Fabrication Of Semiconductor Based Nanomaterials For Photocatalytic Organic Synthesis And Electrochemical Glucose Detection

Semiconductor material has caused great interest in the scientific research area for its special optical and electrical properties. With the rapid development of nanotechnology, the combination of semiconductor material and nanotechnology is more and more closely. Shortening semiconductor to the nanoscale size can significantly improve its properties due to the quantum effect. Therefore, fabrication of semiconductor nanomaterials or modification them in nanoscale to achieve high activity is the main task of the present research in this field.Photocatalytic organic synthesis is one of the important applications of semiconductor materials. In this paper, the porous Cu₂O nanospheres with two different pore sizes were fabricated through template method and etching treatment. The obtained samples were then used as catalysts for photocatalytic aza–Henry reaction. And the results illustrated that when the porous materials were used as photocatalysts, the catalytic activity was affected not only by the intrinsic catalytic properties of the material, but also by the internal diffusion. In addition, the porous Cu₂O nanospheres were loaded on the surface of the glass carbon electrode and used as non-enzymatic biosensor for glucose detection. The result illustrated that the sensor performance was also affected by the mass transfer.The recombination of hole and electron is a major problem that impedes the improvement of photocatalytic activity. In order to overcome the the easily recombination of the photocatalyst, in this paper we fabricated three semiconductor based composite（noble metal/semiconductor, semiconductor/semiconductor, carbon material/semiconductor） and detect their application in photocatalytic organic reaction. The results demonstrate that:（1） The noble metal Au loaded on the surface of Cu₂O to form the Au/Cu₂O composite can effectively improve the catalytic activity.（2） Part of VO43- in Bi VO4 replaced by S2- via the anion exchange process to form the Bi2S3/Bi VO4 heterojunction structure exhibited enhanced catalytic activity than pure Bi VO4.（3） Semiconductor Pb Bi O2 Br was deposited on the RGO to form RGO–Pb Bi O2 Br composite showed better performance than Pb Bi O2 Br alone. Generally speaking, the formation of composite structure can effectively inhibit the recombination of photo-induced electron/hole pair and prolong the life time of the photogenerated holes and electrons, therefore the catalytic activity of the material is highly improved.In summary, several semiconductor nanomaterials were prepared via a variety of methods. The photocatalytic activity of semiconductor was greatly improved by either forming the porous structure or collaborating with assistant catalyst. The obtained semiconductor nanomaterials have great potential in photocatalytic organic synthesis and sensor fabrication.