Large‐Area Bi2O2Se Nanosheets With Enhanced Optoelectronic Performance for Flexible Electronics

Why It Matters

Scalable, high‑performance Bi2O2Se nanosheets unlock durable flexible electronics, accelerating market adoption of next‑generation wearables and IoT sensors.

Key Takeaways

• APCVD yields millimeter-scale Bi2O2Si nanosheets
• Carrier mobility reaches 110 cm2/V·s at room temperature
• Mobility exceeds 3700 cm2/V·s at 2.3 K
• Nanosheets survive repeated bending without performance loss
• Growth mechanism clarified via COMSOL adatom diffusion simulations

Pulse Analysis

Flexible electronics are moving from niche prototypes to mainstream products, but the industry still lacks a 2D semiconductor that combines high carrier mobility with mechanical resilience. Bismuth oxyselenide (Bi2O2Se) has emerged as a strong candidate because of its intrinsic high mobility and wide bandgap, yet traditional low‑pressure CVD methods struggle to produce uniform, large‑area films. By shifting to atmospheric‑pressure CVD, the research team bypasses complex vacuum equipment, enabling millimeter‑scale nanosheets that are compatible with roll‑to‑roll manufacturing and large‑substrate processing.

The breakthrough hinges on a deep understanding of adatom diffusion across the substrate, which the authors modeled using COMSOL Multiphysics. Simulations revealed that precise control of temperature gradients and precursor flow rates promotes lateral growth while suppressing nucleation density, resulting in contiguous domains up to 0.4 mm. Compared with graphene or transition‑metal dichalcogenides, Bi2O2Se offers a rare combination of high electron mobility and strong environmental stability, making it attractive for high‑frequency flexible transistors and photodetectors.

Device tests on polymeric substrates confirm that the nanosheets retain their electronic characteristics after thousands of bending cycles, with negligible shifts in threshold voltage or on‑current. The reported room‑temperature mobility of 110 cm² V⁻¹ s⁻¹ rivals that of amorphous oxide semiconductors, while low‑temperature performance exceeds 3700 cm² V⁻¹ s⁻¹, opening pathways for low‑noise, high‑speed flexible circuits. As manufacturers seek materials that can be scaled without sacrificing performance, APCVD‑grown Bi2O2Se is poised to become a cornerstone of next‑generation wearable, medical, and IoT devices.