Mass spectrometry of nanodiamonds

Abstract

Detonation nanodiamonds (NDs) were studied by time-of-flight mass spectrometry (TOF MS). The formation of singly charged carbon clusters, C R n , with groups of clusters at n ¼ 1-35, n $160-400 and clusters with n $8000 was observed. On applying either high laser energy or ultrasound, the position and intensity of the maxima change and a new group of clusters at n $70-80 is formed. High carbon clusters consist of an even number of carbons while the percentage of odd-numbered clusters is quite low (£5-10%). On increasing the laser energy, the maximum of ionization (at n $200 carbons) is shifted towards the lower m/z values. It is suggested that this is mainly due to the disaggregation of the original NDs. However, the partial destruction of NDs is also possible. The carbon clusters (n $2-35) are partially hydrogenated and the average value of the hydrogenation was 10-30%. Trace impurities in NDs like Li, B, Fe, and others were detected at high laser energy. Several matrices for ionizing NDs were examined and NDs themselves can also be used as a matrix for the ionization of various organic compounds. When NDs were used as a matrix for gold nanoparticles, the formation of various gold carbides Au m C n was detected and their stoichiometry was determined. It was demonstrated that TOF MS can be used advantageously to analyze NDs, characterize their size distribution, aggregation, presence of trace impurities and surface chemistry.

Application of carbon cluster-contained extended plasmas for the high-order harmonic generation of ultrashort pulses

“…[72][73][74][75][76][77] The (4n þ 3) clusters had higher abundance than neighboring ones ( Fig. 1(c), upper panel).…”

Application of Nanodiamonds in Biomolecular Mass Spectrometry

“…For example, Belchova et al [39] has found that the suspension of fine powdered synthetic diamonds in acetonitrile can be used as an effective MALDI matrix which allows very sensitive detection of deoxynivalenol (DON). However, it should be mentioned here that if the laser energy used in MALDI-MS is too high, the singly charged carbon clusters of C n + from ND itself can also be observed in the mass spectra [41]. …”

Large Carbon Cluster Anions Generated by Laser Ablation of Graphene

“…Interestingly, Maruyama observed even-numbered negative cluster ions of C 120 -C 160 by the laser ablation of a Ni -Co graphite disk while pure graphite never generates anion with such large sizes, showing that the metal atoms or clusters can strongly enhance the formation of large caged cluster anions [30]. Houska et al have found weak signals of negatively charged cluster ions up to C 200 or more in the laser desorption ionization process of nanodiamonds [29]. The largest carbon cluster anions previously observed may belong to the work of Jeon and coworkers [31].…”

“…Carbon cluster cations of different sizes and different generation methods or sources have been widely studied [25][26][27][28][29][30][31][32][33][34][35]. Giant carbon clusters as large as C þ 8000 have been observed [29].…”

“…Carbon cluster cations of different sizes and different generation methods or sources have been widely studied [25][26][27][28][29][30][31][32][33][34][35]. Giant carbon clusters as large as C þ 8000 have been observed [29]. The methods of tandem MS, especially collisionally activated dissociation (CAD) MS, have been used for different cluster ions including many endohedral fullerene ions in order to understand their structures and fragmentation behavior [26,27,[36][37][38][39].…”