This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching...This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching solution and the reaction vessel containing the solution and ore was heated at a temperature of 600℃ for 10 minutes. The results of the investigation indicates that the model;P = (e0.7827) S predicts the concentration of phosphorus removed, based on the concentration of sulphur simultaneously removed. It was observed that the validity of the model is rooted in the expression lnP = lnN + lnS where both sides of the expression are approximately equal to 4. The maximum deviation of the model-predicted concentration of removed phosphorus from the corresponding concentration obtained from the experiment was less than 3%. The concentrations of phosphorus removed per unit mass-input of iron oxide ore as obtained from experiment and derived model are 0.8917 and 1.0354 mg/kg g-1 respectively. Similarly, the concentrations of phosphorus removed per unit concentration of removed sulphur as obtained from experiment and derived model are 1.8838 and 2.1874 mg/kg (mg/kg)-1 respectively. This implies that the concentration of phosphorus removed is approximately equal to the concentration of simultaneously removed sulphur during the beneficiation process.展开更多
Self-powered ZnO/perovskite heterostructured ultraviolet （UV） photodetectors （PDs） based on the pyro-phototronic effect have been recently reported as a promising solution for energy-efficient, ultrafast-response,...Self-powered ZnO/perovskite heterostructured ultraviolet （UV） photodetectors （PDs） based on the pyro-phototronic effect have been recently reported as a promising solution for energy-efficient, ultrafast-response, and high-performance UV PDs. In this study, the temperature dependence of the pyro-phototronic effect on the photo-sensing performance of self-powered ZnO/perovskite heterostructured PDs was investigated. The current responses of these PDs to UV light were enhanced by 174.1% at 77 K and 28.7% at 300 K owing to the improved pyro-phototronic effect at low temperatures. The fundamentals of the pyro-phototronic effect were thoroughly studied by analyzing the charge- transfer process and the time constant of the current response of the PDs upon UV illumination. This work presents in-depth understandings about the pyro- phototronic effect on the ZnO/perovskite heterostructure and provides guidance for the design and development of corresponding optoelectronics for ultrafast photo sensing, optothermal detection, and biocompatible optoelectronic probes.展开更多
Cu（In, Ga）Se2 （CIGS）-based materials have gained remarkable attention for thin-film photovoltaic applications due to their high absorption coefficient, tunable bandgap, compositional tolerance, outstanding stabili...Cu（In, Ga）Se2 （CIGS）-based materials have gained remarkable attention for thin-film photovoltaic applications due to their high absorption coefficient, tunable bandgap, compositional tolerance, outstanding stabilities, and high efficiency. A small increase in the efficiency of CIGS solar cells has huge economic impact and practical importance. As such, we fabricated a flexible CIGS solar cell on a mica substrate and demonstrated the enhanced device performance through the piezo- and pyro-phototronic effects based on a ZnO thin film. The device showed enhanced energy conversion efficiency from 13.48% to 14.23% by decreasing the temperature from 31 to 2℃ at a rate of - 0.6℃·s^-1 via the pyro-phototronic effect, and further enhanced from 14.23% to 14.37% via the piezo-phototronic effect by further applying a static compressive strain. A pyro-electric nanogenerator effect was also found to promote the performance of the CIGS solar cell at the beginning of the cooling process. The manipulated energy band of the CIGS/CdS/ZnO heterojunction under the influence of the inner pyroelectric and piezoelectric potentials is believed to contribute to these phenomena. Applying the piezo- and pyro-phototronic effects simultaneously offers a new opportunity for enhancing the output performance of commercial thin film solar cells.展开更多
The Gibbs-like variational methodology is applied to the heterogeneous systems with rigid pyroelectric or pyromagnetic domains. The processes of depolarization/demagnetization are taken into account by assuming the sp...The Gibbs-like variational methodology is applied to the heterogeneous systems with rigid pyroelectric or pyromagnetic domains. The processes of depolarization/demagnetization are taken into account by assuming the spatial mobility of the interfaces. The simplest configuration of flat interface separating rigid pyroelectric half-spaces permits explicit analysis of morphological stability.展开更多
文摘This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching solution and the reaction vessel containing the solution and ore was heated at a temperature of 600℃ for 10 minutes. The results of the investigation indicates that the model;P = (e0.7827) S predicts the concentration of phosphorus removed, based on the concentration of sulphur simultaneously removed. It was observed that the validity of the model is rooted in the expression lnP = lnN + lnS where both sides of the expression are approximately equal to 4. The maximum deviation of the model-predicted concentration of removed phosphorus from the corresponding concentration obtained from the experiment was less than 3%. The concentrations of phosphorus removed per unit mass-input of iron oxide ore as obtained from experiment and derived model are 0.8917 and 1.0354 mg/kg g-1 respectively. Similarly, the concentrations of phosphorus removed per unit concentration of removed sulphur as obtained from experiment and derived model are 1.8838 and 2.1874 mg/kg (mg/kg)-1 respectively. This implies that the concentration of phosphorus removed is approximately equal to the concentration of simultaneously removed sulphur during the beneficiation process.
文摘Self-powered ZnO/perovskite heterostructured ultraviolet （UV） photodetectors （PDs） based on the pyro-phototronic effect have been recently reported as a promising solution for energy-efficient, ultrafast-response, and high-performance UV PDs. In this study, the temperature dependence of the pyro-phototronic effect on the photo-sensing performance of self-powered ZnO/perovskite heterostructured PDs was investigated. The current responses of these PDs to UV light were enhanced by 174.1% at 77 K and 28.7% at 300 K owing to the improved pyro-phototronic effect at low temperatures. The fundamentals of the pyro-phototronic effect were thoroughly studied by analyzing the charge- transfer process and the time constant of the current response of the PDs upon UV illumination. This work presents in-depth understandings about the pyro- phototronic effect on the ZnO/perovskite heterostructure and provides guidance for the design and development of corresponding optoelectronics for ultrafast photo sensing, optothermal detection, and biocompatible optoelectronic probes.
基金This research was supported by the ＂thousands talents＂ program for pioneer researcher and his innovation team, China, National Natural Science Foundation of China （Nos. 11704032, 51432005, 5151101243, and 51561145021）, the National Key R＆D Project from Ministery of Science and Technology （No. 2016YFA0202704）, the National Program for Support of Top-notch Young Professionals, and the China Postdoctoral Science Foundation （No. 2016M600067）.
文摘Cu（In, Ga）Se2 （CIGS）-based materials have gained remarkable attention for thin-film photovoltaic applications due to their high absorption coefficient, tunable bandgap, compositional tolerance, outstanding stabilities, and high efficiency. A small increase in the efficiency of CIGS solar cells has huge economic impact and practical importance. As such, we fabricated a flexible CIGS solar cell on a mica substrate and demonstrated the enhanced device performance through the piezo- and pyro-phototronic effects based on a ZnO thin film. The device showed enhanced energy conversion efficiency from 13.48% to 14.23% by decreasing the temperature from 31 to 2℃ at a rate of - 0.6℃·s^-1 via the pyro-phototronic effect, and further enhanced from 14.23% to 14.37% via the piezo-phototronic effect by further applying a static compressive strain. A pyro-electric nanogenerator effect was also found to promote the performance of the CIGS solar cell at the beginning of the cooling process. The manipulated energy band of the CIGS/CdS/ZnO heterojunction under the influence of the inner pyroelectric and piezoelectric potentials is believed to contribute to these phenomena. Applying the piezo- and pyro-phototronic effects simultaneously offers a new opportunity for enhancing the output performance of commercial thin film solar cells.
文摘The Gibbs-like variational methodology is applied to the heterogeneous systems with rigid pyroelectric or pyromagnetic domains. The processes of depolarization/demagnetization are taken into account by assuming the spatial mobility of the interfaces. The simplest configuration of flat interface separating rigid pyroelectric half-spaces permits explicit analysis of morphological stability.
