Chai S, Xiong J, Zheng Y, Shi R, Xu J. Dielectric phase transition of an A
2BX
4-type perovskite with a pentahedral to octahedral transformation.
Dalton Trans 2020;
49:2218-2224. [PMID:
32003371 DOI:
10.1039/c9dt04270a]
[Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Organic-inorganic hybrid compounds that undergo reversible dielectric phase transitions are a very attractive class of smart materials due to their wide applications in data storage, data communication and signal sensing. Here, a piperidine ring, C5H11N, was introduced into the inorganic lead halide perovskite scaffold to obtain three hybrid perovskite compounds, [C5H12N]2PbCl4 (1), [C5H12N]2PbBr4 (2), and [C5H12N]PbI3 (3). When compound 2 and compound 3 feature static two-dimensional (2D) and one-dimensional (1D) perovskite structures, respectively, it is striking that compound 1 shows a reversible pentahedral to octahedral transformation. It undergoes an above-room-temperature dielectric phase transition at Tc≅ 352 K, wherein the high dielectric constant is more than twice the low dielectric constant. Structural analysis shows that 1 undergoes a phase transition from the space group Pnma at the low temperature phase (LTP) to C2/c at the high temperature phase (HTP). The phase transition originates from the order-disorder conversion of piperidinium cations. It is interesting to note that, the Pb2+ cations in the inorganic moieties change from five-coordinate at the LTP to six-coordinate at the HTP. The discovery of dielectric phase transition hybrid organic-inorganic lead halide perovskite materials further enhances the potential applications of high temperature responsive dielectric switchable materials.
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