高光学质量氮化碳薄膜的制备和表征

物 理 化 学 学 报

442 Acta Phys. -Chim. Sin. 2019, 35 (4), 442–450

Received: April 3, 2018; Revised: May 14, 2018; Accepted: May 14, 2018; Published online: May 16, 2018.

*Corresponding author. Email: yuac@https://www.wendangku.net/doc/a516731814.html,; Tel.: +86-10-62515043.

The project was supported by the National Natural Science Foundation of China (21773306).

国家自然科学基金(21773306)资助项目

? Editorial office of Acta Physico-Chimica Sinica

[Article] doi: 10.3866/PKU.WHXB201805163 https://www.wendangku.net/doc/a516731814.html, Preparation and Characterization of Carbon Nitride Film with High Optical Quality

CAO Dandan, Lü Rong, YU Anchi *

Department of Chemistry, Renmin University of China, Beijing 100872, P. R. China.

Abstract: Graphitic carbon nitride (g-CN), as a nonmetal

semiconductor material, has been widely used in various fields, such

as photocatalysis, electrocatalysis, batteries, light-emitting diodes, and

solar cells, owing to its unique electronic and photophysical properties.

However, the application of g-CN in practical devices remains limited

because of the difficulties in fabricating g-CN films of high quality. In

this work, we report a method for preparing a g-CN film with high

optical quality on a substrate of indium tin oxide (ITO) glass and/or

soda lime (NaCa) glass by using melamine as a precursor. First, we

prepared the bulk g-CN from melamine in a muffle furnace via thermal

polymerization. Then, we fabricated the g-CN film on the ITO and/or

NaCa glass substrate with fine-milled, bulk g-CN in a tube furnace

using thermal vapor deposition. With this two-step method, a yellow,

transparent g-CN film with high optical quality was successfully fabricated on both the ITO and/or NaCa glass substrates. To check the quality of the film, we used scanning electron microscopy (SEM) to study the morphology of the fabricated g-CN film on the ITO glass substrate. Both the high-resolution and low-resolution SEM image results show that the obtained g-CN film on the ITO glass substrate had a homogeneous and dense structure without a corrugated surface, illustrating that it had good surface roughness. Then, we investigated the thickness and surface roughness of the g-CN film via atomic force microscopy (AFM). The AFM results show that the thickness of the g-CN film deposited on the ITO glass substrate was around 300 nm and that the surface roughness of the g-CN film deposited on the ITO glass substrate was less than 40 nm. To verify the chemical composition of the obtained g-CN film on the ITO glass substrate, we performed X-ray photoelectron spectroscopy (XPS) and energy-dispersive spectroscopy (EDS) analyses. Both the XPS and EDS results demonstrate that the chemical composition of the g-CN film deposited on the ITO glass substrate was similar to that of bulk g-CN powder. More importantly, we determined the band structure for the g-CN film deposited on the ITO glass substrate by using a combination of steady-state absorption and high-resolution valence band XPS analysis. It was found that the determined band structure for the g-CN film deposited on the ITO glass substrate was close to that of bulk g-CN powder, also indicating that its chemical composition was similar to that of bulk g-CN. Meanwhile, we also found that the prepared g-CN film on the ITO glass substrate effectively degraded methylene blue dye under Xe lamp irradiation, which was similar to the effect of bulk g-CN powder. All analyses performed demonstrate that the two-step method presented in this study could successfully fabricate a g-CN film with high optical quality. In addition, we also analyzed the fluorescence lifetime of the g-CN film deposited on the ITO glass substrate by using a homemade time-correlated single-photon counting apparatus and found that it was much shorter than that of bulk g-CN.

Key Words: Carbon nitride film; Two-step method of vapor deposition; Morphology; Composition; Steady-state

absorption; Fluorescence spectroscopy;

Time-correlated single-photon counting