Rayleigh Instability Triggered Growth of 2D Horizontal Layered and Single‐Phase PtS ₂ Continuous Films for High‐Performance Broadband Photodetection

Abstract Broadband photodetectors (BPD) are widely used in optical spectrometers and imaging chips. Platinum disulfide (PtS ₂ ) exhibits stronger light absorption and thickness‐dependent band gaps from the visible to infrared region with nearly fully occupied d ‐orbital electrons in Pt atoms, which makes it suitable for high‐performance BPD. However, both the irreversible agglomeration and sulfuration disproportionation reaction of Pt films are extremely difficult to control, leading to the main products being PtS ₂ nanoparticles or non‐layered PtS crystals. Herein, a localized interface anchor strategy is reported to control the growth of a large area 2D horizontal layered and continuous PtS ₂ film by precisely regulating the Rayleigh instability of the Pt film and suppressing the thermodynamically favored non‐layered PtS crystal. The Rayleigh instability is well controlled by surface tension, temperature gradient, and stress via tunable heating rate and growth temperature. Large‐area layered PtS ₂ continuous film exhibits excellent broadband photoresponse from 532 to 2200 nm. Interestingly, compared to pure PtS crystals and PtS ₂ /PtS mischcrystals, the photocurrent (I _ph ) significantly increased by ≈7–15 times across different wavelengths, with response (τ _r ) and decay (τ _d ) times noticeably reduced. This work delves into the chemical vapor deposition (CVD) growth mechanism to fabricate large‐area high‐performance 2D continuous films by Rayleigh instability triggered.