title: Diamond formation by reduction of carbon dioxide at low temperatures.
abstract: This Communication reports a low-temperature diamond synthesis technique, in which diamonds (10-250 mum) can form at a temperature as low as 440 degrees C by reduction of dense CO2 with metallic Na. The X-ray diffraction pattern of a powder sample shows three reflection peaks, indexed with 111, 220, and 311, corresponding unambiguously to cubic diamond. The Raman spectrum of the product exhibits an intense first-order peak at 1332 cm-1, which is the characteristic signature of the cubic diamond, indicating the formation of well-crystallized diamond. Carbon dioxide is a nontoxic low-energy molecule, abundant on earth. This novel reduction method could allow studies of large-size diamond growth using CO2 as the carbon source.
authors.affiliation: Structure Research Laboratory and Department of Materials Science & Engineering, University of Science & Technology of China, Hefei 230026, China.
authors.forename: Zhengsong
authors.initials: Z
authors.lastname: Lou
authors.forename: Qianwang
authors.initials: Q
authors.lastname: Chen
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Yitai
authors.initials: Y
authors.lastname: Qian