Hybrid nanocarbon, comprised of a diamond core and a graphitic shell with a variable sp(2)-/sp(3)-carbon ratio, is controllably obtained through sequential annealing treatment (550-1300 °C) of nanodiamond. The formation of sp(2) carbon increases with annealing temperature and the nanodiamond surface is reconstructed from amorphous into a well-ordered, onion-like carbon structure via an intermediate composite structure--a diamond core covered by a defective, curved graphene outer shell. Direct dehydrogenation of propane shows that the sp(2)-/sp(3)-nanocomposite exhibits superior catalytic performance to that of individual nanodiamond and graphitic nanocarbon. The optimum catalytic activity of the diamond/graphene composite depends on the maximum structural defectiveness and high chemical reactivity of the ketone groups. Ketone-type functional groups anchored on the defects/vacancies are active for propene formation; nevertheless, once the oxygen functional groups are desorbed, the defects/vacancies alone might be active sites responsible for the C-H bond activation of propane.

α-Fetoprotein (AFP) is an important tumor biomarker. In particular, the overexpression of AFP-L3 is associated with hepatocellular carcinoma (HCC). Accordingly, several hospitals have begun to employ the ratio of AFP-L3 to the total AFP level (AFP-L3%) as new diagnostic evidence for HCC owing to its high diagnostic accuracy. However, current methods of detection for AFP and AFP-L3 are time-consuming, require multiple samples, and lack in sensitivity and specificity. Herein, we present a novel concept for the early diagnosis of HCC based on the combination of Raman frequency shift and intensity change, and developed surface-enhanced Raman scattering (SERS)-based immunochips via AFP-L3%. In the first step of the study, the frequency shift of 4-mercaptobenzoic acid (MBA) was applied for the quantitative determination of total AFP based on the AFP and anti-AFP interaction on MBA-modified silver chips. 5,5-Dithiobis(succinimidyl-2-nitrobenzoate) (DSNB)-modified immunogold was then incorporated with AFP-L3 antibodies for sandwich immunoreaction on the chips. As a result, we found that a typical Raman band intensity of DSNB presented an exponential linear relationship with the concentration of AFP-L3. Thus, the AFP-L3% can be calculated according to the concentrations of AFP-L3 and total AFP. The most important advantage of the proposed method is the combination of AFP-L3% and frequency shifts of SERS, which exhibits excellent reproducibility and high accuracy, and significantly simplifies the conventional detection procedure of AFP-L3%. Application of the proposed method with the serum of patients with HCC demonstrated its great potential in early liver cancer diagnosis.

The basicity of the graphitic, pyridine, and pyrrole nitrogen groups on the graphene and single-walled carbon nanotubes is evaluated and compared in terms of both Brønsted base and Lewis base. It turns out that the pyridine group is the most strong basic site, while the graphitic nitrogen does not bring any improvements over the undoped one.

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Optimized structures, with all real frequencies, of superalkali superhalides (Li(3))(+)(SH)(-) (SH=LiF(2), BeF(3), and BF(4)), are obtained, for the first time, at the B3LYP/aug-cc-pVDZ and MP2/aug-cc-pVDZ computational levels. These superalkali superhalides possess three characteristics that are significantly different from normal alkali halides. 1) They have a variety of structures, which come from five bonding mode types: edge-face, edge-edge, face-face, face-edge, and staggered face-edge. We find that the bonding mode type closely correlates with the Li(3)-SH bond energy. 2) The valence electrons on the Li(3) ring are pushed out by the (SH)(-) anion, and become excess electrons, conferring alkalide or electride characteristics on these Li(3)-SH species, depending on the bonding mode type. 3) The highest occupied molecular orbital of each Li(3)-SH species is a doubly occupied delocalized sigma bonding orbital on the Li(3) ring, which indicates its aromaticity. It is noticeable that the maximum negative nucleus-independent chemical shift value (about -10 ppm) moves out from the center of the Li(3) ring, owing to repulsion by the SH(-) anion. We find that these superalkali superhalides are not only complicated "supermolecules", but are also a new type of alkalide or electride, with aromaticity.

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Boron and nitrogen co-doped bilayer graphene (BN-G) and graphene ribbon (BN-GR) as Frustrated Lewis Pair (FLP) catalysts are investigated for hydrogen molecule activation. The nitrogen and boron atoms are separated as they are in different layers of BN-G/GR. Calculations show that this novel FLP catalyst is capable of activating hydrogen molecules. From the Bader charge, Mayer bond order, and the geometrical structures, it can be seen that the hydrogen molecules undergo heterolytic scission and have a late product-like transition state. More interestingly, the active sites are identified as being the carbon atoms around dopants for BN-G. The BN-G/GR catalysts deliver performances comparable to that of the reported FLP catalyst when considering their barrier and reaction energy values. The current work demonstrates the great potential of doped carbon catalysts as FLP catalysts and paves the way to nanostructured carbon catalyst applications in reactions by directly utilizing hydrogen molecules.