Double-photosensitive double-electrode photoelectrochemical sensor as well as preparation method and application thereof

Abstract

The invention discloses a double-photosensitive double-electrode photoelectrochemical sensor as well as a preparation method and application thereof. The sensor comprises a counter electrode and a working electrode, wherein the surface of the counter electrode is modified with three-dimensional graphite phase carbon nitride loaded with gold nanoparticles, the surface of the counter electrode is modified with nitrogen-doped carbon-cuprous oxide shell-core tetrakaidecahedron, and the working electrode is self-assembled with a specific aptamer probe. The preparation method comprises the following steps: modifying three-dimensional graphite phase carbon nitride loaded with gold nanoparticles, a nitrogen-doped carbon-cuprous oxide shell-core tetrakaidecahedron and a specific aptamer probe on conductive glass, and constructing a dual-photosensitive dual-electrode system by the three-dimensional graphite phase carbon nitride, the nitrogen-doped carbon-cuprous oxide shell-core tetrakaidecahedron and the specific aptamer probe. The double-photosensitive double-electrode photoelectrochemical sensor disclosed by the invention has the advantages of high stability, long service life, strong anti-interference capability, wide detection range, low detection limit and the like, can realize specific detection of pollutants (such as antibiotics) in media such as water bodies and organisms, is high in utilization rate, and has very good use value and application prospect.

Description

technical field [0001] The invention belongs to the technical field of biological sensors, and relates to a dual-photosensitive dual-electrode photoelectrochemical sensor and a preparation method and application thereof. Background technique [0002] Chloramphenicol (CAP), a broad-spectrum antibiotic widely used to treat human disease and aquaculture, has been found to be potentially toxic and cause pollution through livestock excreta into rivers. Therefore, it is necessary to develop a low-cost, simple, fast, sensitive and realistic detection method. [0003] Compared with traditional high-performance liquid chromatography, colorimetric, and immunoassays, photoelectrochemical (PEC) sensing methods have shown great advantages. On the basis of high performance, miniaturization and portability have become the development trend of PEC sensors. Therefore, self-powered PEC sensors based on two-electrode stand out because they can eliminate the need for a reference electrode and...

AI Technical Summary

Problems solved by technology

However, most dual-electrode sensors based on photofuel cells (PFC) are anode-type PEC sensors. This type of sensor only pursues the design of photoanode materials, and the cathode does not participate in the photoresponse process. The defect is that the single photoresponse makes the sensor The sensitivity and self-power supply capability are limited, and the photoelectric conversion and detection are placed on the same electrode, which will also reduce the anti-interference ability of the sensor, and there is a shortage of low detection accuracy.

Compared with the anode-type PEC sensor, the cathode-type PEC sensor composed of p-type semiconductors can overcome the disadvantage of poor anti-interference, however, in the existing cathode-type PEC sensors, photoactive materials such as cuprous oxide (Cu 2 O), cuprous bromide (CuBr), etc. to replace the traditional platinum cathode, however, with Cu 2 When O and CuBr are photoactive materials, due to the shortcomings of high charge recombination rate, low photocurrent response and high oxidation possibility, this makes the cathode PEC sensor still have poor stability, short service life, low detection sensitivity, and narrow detection range. Defects such as high detection limit severely restrict the wide application of cathode-type PEC sensors in the detection field

In addition, based on two-dimensional ultrathin g-C 3 N 4 In PEC sensors constructed of nanosheets as n-type inorganic semiconductors, due to g-C 3 N 4 The accumulation and agglomeration of nanosheets are inevitable, which greatly reduces the specific surface area of ​​the photoactive material, which in turn greatly reduces the transfer speed of photogenerated carriers, which is not conducive to obtaining high and stable photocurrent, which also limits the g-C 3 N 4 Application Prospects of Nanosheets in PEC Sensors

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