Large-scale production of graphitic carbon nitride with outstanding nitrogen photofixation ability via a convenient microwave treatment

• Published in: Applied surface science 2016-08, Vol.379, p.309-315
• Main Authors: Ma, Huiqiang, Shi, Zhenyu, Li, Shuang, Liu, Na
• Format: Article
• Language: English
• Subjects: Carbon nitride; Catalysis; Catalysts; g-C3N4; Large-scale production; Microwave; Microwaves; Nitrogen photofixation; Nitrogen vacancy; Photocurrent; Photoelectric effect; Surface chemistry; Vacancies
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.04.085

•Microwave method for synthesizing g-C3N4 with N2 photofixation ability is reported.•Nitrogen vacancies play the important role on the nitrogen photofixation ability.•The present process is a convenient method for large-scale production of g-C3N4. A convenient microwave treatment for synthesizing graphitic carbon nitride (g-C3N4) with outstanding nitrogen photofixation ability under visible light is reported. X-ray diffraction (XRD), N2 adsorption, UV–vis spectroscopy, SEM, N2-TPD, EPR, photoluminescence (PL) and photocurrent measurements were used to characterize the prepared catalysts. The results indicate that microwave treatment can form many irregular pores in as-prepared g-C3N4, which causes the increased surface area and separation rate of electrons and holes. More importantly, microwave treatment causes the formation of many nitrogen vacancies in as-prepared g-C3N4. These nitrogen vacancies not only serve as active sites to adsorb and activate N2 molecules but also promote interfacial charge transfer from catalysts to N2 molecules, thus significantly improving the nitrogen photofixation ability. Moreover, the present process is a convenient method for large-scale production of g-C3N4 which is significantly important for the practical application.