Surface-enhanced Raman spectroscopy (SERS) based on two-dimensional (2D) materials has attracted great attention over the past decade. Compared with metallic materials, which enhance Raman signals via the surface plasmon effect, 2D materials integrated on silicon substrates are ideal for use in the fabrication of plasmon-free SERS chips, with the advantages of outstanding fluorescence quenching capability, excellent biomolecular compatibility, tunable Fermi levels, and potentially low-cost material preparation. Moreover, recent studies have shown that the limits of detection of 2D-material-based SERS may be comparable with those of metallic substrates, which has aroused significant research interest. In this review, we comprehensively summarize the advances in SERS chips based on 2D materials. As several excellent reviews of graphene-enhanced Raman spectroscopy have been published in the past decade, here, we focus only on 2D materials beyond graphene, i.e., transition metal dichalcogenides, black phosphorus, hexagonal boron nitride, 2D titanium carbide or nitride, and their heterostructures. We hope that this paper can serve as a useful reference for researchers specializing in 2D materials, spectroscopy, and diverse applications related to chemical and biological sensing.

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Hyperuniform disordered solid (HUDS) structures can provide large, uniform, complete, and isotropic light confinement at the nanoscale after precise design. Based on the HUDS structures, in‐plane light confinement for developing photonic integrated circuits is also explored. To improve the performance of HUDS devices, researchers have mainly focused on cell size or cell distribution optimization in HUDS, which suffers from time‐consuming computation or moderate photonic bandgap (PBG) modification. Here, a morphology engineering method is demonstrated to tailor HUDS PBGs and improve HUDS waveguide devices for transverse electric mode. The results show that the Bezier‐curve‐decorated HUDS devices can achieve a maximum of about 75% PBG width increase, 1.5 dB transmittance improvement in a 10 µm long HUDS waveguide, improved quality factors of HUDS‐cladding microring resonators, and device fabrication compatibility with foundry processing. This study opens new avenues for the development of unprecedented devices for exploring light field regulation, nonlinear optics, and sensing.