Colloid driven low supersaturation crystallization for atomically thin Bismuth halide perovskite

Abstract

It is challenging to grow atomically thin non-van der Waals perovskite due to the strong electronic coupling between adjacent layers. Here, we present a colloid-driven low supersaturation crystallization strategy to grow atomically thin Cs3Bi2Br9. The colloid solution drives low-concentration solute in a supersaturation state, contributing to initial heterogeneous nucleation. Simultaneously, the colloids provide a stable precursor source in the low-concentration solute. The surfactant is absorbed in specific crystal nucleation facet resulting in the anisotropic growth of planar dominance. Ionic perovskite Cs3Bi2Br9 is readily grown from monolayered to six-layered Cs3Bi2Br9 corresponding to thicknesses of 0.7, 1.6, 2.7, 3.6, 4.6 and 5.7 nm. The atomically thin Cs3Bi2Br9 presents layer-dependent nonlinear optical performance and stacking-induced second harmonic generation. This work provides a concept for growing atomically thin halide perovskite with non-van der Waal structures and demonstrates potential application for atomically thin single crystals’ growth with strong electronic coupling between adjacent layers.

Spectroscopic Evidence of Localized Small Polarons in Low-Dimensional Ionic Liquid Lead-Free Hybrid Perovskites

“…However, this peak is diminished in BMIBiBr 4 , which might be due to the overlap in the Raman spectra. A broad peak below 100 cm –1 is associated with the stretching mode of BrBi 2 groups . Surprisingly, APIBiBr 5 shows a prominent peak at 151 cm –1 attributed to Bi–Br connectivity.…”

“…A broad peak below 100 cm −1 is associated with the stretching mode of BrBi 2 groups. 63 Surprisingly, APIBiBr 5 shows a prominent peak at 151 cm −1 attributed to Bi−Br connectivity. The shift of the prominent peak in APIBiBr 5 is due to the difference of Bi−Br connectivity formation.…”

Solid Additive Dual‐Regulates Spectral Response Enabling High‐Performance Semitransparent Organic Solar Cells

“…The booming development of thirdgeneration thin-film solar cells and the diversified requirements in practical applications have necessitated a rational division of the cell market. [1][2][3][4] Organic solar cells (OSCs) have presented significant advantages in flexible electronics and semi-transparent photovoltaics due to their light weight, flexibility, and visual transparency. [5][6][7][8] In recent years, rapid advancements in near-infrared (NIR) materials and device engineering have enabled continuous breakthroughs in power conversion efficiency (PCE) and light utilization efficiency (LUE) of semi-transparent organic solar cells (ST-OSCs), showing great potential for applications in building-integrated photovoltaics and automotive windows.…”

Modulating Adsorption–Redox Sites and Charge Separation of Cs3Bi2Br9–x@AgBr Core–Shell Heterostructure for Selective Toluene Photooxidation

“…For Cs 3 Bi 2 Br 9– x @AgBr, A 1g (out-of-plane vibrational) and E g (in-plane vibrational) resonances of the Bi–Br bond in [BiBr 6 ] 3– octahedron displays a redshift from 166.3 to 164.5 cm –1 and 191.4 to 189.6 cm –1 , compared with pure Cs 3 Bi 2 Br 9 (Figure c) . The shift of binding energies and Raman peaks reveals that the chemical state of Cs, Bi, Br, and Ag has been changed after forming Cs 3 Bi 2 Br 9– x @AgBr heterostructure, implying the strong chemical interaction at the interface …”

“…33 The shift of binding energies and Raman peaks reveals that the chemical state of Cs, Bi, Br, and Ag has been changed after forming Cs 3 Bi 2 Br 9−x @ AgBr heterostructure, implying the strong chemical interaction at the interface. 34 The energy level alignment between Cs 3 Bi 2 Br 9 and AgBr was established using UV−vis diffuse reflectance spectra (UV-vis DRS, Figure 2d), valence band (VB) spectra of XPS (VB-XPS, Figure 2e) and Mott−Schottky tests (Figure S14). The bandgaps (E g ) of Cs 3 Bi 2 Br 9 and AgBr are determined to be 2.56 and 2.37 eV, respectively.…”