| Nowadays,environmental problems are becoming more and more serious.Therefore,we urgently need to find a new green technology to solve the environmental crisis.In recent years,photocatalysis technology has been widely studied.The combination of pollutant removal and inexhaustible solar energy has been a hot topic in the field of photocatalysis and environment.However,how to improve the utilization of visible light and reduce the electron-hole recombination rate is the main problem in the field of photocatalysis.From the perspective of improving the separation efficiency of photo generated carriers,g-C3N4 and CdS photocatalytic materials were taken as research objects,and the catalysts with special morphology and structure were prepared by soft template method and wet chemical method respectively.And their influence on photocatalytic performance were explored.（1）Three-dimensional network structure assembled by carbon nitride nanowires（3D g-C3N4）was prepared by hydrothermal treatment in the acidic environment provided by nitric acid and calcination,using P123 as the template and dicyandiamide as the precursor of carbon nitride.In this paper,the influence of concentration of nitric acid on the morphology of 3D g-C3N4was investigated.The results showed that when concentration of nitric acid was 2mol/L,3D g-C3N4had the optimal morphology.Moreover,the role of P123 was explored.The results show that the introduction and removal of P123 is not only the key factor to generate 3D network structure,but also increases the specific surface area to 4.6 times of the original and broadens the absorption band edge extends to 800nm.The results showed that when concentration of nitric acid was 2mol/L,3D g-C3N4had the best photocatalytic activity.The rate constant of degradation of phenol was about 5.6times of that of g-C3N4.The improvement of its degradation activity was attributed to the 3D network structure of 3D g-C3N4,which improved the absorption of photons by catalyst,provided more reactive sites,and the residual carbon in the removal of P123 promoted the separation of photogenerated carriers,thus improving the photocatalytic degradation activity.（2）N-CNTs were prepared by two-step method,CdS particles were then filled into the N-CNTs by wet chemistry method to obtain CdS/N-CNTs.In this work,the effect of p H value on the activity of CdS/N-CNTs was investigated.The photocatalytic activity of the catalyst was investigated by the degradation of MB as a probe.The results showed that the CdS/N-CNTs-5 prepared at pH5 had the best photocatalytic degradation activity,and its degradation rate constant was 4.42 times that of CdS.The improvement of its degradation activity was attributed to the special structure of CdS/N-CNTs effectively inhibited the agglomeration of CdS particles,which improved the separation efficiency of photogenerated carriers in CdS. |
