Towards tuning of surface properties by atomic and molecular adsorption on boron-terminated cubic boron nitride (111) surface: A first-principles study

Man-Fai Ng, Mui Kheng Teo, Kok Hwa Lim, Liping Zhou, Michael B. Sullivan and Shuo-Wang Yang

Institute of High Performance Computing, 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Singapore and School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 639798, Singapore

Diamond Relat. Mater., 2008, 17, 2048-2053.

ABSTRACT:

We present a theoretical investigation for the adsorptions of triangular nitrogen trimer radical (N₃) at both the hollow (H3) and fourfold coordinated top (T4) sites on boron-terminated (111) (B(111)) surface of cubic boron nitride (c-BN) in terms of structure, adsorption energy, band structure and work function. For the first time, we explore the H3 and T4 adsorption mechanisms. Moreover, we study the subsequent co-adsorption of N₃, boron and hydrogen atoms on the same adsorption site on the B(111) surface, which will form either pyramid quantum cluster or nearly planar adsorbate. We find that the surface band structure varies substantially depending on the types of terminated surface formed (changing from metallic to semi-conducting), and consequently, the surface work function changes. These results indicate the electronic characteristics of the B(111) surface can be tuned readily using chemical co-adsorption, suggesting its potential for chemical sensing applications.

DOI: 10.1016/j.diamond.2008.07.003