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The changes in Raman spectra of alkali borate glasses with and without Al2O3under high dose of gamma irradiation have been reported. Glasses with composition xK2O.yAl2O3.(1–x–y)B2O3(x = 20 or 30 mol%; y = 0, 10 or 15 mol%), have been prepared by melt-quenching technique. In order to investigate the role of Al2O3in the network of potassium borate glasses, aluminium oxide has been added at the expense of B2O3keeping the amount of alkali same. Gamma irradiation has been performed at a dose rate of 573 Gy.h–1with total absorbed dose of 50 KGy. Samples were characterized before and immediately after irradiation by Raman spectrophotometer. The experimental results clearly indicate a significant change in the structure of borate glass matrix after irradiation, and the dependence of irradiation effects on composition of alkali as well as on aluminium oxide content.

The charge balance in blue-phosphorescent devices was studied using single-carrier devices, and the results show that the transport is highly hole dominant. The effect of the charge balance on the device performance was further demonstrated using different electron-transport materials with different electron mobilities. By optimization of the charge balance, a maximum current efficiency of 60 Cd A−1at a luminance of 500 cd m−2was achieved.

A novel, highly efficient hole injection material based on a conducting polymer polythienothiophene (PTT) doped with poly(perfluoroethylene‐perfluoroethersulfonic acid) (PFFSA) in organic light‐emitting diodes (OLEDs) is demonstrated. Both current–voltage and dark‐injection‐current transient data of hole‐only devices demonstrate high hole‐injection efficiency employing PTT:PFFSA polymers with different organic charge‐transporting materials used in fluorescent and phosphorescent organic light‐emitting diodes. It is further demonstrated that PTT:PFFSA polymer formulations applied as the hole injection layer (HIL) in OLEDs reduce operating voltages and increase brightness significantly. Hole injection from PTT:PFFSA is found to be much more efficient than from typical small molecule HILs such as copper phthalocyanine (CuPc) or polymer HILs such as polyethylene dioxythiophene: polystyrene sulfonate (PEDOT‐PSS). OLED devices employing PTT:PFFSA polymer also demonstrate significantly longer lifetime and more stable operating voltages compared to devices using CuPc.

This paper reports on the effect of varying concentration of erbium (Er3+) on the (70‐x/2) TeO2− (20‐x/2) B2O3−10 ZnO − xEr2O3(where x= 0, 0.5, 1.0, 2.0, 2.5 mol.%) system, fabricated using the conventional melt quenching technique. The impact of Er3+on the structural, physical, and optical properties of these zinc borotellurite glasses is investigated using Fourier transform infrared spectroscopy (FTIR), density measurements and UV–vis spectroscopy. The amorphous nature is confirmed using X‐Ray diffraction. FTIR results reveal that the glass is formed of fundamental borate and tellurite network units. The addition of Er2­O3results in the formation of TeO3at the expense of Te‐O‐Te linkage. The UV–vis spectroscopy results show that Er3+enter the glass matrix showing absorption peaks corresponding to 4f‐4f transitions of trivalent Erbium ions (Er3+) from ground state 4I15/2to the excited states 4F5/2, 4F7/2, 2H11/2, 4S3/2, 4F9/2, 4I9/2, 4I11/2, and 4I13/2. The optical band gap tends to decrease and refractive index increases with the increase in Er3+concentration hence making these materials more efficient for the optical devices such as light emitting devices and image sensors. This paper reports on the effect of varying concentration of erbium (Er3+) on the (70‐x/2) TeO2‐ (20‐x/2) B2O3‐10 ZnO ‐ xEr2O3(where x= 0, 0.5, 1.0, 2.0, 2.5 mol.%) system, fabricated using the conventional melt quenching technique. The impact of Er3+on the structural, physical, and optical properties of these zinc borotellurite glasses is investigated. The amorphous nature is confirmed using X‐ray diffraction.