Synthesis of Pr-doped ZnO nanoparticles: Their structural,optical, and photocatalytic properties

Undoped and praseodymium-doped zinc oxide （Pr-doped ZnO） （with 2.0-mol%-6.0-mol% Pr） nanoparticles as sunlight-driven photocatalysts are synthesized by means of co-precipitation with nitrates followed by thermal annealing. The structure, morphology, and chemical bonding of the photocatalysts are studied by x-ray diffraction （XRD）, scanning electron microscopy （SEM） with energy dispersive x-ray emission spectroscopy （EDS）, x-ray photoelectron spectroscopy （XPS）, and Fourier transform infrared spectroscopy （FTIR）, respectively. The optical properties are studied by photolu- minescence （PL） and UV-vis diffuse reflectance spectroscopy （UV-vis DRS）. We find that Pr doping does not change the crystallinity of ZnO; but it reduces the bandgap slightly, and restrains the recombination of the photogenerated electron-hole pairs. The photocatalytic performance of the photocatalysts is investigated by the photodegradation reaction of 10-mg/L rhodamine B （RhB） solution under simulated sunlight irradiation, showing a degradation rate of 93.75% in ZnO doped with 6.0-mo1% Pr.

Structure, conductivity, and ion emission properties of RbAg4I5 solid electrolyte film prepared by pulsed laser deposition

We fabricated a silver ion emitter based on the solid state electrolyte film of RbAg4 I5 prepared by pulsed laser deposition. The RbAg4 I5 target for PLD process was mechano-chemically synthesized by high-energy ball milling in Ar atmosphere using β-AgI and RbI as raw materials. The ion-conducting properties of RbAg4 I5 were studied by alternating current(AC) impedance spectroscopy and the ionic conductivity at room temperature was estimated 0.21 S/m. The structure, morphology, and elemental composition of the RbAg4 I5 film were investigated. The Ag+ ion-conducting property of the prepared superioni-conductor film was exploited for ion–beam generation. The temperature and accelerating voltage dependences of the ion current were studied. Few nA current was obtained at the temperature of 196?C and the accelerating voltage of 10 kV.

Influence of N2 flow rate on structure and properties of TiBCN films prepared by multi-cathodic arc ion plating and studied with ion beam scattering spectroscopy

TiBCN films were deposited on Si(100) and cemented carbide substrates by using multi-cathodic arc ion plating in C_2H_2 and N_2atmosp^here. Their structure and mechanical properties were studied systematically under different N_2 flow rates. The results showed that the Ti BCN films were adhered well to the substrates. Rutherford backscattering sp^ectroscopy was employed to determine the relative concentration of Ti, B, C and N in the films.The chemical bonding states of the films were explored by X-ray photoelectron sp^ectroscopy, revealing the presence of bonds of Ti N, Ti(C,N), BN, pure B, sp^2C–C and sp^3C–C, which changed with the N_2 flow rate. Ti BCN films contain nanocrystals of Ti N/Ti CN and Ti B_2/Ti(B,C)embedded in an amorphous matrix consisting of amorphous BN and carbon at N_2 flow rate of up to 250 sccm.

Study of doping uniformity of a 200 kV ion implanter by RBS and sheet resistance measurements

The ion implantation uniformity is of vital importance for an ion implanter.In this paper,we report the,uniformity measurement for a large current ion implanter(LC-16 type) by implanting of 190-keV Ar ions into Si to 3×1016 atoms/cm2,followed by Rutherford backscattering spectroscopy(RBS) and sheet resistance measurement providing quantitative information on spatial distribution of dopants.The implant doses obtained from RBS at selected points of the sample give a spatial uniformity of <5%,which are confirmed by the sheet resistance measurement.While sheet resistance is an indirect method for dose evaluation of ion-implanted samples,RBS provides a competent technique for calibration of the ion implantation system.And both measurements show that good uniformity can be achieved for the ion implanter by tuning of the scanning process.

Off-stoichiometry indexation of BiFeO_3 thin film on silicon by Rutherford backscattering spectrometry

BiFeO3 is a multiferroic material with physical properties very sensitive to its stoichiometry.BiFeO3 thin films on silicon substrate are prepared by the sol–gel method combined with layer-by-layer annealing and final annealing schemes.X-ray diffraction and scanning electron microscopy are employed to probe the phase structures and surface morphologies.Using Rutherford backscattering spectrometry to quantify the nonstoichiometries of BiFeO3 thin films annealed at 100？C–650？C.The results indicate that Bi and Fe cations are close to the stoichiometry of BiFeO3,whereas the deficiency of O anions possibly plays a key role in contributing to the leakage current of 10^-5 A/cm^2 in a wide range of applied voltage rather than the ferroelectric polarizations of BiFeO3 thin films annealed at high temperature.