[5] [5] LEI Y, WANG C D, KONG W P, et al. Functionalised B‐Cu@F‐Ag@Au trimetallic nanomaterials with long term stability for rapid and highly sensitive in situ SERS detection of furfural in transformer oil［J］. High Voltage, 2023, 8(2): 293-304.

[6] [6] PRAKASH J, SUN S, SWART H C, et al. Noble metals-TiO2 nanocomposites: From fundamental mechanisms to photocatalysis, surface enhanced Raman scattering and antibacterial applications［J］. Applied Materials Today, 2018, 11: 82-135.

[7] [7] XU D, DUAN L, JIA W, et al. Fabrication of Ag@Fe2O3 hybrid materials as ultrasensitive SERS substrates for the detection of organic dyes and bilirubin in human blood［J］. Microchemical Journal, 2021, 161: 105799.

[8] [8] WU H, SUN X, HOU C, et al. Preparation of quasi-three-dimensional porous Ag and Ag-NiO nanofibrous mats for SERS application［J］. Sensors, 2018, 18(9): 2862.

[9] [9] LUO X, ZHANG S, XIA Z, et al. A combined surface-enhanced Raman spectroscopy (SERS)/colorimetric approach for the sensitive detection of malondialdehyde in biological samples［J］. Analytica Chimica Acta, 2023, 340803.

[10] [10] WANG F, TENG Y, XIA J, et al. Synthesis, structure, magnetism and photocatalysis of α-Fe2O3 nanosnowflakes［J］. RSC advances, 2019, 9(61): 35372-35383.

[11] [11] YANG T, DU L, ZHAI C, et al. Ultrafast response and recovery trimethylamine sensor based on α-Fe2O3 snowflake-like hierarchical architect-ures［J］. Journal of Alloys and Compounds, 2017, 718: 396-404.

[12] [12] YUAN H, LIU Y, FALES A M, et al. Quantitative surface-enhanced resonant Raman scattering multiplexing of biocompatible gold nanostars for in vitro and ex vivo detection［J］. Analytical chemistry, 2013, 85(1): 208-212.

[13] [13] DOMENICI F, BIZZARRI A R, Cannistraro S. SERS-based nanobiosensing for ultrasensitive detection of the p53 tumor suppressor［J］. International journal of nanomedicine, 2011, 2033-2042.

[14] [14] GE H, KONG W P; WANG R, et al. Simple technique of coupling a diode laser into a linear power buildup cavity for Raman gas sensing［J］. Optics Letters, 2023, 48(8): 2186-2189.

[15] [15] WAN F, WANG R, GE H, et al. Optical feedback frequency locking: impact of directly reflected field and responding strategies［J］. Optics Express, 2024. doi:10.1364/OE.520346.

[16] [16] SOMEKAWA T, FUJITA M, IZAWA Y. Furfural analysis in transformer oils using laser Raman spectros-copy［J］. IEEE T. Dielect. El. In., 2015, 22: 229–231.

[17] [17] WAN F, LEI Y, WANG C D, et al. Highly sensitive and reproducible CNTs@Ag modified Flower-Like silver nanoparticles for SERS situ detection of transformer Oil-dissolved furfural［J］. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2022, 273: 121067.