GeSe nanosheets modified surface plasmon resonance sensors for enhancing sensitivity

Abstract

Germanium selenide (GeSe) nanosheets are stable and inexpensive and considered to have a great potential for photovoltaic applications, however we have demonstrated that GeSe nanosheets are also promising for sensing technology, in this paper. By spin-coating the GeSe nanosheets on the surface of noble metal (Au), we have obtained a surface plasmon resonance (SPR) sensor with significantly enhanced sensitivity, and the performance of the sensor is closely related to the thickness of the GeSe film. By detecting different refractive index solutions, we have obtained the optimized sensitivity with 3581.2 nm/RIU (which is nearly 80% improvement compared to traditional SPR sensors) and figure of merit with 14.37 RIU−1. Moreover, the proposed SPR sensor was vastly superior in sensing Pb2+ heavy metal ions after coating it with chitosan and GeSe composite. A maximum sensitivity of 30.38 nm/μg/l has been verified, which is nearly six times better than that of conventional SPR sensor. Our results demonstrated that GeSe nanosheets overlayer with modified SPR sensor has its great potential in heavy metal detection and chemical-specific molecular identification.

Self-organized and self-assembled TiO2 nanosheets and nanobowls on TiO2 nanocavities by electrochemical anodization and their properties

“…The diameter and thickness were about 76 nm and 74 nm, respectively; and the separation distance between nanobowls of around 30 nm. Likewise, our TiO 2 -nb had shorter dimensions (thickness and diameter) than another published in literature [9][10][11][12][13][14][15][16][17]. Additionally, in figures 2(b) and (d), it can be seen the top of the nanocavities (TiO 2 -nc) as some little black circles, like pores, between the spaces of the nanosheets and nanobowls.…”

“…Commonly, nanosheets are synthesized either by exfoliation or hydrothermal and solvothermal processes [1][2][3][4][5][6][7] and they have been applied to Li-ion batteries and supercapacitors for improving the charge and discharge time, and in solar cells [1][2][3][4][5][6][7][8]. In 2019, Zhao et al investigated GeSe nanosheets, and demonstrated that these can be used in surface plasmon resonance sensor by depositing it by spin coating, improving the sensitivity of the sensor in the detection of heavy metals and chemical molecular identification [9]. However, all these fabrication processes are highly expensive and do not allow a precise control of the periodicity of the nanostructures [3][4][5][6][7][8][9].…”

“…In 2019, Zhao et al investigated GeSe nanosheets, and demonstrated that these can be used in surface plasmon resonance sensor by depositing it by spin coating, improving the sensitivity of the sensor in the detection of heavy metals and chemical molecular identification [9]. However, all these fabrication processes are highly expensive and do not allow a precise control of the periodicity of the nanostructures [3][4][5][6][7][8][9].…”

Recent Advances in Surface Plasmon Resonance Optical Sensors for Potential Application in Environmental Monitoring

“…In the following year, Zhao et al deposited a germanium selenide (GeSe)-chitosan composite on top of a gold thin film. (58) Their SPR optical sensor was able to detect Pb 2+ at a concentration of 0.097 nM. Soon after that, Wu et al demonstrated the sensing of Pb 2+ at a much lower concentration.…”

A theoretical design of evanescent wave biosensors based on gate-controlled graphene surface plasmon resonance

“…In their study, the guided-wave SPR structure can enhance the evanescent field at the interface between silicon and cover. Additionally, by spin-coating the GeSe nanosheets on the surface of noble metal (Au), a SPR sensor can significantly enhance its sensitively 26 .…”