Bottom-up growth of homogeneous Moiré superlattices in bismuth oxychloride spiral nanosheets

Abstract

Moiré superlattices (MSLs) are modulated structures produced from homogeneous or heterogeneous 2D layers stacked with a twist angle and/or lattice mismatch. Expanding the range of available materials, methods for fabricating MSL, and realization of unique emergent properties are key challenges. Here we report a facile bottom-up synthesis of homogeneous MSL based on a wide-gap 2D semiconductor, BiOCl, using a one-pot solvothermal approach with robust reproducibility. Unlike previous MSLs usually prepared by directly stacking two monolayers, our BiOCl MSLs are realized in a scalable, direct way through chemical growth of spiral-type nanosheets driven by screw-dislocations. We find emergent properties including large band gap reduction (∼0.6 eV), two-fold increase in carrier lifetime, and strongly enhanced photocatalytic activity. First-principles calculations reveal that such unusual properties can be ascribed to the locally enhanced inter-layer coupling associated with the Moiré potential modulation. Our results demonstrate the promise of MSL materials for chemical and physical functions.

Predicted Optimal Bifunctional Electrocatalysts for the Hydrogen Evolution Reaction and the Oxygen Evolution Reaction Using Chalcogenide Heterostructures Based on Machine Learning Analysis of in Silico Quantum Mechanics Based High Throughput Screening

“…Indeed, Liu et al put forward a new method to synthesize 2D Moiré superlattice. 14 Their study suggests that two-dimensional Moiré superlattice could significantly improve the catalytic activity for a wide range of materials. Indeed several experimental groups [15][16][17] have applied this method, reporting weak but stable coupling of MX2 heterostructures with random rotational angle (0° < θ < 60°), which could help stabilize the overall structure.…”

Band structure engineering through van der Waals heterostructing superlattices of two‐dimensional transition metal dichalcogenides

“…In the real experiment, the weak vdW interaction among the sublayers of heterostructures/superlattices may not be strong enough to form a coherence lattice. The superlattices or heterostructures with the small lattice mismatch may form a periodic Moiré superlattice pattern, 69‐71 which can result in substantial bandgap modulation. Nevertheless, our results give useful guidance for engineering band structure and optical properties in TMDCs out‐of‐plane heterostructing superlattices and may provide a specific database for further studying band gap evolution of TMDCs heterostructing superlattice by using machine learning approach.…”

Alternative Lone‐Pair ns2‐Cation‐Based Semiconductors beyond Lead Halide Perovskites for Optoelectronic Applications

“…f) RhB degradation rate without catalyst (black), using BiOCl bulk (red) and BiOCl MSL nanosheets (green) as catalysts under UV–vis and vis light. [ 183 ] (d–f) Reproduced with permission. Copyright 2019, Nature Publishing Group.…”