Study Based On Photoelectric Effect Controlled By The Surface Plasmon Of Gold Nanorods

Photodetectors are important optoelectronic devices.Among them,photoelectric position sensitive detectors based on lateral photovoltaic ef-fect have important application value in photodection.Based on previous research,light absorption performance has an important impact on the core performance of lateral photovoltaic detecting materials.Surface plasmons of gold nanorods(Au NRs)can be used as an effective strategy to improve light absorption due to their unique optical properties,adjustable absorp-tion range,and mature synthesis methods.Based on the surface plasmon characteristics of Au NRs,this paper has creatively carried out research on the Au NRs/Si and Oxide/Au NRs/Si near-infrared light detection structure and the lateral photovoltaic effect(LPE)in them.The specific research content and results are as follows:(1)Synthesis of Au NRs and study of plasmon excitons.Au NRs were synthesized in one step using a silver-induced seedless method.Au NRs with longitudinal surface plasmon resonance(LSPR)peaks at 550-1100nm were obtained by controlling the silver ion content in the growth solu-tion.Moreover,the monodispersity of as-prepared Au NRs were futher im-proved by adding cetyldimethylbenzyl ammonium(HDBAC)to the tradi-tional cetyltrimethylammonium bromide(CTAB)surfactant to form a bi-nary surfactant system in this method.(2)Study on the photoelectric effect in Au NRs/Si structure.The Au NRs/Si photodetection substrates with a wide spectral range,high sen-sitivity,and great selectivity for infrared light was successfully constructed by loading Au NRs on the silicon substrates.LPE was studied in this struc-ture for the first time.Several methods for preparing Au NRs/Si substrates are compared to obtain the best strategy for constructing high performance Au NRs/Si photodetection structures.The as-prepared Au NRs/Si substrates showed high position sensitivity to near-infrared light in the 800-980 nm.Espectially the position sensitivity to 980 nm laser reached 107.22 m V/mm.By changing the aspect ratio of the Au NRs loaded on the substrates,the selectivity of the photodetection substrate to the spectral response can be adjusted.Experiments show that the spectral response sensitivity is regu-lated by the longitudinal surface plasmon resonance of Au NRs.(3)Study on the photoelectric effect in Oxide/Au NRs/Si structure.Zn O and Ti O₂ semiconductor films were deposited on the surface of Au NRs/Si substrates by atomic layer deposition method.The as-prepared Oxide/Au NRs/Si photodetection substrates obtain further improved re-sponse sensitivity and selectivity based on keeping the broad-spectral resonpse advantage of Au NRs/Si.The results show that the Zn O film en-hances the detection sensitivity of the Au NRs/Si structure to the near-infrared wavelength of 800-1100 nm,and the maximum sensitivity of the Zn O/Au NRs/Si structure to the 980 nm laser reaches 177.2 m V/mm.The detection sensitivity of visible light at 400-800 nm wavelength,the maximum sensitivity of Ti O₂/Au NRs/Si structure to laser of 780 nm wavelength reaches 241.54 m V/mm.A thermal electron-mediated mecha-nism was used to explain this unique LPE in Au NRs/Si and Ox-ide/Au NRs/Si structure.