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Dye-sensitized solar cells (DSSC) are of great scientific significance and application prospect and have attracted wide public concern since they were first reported. The charge recombination in the interface of the DSSC nanocrystalline electrode is thought as a critical issue affecting the DSSC’s performance improvement; however, few systematic studies have been carried out to investigate the effect of the electrolyte additives on the charge recombination suppressing. It is reported that the electrolyte additives can enhance the DSSC short-circuit current. In this work, five typical nitrogen-containing six-element heterocyclic additives used in DSSC were researched theoretically at the B3LYP/6-311G** computational level to elucidate the effects of electrolyte additives on DSSC performance. The five additives were pyridine, pyridazine, pyrimidine, pyrazine and 1,3,5-triazine named as A1–A5, respectively. Their molecular properties, some of which are molecule structures, geometrical configurations, dipole moments, charge distributions, vibrational frequencies and frontier orbitals, were calculated and discussed and their effects on DSSC performance were analyzed theoretically. The results showed an enhanced conjugation effect with the increased number of nitrogen atoms in the conjugated rings of A1–A5 molecules and A1–A5 molecules could bond stably onto the electrode surfaces through the coordination bonding of the N atoms. For the electrolyte additives A1–A5-based DSSC devices, open-circuit voltages and light-to-energy conversion efficiencies increased. This work can be helpful to explain the mechanism of charge recombination suppressing of electrolyte additives for DSSC and offers the potential for future development of high-performance DSSC.

The aggregation behavior of Au atoms and atomic islands on silicone oil surfaces has been systematically investigated by analyzing the evolution of surface coverage. The apparent Au surface coverage increases linearly with the nominal film thickness at low thicknesses and the rate of increase is almost independent of deposition flux. However, as the deposition flux increases, the surface coverage goes up linearly. Further analysis reveals that the deposition flux strongly affects the system free-energy of the island-oil system and therefore the aggregation behavior of the Au atoms and islands.

A new neophysalin, named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A( 1 ), along with three other known neophysalins ( 2 – 4 ) were isolated from the calyxes of Physalis alkekengi L. var. francheti (Mast.) Makino. The structure of 1 was determined by means of 1D and 2D NMR, UV, IR and mass spectra. Compound 1 displayed potent cytotoxicities in vitro against PC-3 and LNCaP cell lines.

We study the growth process and morphology evolution of the ultra-thin Al films deposited on silicone oil surfaces by using atomic force microscopy. Initially, the deposited atoms nucleate and form compact clusters on the liquid surfaces. Then the clusters perform Brownian motion and adhere upon impact, which results in the ramified islands. Finally a continuous film forms as the nominal film thickness d increases. The mean size of the grains in the compact clusters and ramified islands is of the order of 10 1 nm. The ultra-thin Al films exhibit a self-affine surface morphology and therefore the dynamic scaling analysis is performed. It is found that the growth exponent β = 0.23 ± 0.05. In the range d = 0.1–1.0 nm, the roughness exponent α varies from α ≥ 1 to

Ramified iron aggregates are fabricated on silicone oil surface by thermal evaporation method at room temperature and the crossover from ramified aggregates to continuous films is studied by atomic force microscopy. It is shown that the aggregates are composed of numerous granules with the average diameter around 34 nm. The dynamic scaling analysis shows that the growth exponent β= 0.23 ±0.02 and the roughness exponent α evolves from 0.65 to 0.42 with the nominal film thickness, indicating a roughening behavior transfer may exist during the growth process. The physical interpretation for the scaling behavior is presented.

By atomic force microscopy, the surface evolution and kinetic roughening of nanostructured Ag islands on silicone oil surfaces are studied. It is found that the islands are composed of quasi-circular granules with planar size around 50.0 nm, which is approximately independent of nominal thickness d . Our measurement indicates that the geometrical shape of the granules changes from plateau to sphere as d goes up. The dynamic scaling analysis reveal that the roughness exponent α varies between 0.80 and 0.90 as d increases. The average roughness w rms shows power-law relationship with d and the growth exponent β= 0.53 ±0.03 when d ≤4.0 nm. However, w rms deviates obviously from the power-law relationship for the samples with d > 4.0 nm. This anomalous behavior of β is explained by the competition between the shadowing and reemission processes, and then the kinetic evolution and formation mechanism of the islands are presented.

We study the aggregation of silver (Ag) atoms deposited on silicone oil surfaces. It is observed that the apparent Ag coverage of the total area, � , increases linearly with the nominal film thickness h for h< 0:9 nm and its slope k decreases clearly as the deposition flux f increases. Our atomic force microscopy (AFM) observation shows that the average thickness of the atomic aggregates first increases with f , and then approaches a saturation value. Then, the aggregation mechanism of Ag atoms is presented.