Graphitic Carbon Nitride-based Thin Films as New Functional Materials

石墨化氮化碳（GCN）是一种非常有趣的物质，因为它只由碳和氮组成，并且对水的分裂表现出很高的光催化活性。到目前为止，GCN材料已被制成粉末并用于这些目的。如果GCN材料以薄膜形式提供，人们可以获得什么好处？考虑到如果聚乙炔只是粉末形式，导电聚合物的科学和技术就不会出现，答案是显而易见的。虽然薄膜有很多优点，但是对GCN薄膜的研究还处于初级阶段。2016年，本课题组报道了通过气相沉积聚合可以获得自支撑的GCN膜样品。GCN薄膜在水蒸气存在下表现出驱动行为。为了通过加入硼来调整GCN薄膜的能带隙，我们小组开发了一种半导体掺杂策略。然而，我们只获得了能带隙大于2.7 eV的材料，这是绝缘体。为了利用可见光或太阳光，一种能隙较小的材料是必要的。本文介绍了采用双区化学气相沉积（CVD）方法合成碳杂化GCN （GCN- c）薄膜的方法。由此得到的GCN-C薄膜具有出色的机械性能，广泛的光吸收，高导电性和高开/关比光电探测器，使其成为电子应用的有前途的材料。这些发现代表了GCN薄膜作为电子材料领域的重大进展。

Graphitic carbon nitride (GCN) is a substance of great interest because it is composed only of carbon and nitrogen and shows a high photocatalytic activity for the splitting of water. So far, GCN materials have been obtained as powders and utilized for these purposes. If GCN materials are available in film form, what benefits one can obtain? The answer is clear considering that the science and technology of conductive polymers would not have emerged if polyacetylene was available only in the powdery form. Although films have many advantages, research on GCN films is still in the early stages. In 2016, our group reported that self-supporting GCN film samples could be obtained by vapor deposition polymerization. The GCN film showed actuation behaviors in the presence of water vapor. To tune the energy band gap of GCN films by incorporating boron, our group has developed a doping strategy for semiconductors. However, we only obtained materials with energy band gaps larger than 2.7 eV, which are insulators. To utilize visible light or sunlight, a material with a smaller energy band gap is necessary. Here I present the synthesis of carbon hybridized GCN (GCN-C) films via a two-zone chemical vapor deposition (CVD) method. The resulting GCN-C films exhibit outstanding mechanical properties, broad optical absorption, high electrical conductivity, and high on/off ratio photodetectors, making them promising materials for electronic applications. These findings represent a significant advancement in the field of GCN thin films as electronic materials.