Dimensionality Engineering of Lead Organic Chalcogenide Semiconductors

Abstract

Two-dimensional (2D) metal organic chalcogenides (MOCs) such as silver phenylselenolate (AgSePh) have emerged as a new class of 2D materials due to their unique optical properties. However, these materials typically exhibit large band gaps, and their elemental and structural versatility remain significantly limited. In this work, we synthesize a new family of 2D lead organic chalcogenide (LOC) materials with excellent structural and dimensionality tunability by designing the bonding ability of the organic molecules and the stereochemical activity of the Pb lone pair. The introduction of electron-donating substituents on the benzenethiol ligands results in a series of LOCs that transition from 1D to 2D, featuring reduced band gaps (down to 1.7 eV), broadband emission, and strong electron−phonon coupling. We demonstrated a prototypical single crystal photodetector with 2D LOC that showed the dimensionality engineering on the transport property of LOC semiconductors. This study paves the way for further development of the synthesis and optical properties of novel organic−inorganic hybrid 2D materials.

Impact of substituent position on crystal structure and photoconductivity in 1D and 2D lead(ii) benzenethiolate coordination polymers

“…According to previously reported literature, 30,31 the electron density of thiol groups has a significant impact on both the local structure around the Pb( ii ) ions and the coordination numbers, which in turn undergo a (–Pb–S–) n dimensionality change. Specifically, the increased electron density of the thiol group contributes to the transition from the hemidirected to the holodirected mode and increases the coordination number of the Pb–S unit, consequently resulting in the formation of a 2D (–Pb–S–) n layer.…”

“…KGF-34 was prepared using p -HSPhOMe crystallized in the monoclinic space group P 2/ n , consistent with recently reported literature. 30 It contained two crystallographically non-equivalent Pb( ii ) ions (Fig. S2c, ESI†), whose Pb( ii ) centers had a holodirected coordination structure with a [PbS 6 ] octahedron (Fig.…”

“…12,18,29 A recent report also showed that the electron-donating ability of the substituent employed on the HSPh skeleton in the Pb( ii ) S-CPs affects the (–M–S–) n dimensionality. 30 Although the effect of substituent species on the obtained (–M–S–) n networks has been well investigated in the aforementioned study, the correlation between (–M–S–) n dimensionalities and semiconductive properties such as photoconductivity has remained unclear. To further elucidate the aforementioned correlation, a systematic synthesis of S-CPs with the same composition but different (–M–S–) n dimensionalities is required.…”

Optoelectronic insights of lead-free layered halide perovskites

“…The higher values of U eq , and Γ (LO) observed in (OA) 2 SnI 4 in comparison to (PEA) 2 SnI 4 indicate a greater contribution of STE emission in the alkyl chain systems. 59,63–66 This is attributed to the defect states, resulting in the intraband PL, and a subsequent loss of PLQY. Since STE depends on the octahedral tilting in the inorganic layer, the PL intensity also increases with higher out-of-plane octahedral tilting.…”

Heterocyclic Modification Leading to Luminescent 0D Metal Organochalcogenide with Stable X-ray Scintillating Properties

“…Metal organochalcogenides (MOCs) , are an emerging class of hybrid organic–inorganic materials with metal and organochalcogenide units linked by covalent metal–chalcogen bonds. They typically exhibit luminescent properties and excellent chemical stability and can be synthesized at low temperatures in various forms including powders, − microcrystals, − single crystals, , and thin films. − While the research on this materials class was focused mainly on MOCs of coinage metals with [M­(ER)] n formula, where M = Cu­(I), Ag­(I), and Au­(I); E = S, Se, Te; and R is an organic hydrocarbon, the concept of MOCs has recently been extended to other metals including indium, lead, and tin. , …”