Efficient visible-light photocatalysts are essential for energy and environmental sustainability. Many efforts have been devoted to designing diverse heterostructures in the pursuit of high-performance photocatalysts. However, the effect of morphology of the heterostructures on the photocatalytic performance still needs to be further explored. Here, tunable Au-Ag₂S heterostructures were synthesized to investigate the morphology-induced photocatalytic performance by surface-enhanced Raman scattering (SERS) spectroscopy. All the Au-Ag₂S heterostructures possess remarkable visible-light photocatalytic and SERS activity compared with Au or Ag₂S. Moreover, with increasing exposure of the Au component, the Janus heterostructures display better photocatalytic performance than the heterostructures with other morphologies. The possible mechanism is that the axially separated structure enhances the plasmon-induced electron-hole separation and facilitates interfacial charge transfer in the anisotropic heterostructures, owing to a stronger plasmon-enhanced near field. The photocatalytic degradation efficiency of methylene blue by the Au-Ag₂S Janus heterostructures reached 93.9% within only 60 s. The photocatalytic degradation rate is 2.38, 1.53 and 1.48 times higher than that of the core-shell, eccentric core-shell-I and eccentric core-shell-II heterostructures. Our work demonstrates that the morphology of the Au-Ag₂S heterostructures exhibits a significant effect on the visible-light photocatalytic performance, which opens a new pathway toward the design of heterostructures for high-performance photocatalysis.

高效的可见光光催化剂对于能源和环境的可持续发展至关重要。为了追求高性能光催化剂，人们付出了许多努力来设计不同的异质结构。然而，异质结构的形貌对光催化性能的影响仍需进一步探讨。在这里，合成了可调谐的 Au-Ag ₂ S 异质结构，通过表面增强拉曼散射 (SERS) 光谱研究形态诱导的光催化性能。_{与Au或Ag 2}相比，所有Au-Ag ₂ S异质结构都具有显着的可见光光催化和SERS活性此外，随着 Au 组分暴露量的增加，Janus 异质结构比其他形态的异质结构表现出更好的光催化性能。可能的机制是，由于更强的等离子体增强近场，轴向分离结构增强了等离子体引起的电子空穴分离，并促进各向异性异质结构中的界面电荷转移。Au-Ag ₂ S Janus异质结构对亚甲基蓝的光催化降解效率仅在60 s内达到93.9%。光催化降解率比核-壳、偏心核-壳-I和偏心核-壳-II异质结构高2.38、1.53和1.48倍。_{我们的工作表明 Au-Ag 2}的形态S异质结构对可见光光催化性能表现出显着的影响，这为高性能光催化异质结构的设计开辟了一条新途径。