TY - JOUR
T1 - Low-Temperature Tailoring of Copper-Deficient Cu3−xP – Electric Properties, Phase Transitions and Performance in Lithium-Ion Batteries
AU - Wolff, Alexander
AU - Doert, Thomas
AU - Hunger, Jens
AU - Kaiser, Martin
AU - Pallmann, Julia
AU - Reinhold, Romy
AU - Yogendra, Sivatmeehan
AU - Giebeler, Lars
AU - Sichelschmidt, Jörg
AU - Schnelle, Walter
AU - Whiteside, Rachel
AU - Gunaratne, H. Q . Nimal
AU - Nockemann, Peter
AU - Weigand, Jan J.
AU - Brunner, Eike
AU - Ruck, Michael
PY - 2018/9/17
Y1 - 2018/9/17
N2 - A convenient approach for a controlled and high-yield synthesis of copper-deficient Cu3−xP (0.1 < x < 0.7) is reported that makes use of ionic liquids with highly nucleophilic “naked” halide anions. Halide anions drastically enhance the reactivity of the white phosphorus precursor and kinetically disfavour the formation of phosphorus-rich side products. Cu3−xP shows a high degree of tolerance for cation vacancies without mayor structural reorganisation, as evidenced by X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy. Measurements of the electric 29 properties reveal that Cu3−xP is a bad metallic p-type conductor. The resistivity is composition-dependent and displays a distinct anomaly from a phase transition, leading to the discovery and structural characterisation of two hitherto unknown low temperature polymorphs. Electrochemical evaluation of copper-deficient Cu3−xP as anode material for lithium ion batteries reveals a drastic change in the cycling mechanism leading to an increase of the initial capacities by about 70 %. This work gives a comprehensive insight into the chemical and structural features of copper-deficient Cu3−xP and should lead to an improved understanding of its properties, not only for battery applications.
AB - A convenient approach for a controlled and high-yield synthesis of copper-deficient Cu3−xP (0.1 < x < 0.7) is reported that makes use of ionic liquids with highly nucleophilic “naked” halide anions. Halide anions drastically enhance the reactivity of the white phosphorus precursor and kinetically disfavour the formation of phosphorus-rich side products. Cu3−xP shows a high degree of tolerance for cation vacancies without mayor structural reorganisation, as evidenced by X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy. Measurements of the electric 29 properties reveal that Cu3−xP is a bad metallic p-type conductor. The resistivity is composition-dependent and displays a distinct anomaly from a phase transition, leading to the discovery and structural characterisation of two hitherto unknown low temperature polymorphs. Electrochemical evaluation of copper-deficient Cu3−xP as anode material for lithium ion batteries reveals a drastic change in the cycling mechanism leading to an increase of the initial capacities by about 70 %. This work gives a comprehensive insight into the chemical and structural features of copper-deficient Cu3−xP and should lead to an improved understanding of its properties, not only for battery applications.
UR - http://www.scopus.com/inward/record.url?scp=85054515120&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.8b02950
DO - 10.1021/acs.chemmater.8b02950
M3 - Article
AN - SCOPUS:85054515120
SN - 0897-4756
JO - Chemistry of Materials
JF - Chemistry of Materials
ER -