, X′ = I, Br, Cl) are interesting semiconductors because of their low cost, high photovoltaic power conversion efficiencies, enhanced moisture stability, and band gap tunability. Using a combination of optical absorption spectroscopy, powder X-ray diffraction (XRD), and, for the first time, 207Pb solid state nuclear magnetic resonance (ssNMR), we probe the extent of alloying and phase segregation in these materials. Because 207Pb ssNMR chemical shifts are highly sensitive to local coordination and electronic structure, and vary linearly with halogen electronegativity and band gap, this technique can provide the true chemical speciation and composition …


Cu2znsns4 Nanorods Doped With Tetrahedral, High Spin Transition Metal Ions: Mn2+, Co2+, And Ni2+, Michelle J. Thompson, Kyle J. Blakeney, Sarah D. Cady, Malinda D. Reichert, Joselyn Del Pilar-Albaladejo, Seth T. White, Javier Vela Sep 2019

Cu2znsns4 Nanorods Doped With Tetrahedral, High Spin Transition Metal Ions: Mn2+, Co2+, And Ni2+, Michelle J. Thompson, Kyle J. Blakeney, Sarah D. Cady, Malinda D. Reichert, Joselyn Del Pilar-Albaladejo, Seth T. White, Javier Vela

Sarah Cady

Because of its useful optoelectronic properties and the relative abundance of its elements, the quaternary semiconductor Cu2ZnSnS4 (CZTS) has garnered considerable interest in recent years. In this work, we dope divalent, high spin transition metal ions (M2+ = Mn2+, Co2+, Ni2+) into the tetrahedral Zn2+ sites of wurtzite CZTS nanorods. The resulting Cu2MxZn1–xSnS4 (CMTS) nanocrystals retain the hexagonal crystalline structure, elongated morphology, and broad visible light absorption profile of the undoped CZTS nanorods. Electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and infrared (IR) spectroscopy help corroborate the composition and local ion environment of the doped …