Insight into the Mechanochemical Synthesis and Structural Evolution of Hybrid Organic–Inorganic Guanidinium Lead(II) Iodides

Abstract

The in situ investigations of the mechanochemical synthesis of four hybrid organic-inorganic lead(II) iodides with the formula (C(NH ) ) PbI (n=1, 2, 3, and 4) are presented. Synchrotron X-ray diffraction data show that the four guanidinium lead(II) iodides easily convert into each other. Although the end product is dictated by the initial stoichiometry, complex pathways were found with different behaviors of the compounds in terms of nucleation, growth, and intermediate formation. This appears to be linked to the respective structural features of the different compounds, especially the connectivity of the inorganic framework and the strength of ionic interactions. High-temperature studies were conducted on compounds 1, 3, and 4 to reveal the new phases 1-II, 3-II, and 3-III. Unknown structures were solved from single-crystal analysis and powder X-ray diffraction.

Mechanochemical Synthesis of Sn(II) and Sn(IV) Iodide Perovskites and Study of Their Structural, Chemical, Thermal, Optical, and Electrical Properties

“…Although this compound can be seen as a 0D structure due to the fact that adjacent SnI 6 octahedra do not share any corners, their vicinity and consequent orbital overlap results in interesting optoelectronic properties for PV . Mechanochemical synthesis via ball‐milling or other techniques (e.g., hand grinding) provides an ideal platform to form a wide variety of perovskites in stoichiometric and solvent‐free conditions …”

Changing the Game of Time Resolved X-Ray Diffraction on the Mechanochemistry Playground by Downsizing

“…Despite the growing number of TRIS synchrotron studies being reported, the collection of quality diffraction data has proved a difficult task with conventional setups and data collection strategies. 12,32,33 An innovative and highly successful solution was presented by Ban et al 34,35 who improved the signal to background ratio using a new design of milling jar. In their design, the X-ray beam was focused through a specially designed sampling chamber on the outer circumference of the milling jar, with small width and narrow walls.…”

Recent Advances and Perspectives on Powder‐Based Halide Perovskite Film Processing

“…In the past, the mechanochemical synthesis of different halide perovskites has been demonstrated, including almost all combinations of the organic A-site cations MA + or FA + and X-site halides Cl -, Bror I in the case of ternary lead halide perovskites, as well as multinary mixtures thereof. [22][23][24][25] The successful introduction of additional cations, such as guanidinium (Gua + ), [26,27] rubidium (Rb + ), [28] and especially cesium (Cs + ), [20,29,30] via mechanochemistry extends the range of available stoichiometries, including the mechanochemical synthesis of the completely inorganic halide perovskites CsPbX 3 . [31][32][33] By the addition of appropriate organic molecules, it is possible to synthesize perovskite nanocrystals.…”