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Exploring Route for Pyrophosphate‐based Electrode Materials: Interplay between Synthesis and Structure
Author(s) -
Alekseeva Anastasia M.,
Tertov Ilya V.,
Mironov Andrey V.,
Mikheev Ivan V.,
Drozhzhin Oleg A.,
Zharikova Emiliya V.,
Rozova Marina G.,
Antipov Evgeny V.
Publication year - 2020
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/zaac.202000066
Subject(s) - pyrophosphate , vanadium , sodium , chemistry , crystal structure , crystallography , hydrate , dehydration , hydrothermal synthesis , inorganic chemistry , hydrothermal circulation , chemical engineering , organic chemistry , biochemistry , enzyme , engineering
New sodium vanadium(III) hydrogenphosphate hydrate NaV(HPO 4 ) 2 (H 2 O) 0.5 and sodium vanadium(III) hydrogenphosphate β‐NaV(HPO 4 ) 2 were prepared in mild hydrothermal conditions. The crystal structures of NaV(HPO 4 ) 2 (H 2 O) 0.5 [space group Cc, Z = 4, a = 8.46174(19) Å, b = 9.52583(19) Å, c = 8.69376(15) Å, β = 110.9553(11) °, V = 654.41(2) Å 3 ] and β‐NaV(HPO 4 ) 2 [space group C 2/ c, Z = 4, a = 7.8681(3) Å, b = 9.8451(3) Å, c = 8.5180(2) Å, β = 107.626(2) °, V = 628.85(3) Å 3 ] were solved and refined from X‐ray powder diffraction data. Both compounds were used as precursors in a new route for the preparation of attractive cathode material β‐NaVP 2 O 7 . The formation of the structure motive providing fast sodium ion diffusion at the first synthesis stage and its further conservation upon stepwise dehydration was revealed. The oversized Na + ‐embedding channels are stabilized by site‐coordinated water in NaV(HPO 4 ) 2 (H 2 O) 0.5 structure. The topology resemblance and difference in known sodium vanadium(III) complex phosphates are discussed.