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Cadmium telluride (CdTe) thin film photovoltaic devices fabricated in a-line process developed at Colorado State University (CSU) have shown stability during long-term (over a 5 year period) accelerated stress testing. These devices have a copper (Cu) containing back contact. The Cu profile as measured by secondary, ion mass spectrometry. characterization shows, for the maximum stressed device (23,399 h), that there is a significant (two times) change in the concentration of secondary Cu ions in the bulk of the material; however, the Cu concentration gradient at the back of the device has no significant change, and the CdS layer has no significant Cu concentration increase at open-circuit bias and 65[degrees]C temperature conditions. This indicates that with a proper Cd[Cl.sub.2] treatment, Cu can be used to form the back contact for CdTe devices with acceptable stability: These devices have a projected field lifetime of greater than 60 years. [DOI: 10.1115/1.3090820] Keywords: cadmium telluride, multicrystalline, device testing, oxide, surface treatments

In-line manufactured CdTe thin film photovoltaic devices were evaluated for their performance with respect to power conversion efficiency and reliability (stability). A National Renewable Energy Laboratory (NREL) certified power conversion efficiency ([eta]) of 12.44% was measured for one CdTe device. A mean efficiency of 11.4% for 53 devices is shown. Results of reliability studies give a conservative estimate of -1% relative degradation per year in efficiency over a 20-year lifetime for these CdTe devices. [DOI: 10.1115/1.2742393] Keywords: efficiency of CdTe devices, stability, reliability

The development of an efficient and photostable heterostructured photocatalyst has attracted a great deal of attention for the degradation of organic pollutants under visible light. Herein, we have developed a highly efficient graphitic carbon nitride/zinc oxide/iron oxide (g-C3N4/ZnO/Fe2O3) ternary composite photocatalysts that were prepared by a simple and cost-effective calcination method. The crystalline structure, functional groups, morphological and optical properties of the as-prepared g-C3N4/ZnO/Fe2O3 (GZF) ternary composite were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and UV–Vis diffuse-reflectance spectroscopic techniques. The GZF composite reveals enhanced methylene blue (MB) degradation with good photostability of 100% retention rate even after 5 cycles under visible light irradiation. Moreover, GZF composite was degraded 94% of MB after 120 min under visible light irradiation which was almost 6.6- and 3.1-fold higher than individual g-C3N4 (GCN) and g-C3N4/ZnO (GZ). The results suggest that the composites of g-C3N4 with metal oxide under visible light significantly enhance the electron transfer process. [ABSTRACT FROM AUTHOR]

The preparation of gallium(I) solutions, which can be handled using conventional techniques, is reported. The experiments demonstrate that despite occasionally capricious behavior, aqueous solutions of Ga(I) can, with care, be employed in quantitative experiments that require only conventional handling methods.

Pure and barium ion (Ba2+)-doped ammonium di hydrogen ortho phosphate (ADP) crystals were grown from aqueous solution using a slow evaporation process. The presence of Ba2+ ions in the lattice was confirmed by X-ray diffraction (XRD) pattern of the grown crystals, which revealed improved transparency for the compound. Green emission was observed in photoluminescence studies of the grown crystals. The results of Fourier-transform infrared (FTIR) spectroscopy, ultraviolet–visible (UV–visible) spectrum analysis, energy-dispersive X-ray analysis (EDAX) and dielectric studies on the grown crystals were reviewed in detail. A regular slow cooling evaporation method was used to grow the crystals of pure and Ba2+-doped ADP from aqueous solution. [ABSTRACT FROM AUTHOR]

The electrochemical and spectroelectrochemical properties of mononuclear chloro(phthalocyaninato)rhodium(III), ClRhIII, have been determined in the solution phase, at ambient and low temperature. The results showed that a rhodium(II) species, ClRhIIPc, has been formed upon reduction. The RhII species is stable at low temperature, with reversible chemistry, but dimerizes to form a rhodium-rhodium-bonded dinuclear species at ambient temperature.

Initial state-selected and energy resolved channel-specific reaction probabilities, integral cross sections and thermal rate constants of the H(2S) + CH+(X1Σ+) reaction are calculated within the coupled states approximation by a time-dependent wave packet propagation method. The new ab initio global potential energy surface (PES) of the electronic ground state (1 2A′) of the system, recently reported by Li et al. [J. Chem. Phys., 2015, 142, 124302], is employed for this purpose. All partial wave contributions up to the total angular momentum J = 60 are considered to obtain the converged integral reaction cross section up to a collision energy of 1.0 eV. Thermal rate constants are calculated by averaging the reaction cross sections over the Boltzmann distribution of energies and compared with the available theoretical and experimental results for the temperature range 10–1000 K. Investigation of the channel-specific reaction attributes shows that the H abstraction (CH+ destruction) channel is highly favored over the H exchange channel. The effect of rotational and vibrational excitations of the CH+ reagent on the dynamics is also studied. The resonances formed during the course of the reaction are also identified by calculating the transition state spectrum and characterized in terms of the eigenfunctions and lifetimes. More than 260 vibrational levels are obtained and their eigenfunctions are calculated, which are represented in terms of the nodal assignments and the eigenenergies. They reveal both the local and hyperspherical behavior for the bound and quasibound states of the CH2+ complex in the ground 1 2A′ surface. The lifetime analysis of the quasibound states indicates that the CH2+ resonances survive for as long as ∼400 fs at high energies (E∼ 2.0 eV) and are expected to decay faster with further increasing energy. Finally, the type of mechanism for the formation of the product (C+ + H2) is elucidated. [ABSTRACT FROM AUTHOR]

Reduced binary metal oxides of chromium, iron, tungsten and molybdenum were obtained by the addition of hydroxylamine hydrochloride in aqueous solutions of ammonium salts at a fixed pH and maintained by adding hydrochloric acid drops. This method was found to have the potential to lead to the formation of ternary oxides in the presence of other cations. The technique may be applicable to the synthesis of metastable or low temperature phases with interesting physical and structural properties.