Effect of samarium doping on structural, optical and magnetic properties of vertically aligned ZnO nanorod arrays

Samarium doped vertically aligned one dimensional ZnO nanorod（NR） arrays were grown by vapor phase transport（VPT） method through vapor solid（VS） growth process. Influence of different concentrations（0% to 8%） of Sm（all Sm contents in the paper are in mass fraction） on the ZnO NR arrays were investigated by X-ray diffraction（XRD）, field emission scanning electron microscopy（FESEM）, photoluminescence（PL）, Raman spectroscopy and vibrating sample magnetometry（VSM） techniques, respectively. X-ray diffraction studies revealed that the ZnO NR arrays were perfectly oriented along（002） crystallographic orientation with wurtzite crystal structure. Photoluminescence results showed an increase in oxygen vacancies due to increase in Sm doping. M-H curves revealed enhanced ferromagnetic behavior, and the magnetic moment values were 0.45, 0.363, 1.694, 3.613 and 2.197 emu/cm^3 for（0–8%） Sm doped ZnO NR arrays respectively. The curve revealed that paramagnetic behavior was observed for undoped ZnO NR arrays and on increasing the Sm dopant to 4%, paramagnetic switched to ferromagnetic behavior.

Justifying benzoselenadiazole acceptor core as organic semiconductor for stable bulk-heterojunction organic solar cells at ambient temperature

This work describes the utilization of D-A-D type organic semiconductor,4,4’-(benzo[c][1,2,5]selenadiazole-4,7-diyl)bis(N,N-diphenylaniline),denoted as Se-2TPA,containing benzoselenadiazole(BSe)as acceptor core and end-capped with triphenylamine(TPA)donor units as donor materials in solar cells.Superlatively,the attachment of TPA donor moiety in BSe acceptor unit enlarged the conjugated system by extending the p-bonding which effectively tuned the optical and electrochemical properties of Se-2TPA.The bulk heterojunction organic solar cell(BHJ-OSCs)with configuration of ITO/cp-TiO_(2)/Se-2TPA:PC61BM/Au showed power conversion efficiency(PCE)of~4.12% with short circuit current(Jsc)value of~11.28 mA/cm^(2),open circuit voltage(Voc)of~0.775 V and fill factor(FF)of~0.48.PCE significantly increased from~4.12% to~5.29% when 1,8-diiodooctane(DIO)was added as an additive in Se-2TPA:PC61BM blend which associated with less phase separation and improved the charge extraction.The fabricated BHJ-OSCs processed with 3%DIO,ITO/cp-TiO_(2)/Se-2TPA:PC61BM/Au configuration displayed a long-term stability under air condition at an ambient temperature by maintaining~80% PCE for the duration of 30 days.The advantages of easy synthesis,low cost and promising cell performance supported Se-2TPA as successful organic semiconductor for BHJ-OSCs.

Photocatalytic degradation of endocrine disruptor Bisphenol-A in the presence of prepared Ce_xZn_(1-x)O nanocomposites under irradiation of sunlight

Photocatalytic degradation of Bisphenol A （BPA）, a representative endocrine disruptor chemical, was carried out under irradiation of sunlight in the presence of CexZn1-xO nanophotocatalyst. Cerium （Ce） ions were successfully incorporated into the bulk lattice of ZnO by simple co-precipitation process. The CexZn1-xO composite nanostructures exhibited higher photocatalytic efficiency than pure ZnO in the degradation of BPA under sunlight irradiation and nearly complete mineralization of BPA was achieved. The degradation rate was strongly dependent on factors such as the size and structure of catalyst, doping material concentration, BPA concentration, catalyst load, irradiation time and pH levels. This work suggested that the CexZn1-xO assisted photocatalytic degradation is a versatile, economic, environmentally benign and efficient method for BPA removal in the aqueous environment.