Carbon-Based Electronics in Sight? Triazine-based, graphitic carbon nitride as novel two-dimensional semiconductor

However, graphene is not a semiconductor. In the journal Angewandte Chemie, an international team of researchers has now introduced a carbon nitride, a structural analogue of graphene made of carbon and nitrogen that appears to exhibit semiconducting properties.

With a planar, hexagonal, honeycomb structure and freely moving electrons, graphene is, in principle, nothing more than a single-atom layer of graphite. From an electronic point of view, it is a very interesting substance – but it is missing the typical electronic band gap that would make it a semiconductor.

This band gap is the difference in energy between the valence band and the conduction band of the electrons. To be effective, this gap must not be too large, so that it allows electrons to easily move from the valence band to the conduction band when excited.

Various methods have previously been used to provide graphene with such a band gap. An alternative idea is to make a “graphitic carbon nitride”, a material made of carbon and nitrogen, which ought to have properties very similar to graphene.

A team of researchers from the University of Liverpool (UK), the University of Ulm (Germany), the Humboldt University in Berlin (Germany), the Aalto University (Finland), University College London (UK), and the Max Planck Institute of Colloids and Interfaces in Potsdam (Germany) has now been able to make such a material for the first time.

Transmission electron microscopy and scanning force microscopy, as well as X-ray crystallographic examinations proved that the thin crystalline films are a triazine-based, graphitic carbon nitride (TGCN). Triazines are six-membered rings containing three carbon and three nitrogen atoms.

The new material consists of such triazine rings, with additional nitrogen atoms connecting the rings into groups of three to make a two-dimensional layer. The team led by Andrew I. Cooper and Michael J. Bojdys believes that these layers are not fully planar, but are instead slightly wavy.

TGCN thus has a structure similar to that of graphite, however—as hoped—it is a semiconductor. The films produced consisted of between three and several hundred layers of atoms with a direct band gap between 1.6 and 2.0 eV. During the production process, the layers of TGCN are preferentially deposited onto substrates. The crystallization of TGCN on the surface of insulating quartz offers potential for practically relevant applications. This may be a step on the way to the post-silicon era of electronics.

Dr. Michael J. Bojdys initiated this work as a postdoctoral researcher funded by an EPSRC Programme Grant in Liverpool. He is now a junior group leader at the TU Bergakademie Freiberg, working on organic functional materials for energy and storage applications.

Author: Andrew I. Cooper, University of Liverpool (UK), http://www.liv.ac.uk/cooper-group/people/

Title: Triazine-Based, Graphitic Carbon Nitride: a Two-Dimensional Semiconductor

Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201402191

Media Contact

Andrew I. Cooper Angewandte Chemie

All latest news from the category: Materials Sciences

Materials management deals with the research, development, manufacturing and processing of raw and industrial materials. Key aspects here are biological and medical issues, which play an increasingly important role in this field.

innovations-report offers in-depth articles related to the development and application of materials and the structure and properties of new materials.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors