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The anionic silicon clusters doped with three boron atoms, B3Sin- (n = 4-10), have been generated by laser vaporization and investigated by anion photoelectron spectroscopy. The vertical detachment energies (VDEs) and adiabatic detachment energies (ADEs) of these anionic clusters are determined. The lowest energy structures of B3Sin- (n = 4-10) clusters are globally searched using genetic algorithm incorporated with density functional theory (DFT) calculations. The photoelectron spectra, VDEs, ADEs of these B3Sin- clusters (n = 4-10) are simulated using B3LYP/6-311+G(d) calculations. Satisfactory agreement is found between theory and experiment. Most of the lowest-energy structures of B3Sin- (n = 4-10) clusters can be derived by using the squashed pentagonal bipyramid structure of B3Si4- as the major building unit. Analyses of natural charge populations show that the boron atoms always possess negative charges, and that the electrons transfer from the 3s orbital of silicon and the 2s orbital of boron to the 2p orbital of boron. The calculated average binding energies, second-order differences of energies, and the HOMO-LUMO gaps show that B3Si6- and B3Si9- clusters have relatively high stability and enhanced chemical inertness. In particular, the B3Si9- cluster with high symmetry (C3v) stands out as an interesting superatom cluster with a magic number of 40 skeletal electrons and a closed-shell electronic configuration of 1S²1P61D102S²2P61F14 for superatom orbitals. [ABSTRACT FROM AUTHOR]

We have successfully obtained a new figure of merit for qualifying fluorine-doped tin oxide (FTO) glass in dye-sensitized solar cells (DSCs) through two equivalent testing methods. These methods are demonstrated and applied to change the equivalent transmittance and sheet resistance of FTO glass even after the glass is assembled in DSCs. By recording the I-V characteristic of a DSC with changed equivalent transmittance and sheet resistance of FTO glass, the dependent relations between the DSC performance (short circuit current density, open circuit voltage, and fill factor) and FTO properties (transmittance and sheet resistance) are found. With these relations, the new figure of merit MTC for FTO glass is successfully defined to be in linearly increasing dependence on the efficiency of DSCs. A series of DSCs with different FTO glasses is prepared to test the effectiveness of MTC and Haacke’s figure of merit [uppercase_phi_synonym]TC, which has been widely used for more than 30 years. The result shows that MTC is proportional to the efficiency of DSCs, while [uppercase_phi_synonym]TC is not. MTC could be very useful as a guideline to greatly simplify the process of optimizing the FTO glass to improve the efficiency of DSCs. [ABSTRACT FROM AUTHOR]