本研究成功地以超分子複合物合成melon型態氮化碳(CN600)，並以水熱法反應於氮化碳進一步形成二氧化錫/氮化碳異質結構(CNTO-1*)與同型氮化碳異質結構(CN-ht)。透過TEM影像觀察Pt光沉積於光觸媒表面的位點，得知二氧化錫/氮化碳為具交錯型(stagger)能帶關係的異質結構，且光載子傳輸屬於type-II機制，可有效地分離光載子，進而提升光觸媒的催化活性。此外，由XRD、SSNMR與TEM結果推測，可利用水熱法將melon型態氮化碳轉換為PHI型態而形成同型異質結構。以AM1.5G (100 mW/cm2) 太陽光模擬器作為光源進行產氫反應，CN600 之產率(3162.0 µmol g-1 h-1)相比，CNTO-1* (4166 µmol g-1 h-1)，CN-ht (4323.2 µmol g-1 h-1)的產氫速率均有所提升。而由HMF氧化實驗結果得知，使用CN600作為光觸媒之產物產率為DFF (5.4 %)、FFCA (1.2 %)、FDCA (0.0 %)；CNTO-1*為DFF (12.5 %)、FFCA (2.8 %)、FDCA (0.2 %)；CN-ht為DFF (10.6 %)、FFCA (1.6 %)、FDCA (0.1 %)。本研究合成的兩種異質結構光觸媒皆能有效提升氮化碳之光催化效能。

In this work, supramolecular complex was used to synthesize porous carbon nitride (CN600). SnO2/C3N4 heterostructures (CNTO-1*) and isotype carbon nitride heterostructures (CN-ht) photocatalysts have been further synthesized by hydrothermal method. Based on the distributions of Pt nanoparticles photoreduced on the photocatalysts obtained from TEM images, we figure out that SnO2/C3N4 heterostructures present stagger band alignment and type-II charge transfer mechanism, which could improve charge separation efficiency and photocatalytic performance. Moreover, through 2D-XRD, Solid-State NMR and TEM analysis, we suggest that part of the melon structures in carbon nitrides were converted into poly(heptazine imide) (PHI) structures resulted in isotype heterostructures. Under AM1.5G solar irradiation, the H2 prodrodution rate of CN600 (3162.0 µmol g-1 h-1), CNTO-1* (4166.1 µmol g-1 h-1), and CN-ht (4323.2 µmol g-1 h-1) was increased by 9.1, 12.0 and 12.4 times compared to the conventional carbon nitride PCN (347.9 µmol g-1 h-1). Photocatalytic HMF oxidation over CN600, CNTO-1*, and CN-ht are further investigated in this study. HMF derivatives such as DFF, FFCA, and FDCA are the major products. The total yields for the three products have beenestimated to evaluate the photocatalytic HMF oxidation performances of the three catalysts. The total yields of CN600, CN-ht, and CNTO-1* are 6.6 %, 12.3 %, and 15.5 %, respectively.

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