光促进Pd/g-C_(3)N_(4)催化苯乙烯加氢性能研究

Photo promoted catalytic hydrogenation of styrene over Pd/g-C_(3)N_(4)

采用化学还原法制备了载钯石墨相氮化碳催化剂(Pd/g-C_(3)N_(4)),利用XRD、TEM、XPS及PL等对催化剂进行表征,并以苯乙烯加氢为探针反应考察了其性能。结果表明,载体g-C_(3)N_(4)呈二维堆叠层状结构,活性组分Pd在g-C_(3)N_(4)表面分散均匀,且主要以零价形式存在。PL光谱分析表明,Pd的负载可以促进g-C_(3)N_(4)的光生电子空穴分离,有利于丰富Pd NPs表面的电子云密度。当Pd负载质量分数为0.5%时催化活性最佳,30℃下2 h转化率为80.2%,加入光照后转化率可达99.6%。

Pd/g-C_(3)N_(4) catalysts are prepared through chemical reduction method,and their structure and morphology are characterized by X-ray diffraction(XRD)transmission electron microscope(TEM),X-ray photoelectron spectroscopy(XPS)and photoluminescence spectroscop(PL).The hydrogenation of styrene is used as probe reaction to investigate the performance of the catalysts.Results show that g-C_(3)N_(4) carrier exhibits two-dimensional stacked layer structure,the active component Pd is uniformly dispersed on the surface of g-C_(3)N_(4),and it mainly exists in the form of zero valence.PL spectrum analysis shows that Pd loading can promote the separation of photogenerated electron holes of g-C_(3)N_(4),which is beneficial to enrich the electron cloud density on the surface of Pd NPs.When Pd loading amount is 0.5 wt%,the catalyst exhibits the best activity,over which the conversion of styrene reaches 80.2%at 30℃in 2 h,and will reach 99.6%after illumination.