Pharmaceutical products occurring in freshwater bodies create numerous problems for the water bodies owing to their bio-toxic nature. In order to remove such pharmaceutical pollutants, a novel Er-doped Bi4O5Br2/ g-C3N5 nanocomposite was prepared by one-pot synthesis and applied for the photocatalytic removal process. The Er ions doped on the surface of Bi4O5Br2/ g-C3N5 nanocomposite exhibited 97% degradation of tetracycline in 60 min under visible light irradiation, which is higher than pure g-C3N5 and Bi4O5Br2 photocatalysts. The improved photocatalytic properties are attributed to the outstanding visible light harvesting capacity and quick charge carrier separation efficiency which greatly reduced the recombination rate in the heterojunctions. Based on radical trapping experiments, the •O2 −, h+ and •OH radicals played a prominent role in the photodegradation reactions under visible light. Finally, the ternary Er-doped Bi4O5Br2/ g-C3N5 nanocomposite is effectively recyclable with quite a stable photocatalytic removal rate. This work enables a new perspective on the rational design of rare-earth-based nanocomposites for various pharmaceutical pollutants treatment processes.

The charge transfer (CT) excitation energy calculations of H2N-(CH=CH)3-X and the H2N-H.....H-X structures with the various electron acceptors (-X) were performed with comparing the accuracy of various calculation methods, such as B3LYP, long-range corrected (LC)-BLYP, and EOM-CCSD. Both intra-molecular and inter-molecular systems showed a tendency for CT excitation energy to decrease as the electronic accepting property increases, and LC-BLYP showed the best accuracy in both inter- and intra-molecular CT excitation energy. In this study, it was confirmed that unexpectedly larger range separation parameter(μ) values of LC-BLYP showed better results of CT excitation energy.

[ ](R=Pr, Nd, and Sm) was synthesized and their magnetic properties and charge ordering(CO) transition related with lattice dynamics and oxygen vacancy were systematically investigated. The charge disproportion ation(CD) in (R=Pr,Nd) was in which two kins of iron with valence state and were found with ratio of 2:1. In this charge ordering state a sequence of exists aligned along the [111] direction of the pseudocubic perovskite structure. The charge ordering exist in distorted structure involving hybridization. The disordering phases coexist in distorted structure as temprature in creases that is controlled amount of oxygen vacancy. The magnetic hyperfine fields indicate charge tranfering temperature as it dissapeared drastically.

Ultra-thin films of organic charge transfer complex were prepared on a hydrophilic substrate by Langmuir-Blodgett(LB) technique. In this study, the photoelectric properties of a LB film consisting of (N-docosyl quinolinium)-TCNQ(1:2) complex was investigated. The visible light(λ : 700 nm) of xenon lamp was illuminated on the LB films and light absorptivity and photoconductivity were observed. The photocurrent increased linearly and was saturated at the light intensity of 23 μW/cm2.

Langmuir-Blodgett(LB) 법은 미래의 분자전자소자를 위한 가장 유력한 수단이며, 이러한 분자박막 소자는 그 성질이 분자는 배향에 영향을 박데 되므로 현재 새로운 물질을 이용하여 분자전자소자의 제작에 있어 관심을 모으고 있다. 본 연구에서는 (N-docosyl quinolinium)-TCNQ(1:2) 전하 이동 착물 LB 막의 분자 배향을 UV/vis 편광흡수 스펙트럼과 FT-IR transmission 및 reflection-absorption 스펙트럼의 흡수강도를 비교하여 정량적으로 평가하였다. 그 결과 TCNQ의 transition dipole moment의 각은 약 56~58。 였으며, 알킬 고리의 경사각은 약 11.1~13。였다. 제작된 Z-형 LB 막의 표면은 고압에서 중앙 높이 차가 3~4Å으로 평탄하였다.

In this study, ultra-thin films of (N-docosyl quinolinium)-TCNQ(1:2) complex were prepared on the hydrophilic substrate by Langmuir-Blodgett(LB) technique. The characteristics of π-A isotherms were studied to find optimum conditions of deposition by varying temperature of subphase, compression speed of barrier and amount of spreading solution. Using UV-vis spectra, capacitance and thickness, deposition of LB films was confirmed together with the thickness of the naturally oxidized aluminum film inside a device and dielectric constant of (N-docosyl quinolinium)-TCNQ(1:2) complex. The dielectric constant of LB film was about 4.59~5.58. The electrical properties of (N-docosyl quinolinium)-TCNQ(1:2) complex were investigated at room temperature. The conductivity of this film measured by the direction of either vertical or horizontal axis was found to have a quite different value.

In this research, ultra-thin films of organic charge transfer complex were deposited on to ordinary microscope slide-glass subtrates with a Langmuir-Blodgett technique. π-A isotherm characteristics of these complex were studied in order to find optimum conditions of deposition by varying temperature of subphase, compression speed, and spreading amount. Transfer ratio of these films were studied during the process of deposition. The UV-visible absorbance spectra of LB films were measured to find state of deposition by varing layer number. The observed optimum conditions of surface, pressure, spreading amount, and dipping speed for depositing LB films(Y-type) were 38m/Nm, 150μl and 5mm/min, respectively. Since the tansfer ratio is close to 100%, the monolayer on the subphase seems to be well transferred to the solid substrate. The thickness of the film was well-controlled as the UV-vis absorbance of films were changed linear according to the number of layers.

Octadecyltrimethylammonium-TCNQ(1:1) complex was synthesized by the reaction of LiTCNQ with octadecyltrimethylammonium bromide and the reaction product was identified with FT-IR and UV/Vis spectroscopies. In order to prepare the LB films, π-A isotherm characteristics of octadecyltrimethylammonium-TCNQ(1:1) complex were investigated. The LB films of octadecyltrimethylammonium-TCNQ(1:1) complex were formed on various substrates and the formation of ultrathin films of octadecyltrimethylammonium-TCNQ(1:1) complex was confirmed by using FT-IR and UV-Vis spectroscopies.