New complexes constructed from in situ nitration of (1H-tetrazol-5-yl)phenol: synthesis, structures and properties

CrystEngComm ◽  
2017 ◽  
Vol 19 (45) ◽  
pp. 6758-6777 ◽  
Author(s):  
Ceng-Ceng Du ◽  
Xin-Fang Wang ◽  
Sheng-Bin Zhou ◽  
Duo-Zhi Wang ◽  
Dianzeng Jia

New complexes based on three precursors via in situ nitration have been prepared. Moreover, the solid state UV-vis spectra and band gap energy of those complexes were investigated, and the luminescent properties (1–3, 7 and 8) and magnetic properties (3–6 and 9) were also discussed.

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1118
Author(s):  
Ibrahim Mustapha Alibe ◽  
Khamirul Amin Matori ◽  
Mohd Hafiz Mohd Zaid ◽  
Salisu Nasir ◽  
Ali Mustapha Alibe ◽  
...  

The contemporary market needs for enhanced solid–state lighting devices has led to an increased demand for the production of willemite based phosphors using low-cost techniques. In this study, Ce3+ doped willemite nanoparticles were fabricated using polymer thermal treatment method. The special effects of the calcination temperatures and the dopant concentration on the structural and optical properties of the material were thoroughly studied. The XRD analysis of the samples treated at 900 °C revealed the development and or materialization of the willemite phase. The increase in the dopant concentration causes an expansion of the lattice owing to the replacement of larger Ce3+ ions for smaller Zn2+ ions. Based on the FESEM and TEM micrographs, the nanoparticles size increases with the increase in the cerium ions. The mean particles sizes were estimated to be 23.61 nm at 1 mol% to 34.02 nm at 5 mol% of the cerium dopant. The optical band gap energy of the doped samples formed at 900 °C decreased precisely by 0.21 eV (i.e., 5.21 to 5.00 eV). The PL analysis of the doped samples exhibits a strong emission at 400 nm which is ascribed to the transition of an electron from localized Ce2f state to the valence band of O2p. The energy level of the Ce3+ ions affects the willemite crystal lattice, thus causing a decrease in the intensity of the green emission at 530 nm and the blue emission at 485 nm. The wide optical band gap energy of the willemite produced is expected to pave the way for exciting innovations in solid–state lighting applications.


ALCHEMY ◽  
2015 ◽  
Vol 4 (1) ◽  
Author(s):  
Khusnan Mustofa ◽  
Nur Aini ◽  
Susi Nurul Khalifah

<p>TiO<sub>2</sub> Anatase activities should be increased from the UV to the visible light photocatalytic activity of TiO<sub>2</sub> to increase anatas. One efforts to optimize TiO<sub>2</sub> anatase activity is doping by using dopant vanadium(V). Synthesis method which is used in this research is a solid reaction method. The steps being taken in this methods include grinding and heating at high temperatures. Dopant concentrations of vanadium(V) which are used in the research was 0.3%, 0.5% and 0.7%. and the characterization used is X-ray diffraction and UV-Vis Diffuse Reflectance Spectroscopy. The result shows that there are a changing of particle size, band gap energy, and absorption of TiO<sub>2</sub> anatas wavelength because of dopan vanadium(V) addition. While TiO<sub>2</sub>’s structure does not change. The crystal sizes of each TiO<sub>2</sub> without doping, V-TiO<sub>2</sub> 0,3%, 0,5% and 0,7% are 53.21 nm, 47.67 nm, 79.65 nm dan 68.99 nm.  Band gap energy of each TiO<sub>2</sub> without doping, V-TiO<sub>2</sub> 0,3%, 0,5% dan 0,7% are 3.309 eV, 3.279 eV, 3.270 eV and 3.259 eV. While wavelength absorption of each TiO<sub>2</sub> without doping, V-TiO<sub>2</sub> 0,3%, 0,5% and 0,7% are 374.9 nm, 378.4 nm, 379.5 nm and 380.8 nm.<em> </em></p><p class="BodyAbstract"> </p><strong><em>Keywords</em>:</strong> <em>Synthesis, titanium dioxide, vanadium(V), solid state method</em>


2019 ◽  
Vol 19 (11) ◽  
pp. 7139-7148 ◽  
Author(s):  
Suresh Sagadevan ◽  
Zaira Zaman Chowdhury ◽  
Mohd. Rafie Bin Johan ◽  
Fauziah Abdul Aziz ◽  
L. Selva Roselin ◽  
...  

In this work, a simple, co-precipitation technique was used to prepare un-doped, pure tin oxide (SnO2). As synthesized SnO2 nanoparticles were doped with Cu2+ ions. Detailed characterization was carried out to observe the crystalline phase, morphological features and chemical constituents with opto-electrical and magnetic properties of the synthesized nanoparticles (NPs). X-ray diffraction analysis showed the existence of crystalline, tetragonal structure of SnO2. Both the sample synthesized here showed different crystalline morphology. The band gap energy (Eg) of the synthesized sample was estimated and it was found to decrease from 3.60 to 3.26 eV. The band gap energy reduced due to increase in Cu2+ dopant amount inside the SnO2 lattice. Optical properties were analyzed using absorption spectra and Photoluminescence (PL) spectra. It was observed that Cu2+ ions incorporated SnO2 NPs exhibited more degradation efficiencies for Rhodamine B (RhB) dye compared to un-doped sample under UV-Visible irradiation. The dielectric characteristics of un-doped, pure and Cu2+ incorporated SnO2 nanoparticles were studied at different frequency region under different temperatures. The ac conductivity and impedance analysis of pure and Cu2+ incorporated SnO2 nanoparticles was also studied. The magnetic properties of the synthesized samples were analysed. Both the sample showed ferromagnetic properties. The research indicated that the Cu2+ ions doping can make the sample a promising candidate for using in the field of optoelectronics, magneto electronics, and microwave devices.


2019 ◽  
Vol 4 (2) ◽  
pp. 101-113
Author(s):  
Restina Bemis ◽  
Nelson ◽  
Ngatijo ◽  
Siti Nurjanah ◽  
Nur'aini Maghviroh

Telah dilakukan sintesis dan karakterisasi ZnO/karbon aktif sebagai fotokatalis untuk mendegradasi rhodamin B. Fotokatalis ZnO/karbon aktif disintesis menggunakan motode solid state menggunakan prekursor Zn(NO3)2.4H2O dan karbon aktif dari tempurung kelapa. Pola difraksi XRD menunjukkan bahwa fotokatalis ZnO/karbon aktif memiliki struktur heksagonal wurzite yang sesuai dengan standar COD- Inorg No. 96-900-4180 dengan kristal berukuran 0,12 µm. Hasil UV-Vis menunjukkan ZnO memiliki nilai energi celah pita (band gap energy, Eg) sebesar 3,12 eV dan hasil SEM menunjukkan morfologi permukaan berbentuk tidak beraturan dan mangalami mengalami aglomerasi. Analisis EDS pada ZnO dan ZnO/karbon aktif memberikan persentase massa elemen Zn= 59,4%; O=   38,6%   dan   Zn=  66,9%;  O=23,6%;  C=7,8%.  Hasil      uji   aktivitas  fotokatalitik menunjukkan bahwa kondisi optimum degradasi rhodamin B 10 ppm memerlukan 200 mg fotokatalis ZnO/karbon aktif dan waktu radiasi sinar UV selama 90 menit. Fotokatalis ZnO/karbon aktif efektif dalam mendegradasi zat warna rhodamin B pada kondisi optimumnya dengan  persentase  degradasi  sebesar  86,84%.  Dari  data  analisis  LC-MS menunjukkan terjadi degradasi molekul rhodamin B (m/z= 442,88) membentuk senyawa intermediet  dengan  perbandingan  rasio  massa  dan  muatan  sebesar  387,30;  359,01; 331,12; 132,79 dan 117,03 m/z.


2020 ◽  
Vol 92 (2) ◽  
pp. 20402
Author(s):  
Kaoutar Benthami ◽  
Mai ME. Barakat ◽  
Samir A. Nouh

Nanocomposite (NCP) films of polycarbonate-polybutylene terephthalate (PC-PBT) blend as a host material to Cr2O3 and CdS nanoparticles (NPs) were fabricated by both thermolysis and casting techniques. Samples from the PC-PBT/Cr2O3 and PC-PBT/CdS NCPs were irradiated using different doses (20–110 kGy) of γ radiation. The induced modifications in the optical properties of the γ irradiated NCPs have been studied as a function of γ dose using UV Vis spectroscopy and CIE color difference method. Optical dielectric loss and Tauc's model were used to estimate the optical band gaps of the NCP films and to identify the types of electronic transition. The value of optical band gap energy of PC-PBT/Cr2O3 NCP was reduced from 3.23 to 3.06 upon γ irradiation up to 110 kGy, while it decreased from 4.26 to 4.14 eV for PC-PBT/CdS NCP, indicating the growth of disordered phase in both NCPs. This was accompanied by a rise in the refractive index for both the PC-PBT/Cr2O3 and PC-PBT/CdS NCP films, leading to an enhancement in their isotropic nature. The Cr2O3 NPs were found to be more effective in changing the band gap energy and refractive index due to the presence of excess oxygen atoms that help with the oxygen atoms of the carbonyl group in increasing the chance of covalent bonds formation between the NPs and the PC-PBT blend. Moreover, the color intensity, ΔE has been computed; results show that both the two synthesized NCPs have a response to color alteration by γ irradiation, but the PC-PBT/Cr2O3 has a more response since the values of ΔE achieved a significant color difference >5 which is an acceptable match in commercial reproduction on printing presses. According to the resulting enhancement in the optical characteristics of the developed NCPs, they can be a suitable candidate as activate materials in optoelectronic devices, or shielding sheets for solar cells.


2015 ◽  
Vol 7 (3) ◽  
pp. 1923-1930
Author(s):  
Austine Amukayia Mulama ◽  
Julius Mwakondo Mwabora ◽  
Andrew Odhiambo Oduor ◽  
Cosmas Mulwa Muiva ◽  
Boniface Muthoka ◽  
...  

 Selenium-based chalcogenides are useful in telecommunication devices like infrared optics and threshold switching devices. The investigated system of Ge5Se95-xZnx (0.0 ≤ x ≤ 4 at.%) has been prepared from high purity constituent elements. Thin films from the bulk material were deposited by vacuum thermal evaporation. Optical absorbance measurements have been performed on the as-deposited thin films using transmission spectra. The allowed optical transition was found to be indirect and the corresponding band gap energy determined. The variation of optical band gap energy with the average coordination number has also been investigated based on the chemical bonding between the constituents and the rigidity behaviour of the system’s network.


2021 ◽  
Author(s):  
Zichen Shen ◽  
Huanzhen Liu ◽  
Xuemei Jia ◽  
Qiaofeng Han ◽  
Huiping Bi

Bismuth-rich oxyhalides are promising photocatalysts due to their special layered structure and adjustable band gap energy. In this work, a series of bismuth oxyiodides were fabricated by grinding-assistant calcining in...


2011 ◽  
Vol 83 (24) ◽  
Author(s):  
O. Demichel ◽  
V. Calvo ◽  
P. Noé ◽  
B. Salem ◽  
P.-F. Fazzini ◽  
...  

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