采用沉淀法制备了ZNO纳米粒子，并利用XPS，SPS，ESR和PL等测试技术对样品进行了表征，同时评估了样品在光催化氧化气相η-C7H16中的活性。重点考察了ZNO纳米粒子的表面组成和结构与其光致发光和光催化性能的关系。结果表明：ZNO纳米粒子的粒子尺寸赵小，表面氧空位的量越大，光致发光信号越强，光催化活性越高。说明它们之间必然存在一定的关系，这是因为光致发光信号主要归属于表面氧空位引发的自由和束缚激子发光，而表面氧空位由于易于捕获光生电子，且与吸附氧间存在强列的相互作用，以至于有利于氧化反应的进行。此外，也说明了ZNO纳米粒子的表面态是非常丰富的，主要是由氧空位和氧物种等引起的。

A detailed singlet potential energy surface (PES) of the CHOP system is investigated by means of MP2 and QCISD(T) methods. It is shown that the chainlike isomer HPCO is the most stable species followed by the chainlike HOCP and trans-HCPO, which are also considered as kinetically stable species, and may be experimentally observable. Furthermore, possible molecular dissociation channels are predicated and the result show that the direct dissociation of chainlike HPCO can efficiently proceed prior to almost all isomerizations, but the isomerizations of HOCP and trans-HCPO towards the lowest-lying HPCO are favorable in energy than their direct dissociations.

The reaction mechanism of HF with HOBO is theoretically investigated. At the CCSD(T)/6-11++G(2d,2p)//MP2/6-311++G(d,p) level with zero-point energy correction two low-lying and three high-lying intermediates are found to be kinetically stable and should be isolated in experiments if available and accurate precursors or reactants are used. The primary reaction products of the reaction are suggested to be H2O and FBO, which are predicted to form through two multiple-step reaction channels with 46.64 and 43.88kJ/mol initial reaction barrier, but not via a direct four-center transition state with a 118.39kJ/mol energy barrier, which has been suggested in previous study.

In this paper, pure and La doped TiO2 nanoparticles with different La content were prepared by a sol-gel process using Ti (OC4H9)4 as raw material, and also were characterized by XRD, TG-DTA, TEM, XPS, DRS and Photoluminescence (PL) spectra. We mainly investigated the effects of calcining temperature and La content on the properties and the photocatalytic activity for degrading phenol of as-prepared TiO2 samples, and also discussed the relationships between PL spectra and photocatalytic activity as well as the mechanisms of La doping on TiO2 phase transformation. The results showed that La3+ did not enter into the crystal lattices of TiO2 and was uniformly dispersed onto TiO2 as the form of La2O3 particles with small size, which possibly made La dopant have a great inhibition on TiO2 phase transformation; La dopant did not give rise to a new PL signal, but it could improve the intensity of PL spectra with a appropriate La content, which was possibly attributed to the increase in the content of surface oxygen vacancies and defects after doping La; La doped TiO2 nanoparticles calcined at 600 C exhibited higher photocatalytic activity, indicating that 600 C was an appropriate calcination temperature. The order of photocatalytic activity of La doped TiO2 samples with different La content was as following: 141.54340.54540mol%, which was the same as the order of their PL intensity, namely, the stronger the PL intensity, the higher the photocatalytic activity, demonstrating that there were certain relationships between PL spectra and photocatalytic activity. This could be explained by the points that PL spectra mainly resulted from surface oxygen vacancies and defects during the process of PL, while surface oxygen vacancies and defects could be favorable in capturing the photoinduced electrons during the process of photocatalytic reactions.

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2df)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1, 2A"), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paperalso proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1 from fragments SiN (2P) and PN (1S), which have been well characterized in space, and thus, isomer E1 can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN (2P) + PN(1S)→E1 and the standard enthalpy of formation of isomer E1 are 215.25 and 457.99kJ/mol, respectively, at 298.15K.

In this paper, ZnO nanoparticle photocatalysts were modified by depositing Pd on their surfaces with a photoreduction method. We mainly investigated the modification mechanisms as well as the effects on the photocatalytic activity of ZnO nanoparticles of deposited Pd by means of XPS and SPS (Surface Photovoltage Spectroscopy), and the effects of Pd content on SPS responses were also discussed from the point of the electronic energy level. The results showed that the content of crystal lattice oxygen on the surface of ZnO nanoparticle decreased after an appropriate amount of Pd was deposited, while that of adsorbed oxygen increased, indicating that Pd was mainly deposited on the crystal lattice oxygen. At the same time, the intensity of SPS responses of ZnO nanoparticles remarkably decreased. In addition, the activity of ZnO nanoparticles could be greatly improved by depositing an appropriate amount of Pd in the gas phase photocatalytic oxidation of n-C7H16. Thus, it could be concluded that the increase in surface content of adsorbed oxygen could facilitate the photocatalytic reaction, and there were close relationships between the SPS response and photocatalytic activity, i.e. the weaker the SPS response, the higher the photocatalytic activity, of Pd-deposited ZnO nanoparticles.

Ag-TiO2 catalysts with different Ag contents were prepared via a sol-gel method in the absence of light. Based on the characterizations of XRD, photoluminescence (PL), surface photovoltage spectroscopy (SPS), field-induced surface photovoltage spectroscopy (FISPS), and XPS as well as the evaluation of the photocatalytic activity for degrading rhodamine B(RhB) solutions, it was found that the Ag dopant promoted the phase transformation as well as had an inhibition effect on the growth of anatase crystallite. The PL and SPS intensities were decreased with increasing Ag content, indicating that the Ag dopant could effectively inhibit the recombination of the photoinduced electrons and holes. However, the active sites capturing the photoinduced electrons reduced, while the Ag content exceeded 5mol%. At rather low Ag dopant concentrations, the migration and diffusion of Ag+ ions were predominant, while at rather high Ag dopant concentrations, the migration, diffusion, and reduction of Ag ions simultaneously occurred. The Ag-TiO2 photocatalysts with appropriate content of Ag (Ag species concentration is from about 3 to 5mol%) possessed abundant electron traps so as to be favorable for the separation of the photoinduced electron-hole pairs, which could greatly enhance the activity of the photocatalysts. From the results of FISPS measurements, it could be found that the impurity bands and abundant surface states were introduced into the interfacial layer of TiO2 because of Ag simultaneously doping and depositing, which could improve the absorption capability for visible light of the photocatalysts.

In this paper, we examined the lifetimes of made-in-home ZnO and TiO2 nanoparticles in the gas phase photocatalytic oxidation of n-C7H16 or SO2, and especially investigated the deactivation mechanism by utilizing surface photovoltage spectrum (SPS) and X-Ray photoelectron spectroscopy (XPS) testing techniques and by considering semiconductor chemical properties. The results showed that ZnO could almost be deactivated in the gas phase photocatalytic oxidation of n-C7H16, while TiO2 could keep most of its activity. In the gas phase photocatalytic oxidation of n-C7H16 or SO2, ZnO and TiO2 both could almost be deactivated. The deactivation mainly resulted from semiconductor surface conduction type change from N-type before the photocatalytic reaction to P-type after the deactivation because of the adsorption of the oxidation products such as H2O, CO2 and SO3 on the semiconductor photocatalyst surface. In addition, the activity of the deactivated photocatalyst could be regenerated to a nearly full extent by washing and drying.

The three-dimensional (3D) accessible pore structures (Im3hm space groups) of continuous mesoporous silica SBA-16 thin films have been prepared by a dip-coating technique in nonaqueous media under acidic conditions on indium-tin oxide glass (ITO). The films are oriented with the (111) crystal plane perpendicular to the surface of the film. On one hand, deposition of iron metal into the mesopores of SBA-16 films was achieved by using an electrochemical method. The Fe2O3 nanowire arrays were synthesized. The crystalline structures of porous Fe2O3 nanowires and nanorods were studied via TEM, SEM, and XRD. On the other hand, a small amount of Fe was deposited into the pores of the SBA-16 thin film as a catalyst, and carbon nanotube arrays formed inside the pores of SBA-16 film were fabricated by catalytic decomposition of acetylene at 700℃. The second-order template synthesis method for preparing the ordered array of carbon nanotubes filled with Fe has been used. The carbon nanotubes are very uniform in diameter and length and are aligned vertically with respect to the SBA-16 film.

A singlet potential energy surface (PES) of the [Si,N,C,S]+ system is investigated by means of MP2 and QCISD(T) (single-point) methods. Four linear isomers of [Si,N,C,S]+ system are found to be kinetically stable and should be experimentally observable. The linear isomer SiNCS+ is the thermodynamically most stable, followed by SSiCN+, SSiNC+ and SiCNS+. No cyclic kinetically stable isomers are found. For the isomer SiNCS