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Biobutanol is a green solvent commonly used as gasoline additive. In this study, it is proposed the separation of azeotropic mixtures of butanol and n‐butyl ether (DBE) using ionic liquids (ILs). Suitable anions [AC]− and [H2PO4]− were screened by COSMO‐RS, and the effect of carbon chain length on the separation effect was investigated using quantum chemical calculations. It was found that the anion was primarily responsible for the separation effect, which grew as the carbon chain grew. Molecular dynamics simulations were used to verify the separation performance of the selected ILs. The separation effect of ILs was further verified using vapor–liquid phase equilibrium (VLE) experiments. The extractive distillation process with [PrMIM][AC] as the extractant was investigated to demonstrate the feasibility of ILs for the separation of butanol and DBE. This study analyzes the whole process from microscopic mechanism of action, which provides new ideas for the separation of alcohol‐ether systems. [ABSTRACT FROM AUTHOR]

Progress is made in the advancement of efficient and durable electrocatalysts for the ethylene glycol oxidation reaction (EGOR), which is a critical breakthrough in the conversion of waste plastic into high‐value‐added chemicals. Here, an organic ligand‐modified PdNi bimetallenes (PdNi O‐BMs) catalyst is designed and constructed through the one‐pot method. Benefiting from the frizzy and porous surface structure and inorganic–organic hybrid interface modification, PdNi O‐BMs undergo electrocatalytic reforming of ethylene glycol (EG) derived from polyethylene terephthalate (PET) to form formic acid. The unique structural advantages result in high EGOR performance. Meanwhile, the influence of Ni and organic ligand on the catalyst performance is confirmed through density functional theory calculations. This study reveals an advanced strategy for the synthesis of inorganic–organic hybrid bimetallenes, providing a green and sustainable new approach for PET value‐added transformation. [ABSTRACT FROM AUTHOR]

In this study, a method for separating isopropanol from wastewater using hydrophobic deep eutectic solvents (DESs) synthesized from terpenes and capric acid was proposed. The distribution coefficient and selectivity value of isopropanol (IPA) in the solvents were determined by liquid–liquid extraction experiments, and the extraction performances of the solvents at different molar ratios and temperatures were studied. From the perspective of molecular dynamics simulations, the experimental results were verified by mechanism analysis, the contribution of hydrogen bond donors (HBDs) and hydrogen bond acceptors (HBAs) to the selective separation of isopropanol was explained. The interaction energies, radial distribution functions, normal density distribution, and mean square deviations between the atoms were used to analyze the interactions between the components of the DESs and IPA/water. It was observed that the DESs have a good extraction effect on IPA, which verifies the good application prospects of DESs in wastewater solutions containing alcohol compounds. [ABSTRACT FROM AUTHOR]

In this study, novel molecular structure encoding descriptors composed of feature encoding and one‐hot encoding was developed and then convolutional autoencoder was used to denoise based on the structure of ionic liquids (ILs). It could be used to predict the CO2 solubility in ILs at different temperatures and pressures, when combined with three different machine learning algorithms (multilayer perceptron [MLP], random forest [RF], and support vector machine [SVM]). Statistics of the prediction results show that the newly proposed molecular structure‐based coding has better regression prediction performance than the conventional molecular cheminformatics descriptors. SE‐MLP model with R2 of 0.9873 and mean square error of 0.0007 has the best performance in predicting the CO2 solubility in ILs. In addition, the relationship between features and dissolved CO2 capacity was analyzed through model interpretation to retrieve physical insights for the underlying system. This work provided a new predictive tool for enriching and refining data on CO2 solubility in ILs and for solving phase equilibrium problems. [ABSTRACT FROM AUTHOR]

To reduce emission of nitrogen oxides (NOx) mainly produced from the combustion of nitrogen compounds (NCs) in fossil fuels, it is necessary to decrease the NCs content in fossil fuels. 2‐Pyrrolidone‐based protic ionic liquids (PrILs) with three different anions were synthesized by a one‐step method. The three PrILs were used as extractants to extract pyridine from the model mixtures. The extraction efficiency (EE) was considered to evaluate the extraction performance of the PrILs. The interactions between the PrILs and pyridine were analyzed by σ‐profiles, bond length, and deformation charge density. The results show that the hydrogen bond (H‐bond) formed between pyridine and the three PrILs is the main driving force for the extraction of pyridine from the model mixtures. [ABSTRACT FROM AUTHOR]

BACKGROUND: Economic optimization and dynamic control of the separation process for recovering the ternary mixture of butanone (MEK)/n‐heptane/isopropanol (IPA) from industrial wastewater is a significant topic. In this work, the optimal pressure‐swing distillation (PSD) sequence, heat integration and dynamic control for separating MEK/n‐heptane/IPA were investigated systematically. The optimal separation sequence was determined by combining the minimum total annual cost (TAC) with the residual curves map (RCM). Pressure‐swing distillation with non‐heat integration, partial heat integration or full heat integration was compared in terms of TAC. Dynamic control schemes were designed for optimal processes of two separation sequences with and without heat integration. RESULTS: The results demonstrate that the TAC of optimal PSD with non‐heat integration process can be reduced by 31.11%, whereas the TAC of optimal partial heat integration and full heat integration schemes can be reduced by 39.73% and 40.96%, respectively. The dynamic performance of all control schemes that can resist ±20% feed flow disturbances and composition disturbances are compared with the integral of squared error. CONCLUSION: It is demonstrated that PSD with full integration process (FHIPSD) for separating MEK/n‐heptane/IPA has optimal economic performance, whereas PSD with non‐heat integration process (NTIPSD) has the optimal dynamic performance and robust stability. This work provides a significant reference for industrial separation of MEK/n‐heptane/IPA. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Group III‐nitrides with doping recently attract great interest because of their outstanding ferroelectric and piezoelectric properties. Herein, the spontaneous polarization and piezoelectricity of the wurtzite III‐nitrides (AN, A = Al, Ga, In) with the rare earth element (R = Sc, Y) doping (w‐R0.5A0.5N) are investigated by first‐principles calculations. The polar w‐R0.5A0.5N and nonpolar h‐R0.5A0.5N are stable, which is proved by the elastic constants and phonon band structures. The w‐Sc0.5In0.5N and w‐Y0.5In0.5N can be applied to the ferroelectric field owing to their very small ferroelectric switching barriers (0.149 eV for w‐Sc0.5In0.5N and 0.042 eV for w‐Y0.5In0.5N) with large ferroelectric polarization (1.088 C m−2 for w‐Sc0.5In0.5N and 0.937 C m−2 for w‐Y0.5In0.5N). Furthermore, the w‐Y0.5In0.5N has a large piezoelectric strain constant d33 (14.018 pC N−1) based on the elastic constant C33 softening and the increase of the piezoelectric constant e33, which is three times larger than that of w‐InN (4.191 pC N−1). It is found that the biaxial tensile strain of 2% along in‐place significantly enhances the d33 and e33, which increase to 35.572 pC N−1 and 2.669 C m−2 from 14.018 pC N−1 and 1.700 C m−2 of free w‐Y0.5In0.5N, respectively. [ABSTRACT FROM AUTHOR]

BACKGROUND: The triple‐column extractive distillation (TCED) process for the ternary multi‐azeotropic mixture of N‐hexane/acetone/chloroform is a significant step in waste recovery and purification. Given the common occurrence of feed disturbances in practical industrial production, a feasible dynamic control scheme should effectively resist feed disturbances and ensure product quality, enabling the process to run steadily and safely with a high efficiency. However, it is challenging to design a robust control scheme for separation processes accompanied by side‐stream capability. In this work, dynamic control schemes were designed for four separation processes: conventional and double side‐stream TCED processes with single and double entrainers. A multipoint temperature control scheme, composition‐temperature cascade control scheme and variable ratio control were combined to improve the dynamic performance of the control schemes. RESULTS: The results showed that the control schemes designed for the four extractive distillation processes are highly robust, resisting ±20% feed flow and composition disturbances. A variable ratio control combined with composition‐temperature cascade was found to be vital for double side‐stream TCED schemes. CONCLUSION: The conventional TCED with a single entrainer (CS‐TCED) is an optimal process for N‐hexane/acetone/chloroform separation both from control and economic perspectives. The designed control scheme is simple, low‐cost and easy‐to‐implement with a superior dynamic performance over other separation schemes. This study has a certain theoretical guidance for N‐hexane/acetone/chloroform separation in terms of economic benefits and practical production. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

BACKGROUND 2,2,3,3‐Tetrafluoro‐1‐propanol (TFP) is a benign solvent and widely used in the electronics industry as a cleaning agent. Because water and TFP can form an azeotropic mixture, it consumes energy to separate TFP from its aqueous mixtures using conventional distillation. RESULTS: In this work, the zeolitic imidazolate framework‐8 porous ionic liquid (ZIF‐8‐PIL) and the ionic liquid (IL) N‐butyl pyridinium bis(trifluoromethyl sulfonyl) imide ([Bpy][NTf2]) are used as extractants to extract TFP from its aqueous solution. ZIF‐8‐PIL was synthesized by ZIF‐8 and IL [Bpy][NTf2]. The liquid–liquid equilibrium (LLE) data for the two systems (water + TFP + ZIF‐8‐PIL/IL) were determined at 298.15, 308.15 and 318.15 K under 101.3 kPa. The selectivity (S) and distribution coefficient (D) were examined to assess the extractive performance of ZIF‐8‐PIL and IL. The non‐random two‐liquid (NRTL) model was applied to fit the tie‐line data of the investigated mixtures. CONCLUSION: The results demonstrate that ZIF‐8‐PIL is a suitable extractant to separate TFP with values of S and D greater than unity. The NRTL model has better correlation performance for the ternary systems with root mean square deviation lower than 0.01. The obtained parameters satisfy the minimum state of the mixed Gibbs free energy, which indicated that the model parameters are reliable. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Cresols are valuable phenolic chemicals which are mainly separated from coal tar. The separation of cresols using sustainable technology is of importance for comprehensive utilization of coal tar. In this work, for extracting o‐, m‐, and p‐cresol from the model coal tar, an ionic liquid 1‐ethyl‐3‐methylimidazolium dicyanamide ([Emim][DCA]) was prepared. The influence of ionic liquid dosage, extraction time, and temperature on separating o‐, m‐, and p‐cresol was explored. The extraction efficiency was determined from the experimental results to assess the extraction ability of [Emim][DCA]. With the optimal conditions, o‐, m‐, and p‐cresol were extracted efficiently from the model coal tar and the extraction efficiencies of o‐cresol, m‐cresol, and p‐cresol were up to 99.50%, 99.65%, 98.38%, respectively. In the meantime, the extraction mechanism was determined by calculation of σ‐profile, interaction energy, and electron density. The results showed that [Emim][DCA] and cresols formed the complexes by hydrogen bond. The formation of hydrogen bond was verified by the FTIR spectra, which is helpful for designing the related ionic liquids for recovering the phenolic compounds from coal tar. In addition, the recyclability of the [Emim][DCA] was explored. [ABSTRACT FROM AUTHOR]

BACKGROUND: 2,2,3,3‐tetrafluoro‐1‐propanol (TFP) is a good solvent that is applied in the electronic industry. To recover TFP from its aqueous solution, conventional distillation cannot be adopted because TFP and water can form a minimum azeotrope. RESULTS: In this work, extractive distillation is applied to separate the azeotropic mixture of TFP and water using 1‐ethyl‐3‐methylimidazolium acetate ([EMIM][Ac]) as an entrainer. Based on the analysis of residual curve map, three processes are designed to separate the mixture. Extractive distillation processes (EDP) I and II consist of an extractive column and two flashes, and EDP III consists of an extractive column, a flash, and a stripper. For evaluating the three processes, total annual cost (TAC), CO2 emissions and global energy consumption (GEC) are considered into the objective function. CONCLUSION: The simulated results show that EDP III with an extractive column, a flash, and a stripper can provide better economic and environmental benefits. Water can be obtained from the extractive column with a molar purity of 99.7%. TFP can be separated from the top of the flash and stripper with a molar purity of 99.7%. Furthermore, the control structure with two‐point temperature for EDP III is explored and it shows good responses for the disturbances of feed flow rate and composition. [ABSTRACT FROM AUTHOR]

BACKGROUND Controlling the behavior of processes for the recovery of ethyl acetate and isopropanol from industrial wastewater is a hot topic. In this work, dynamic control structures of the extractive distillation process and heat pump combined with feeding preheating extractive distillation process are researched. The control performance of the proposed control structures is tested by adding feed flow and composition disturbance. In these two processes, two‐point temperature control structure is first used. RESULTS: The results show that this structure can maintain product purity within a reasonable range under disturbance. Furthermore, the composition controller is used to improve control performance. CONCLUSION: The improved structure can effectively meet the requirements of product purity. The heat pump combined with feeding preheating extractive distillation process can use the same control structure as the extraction process and show good controllability. This study has a certain guiding value for the research of chemical dynamic control. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

BACKGROUND Phenol is an important chemical and has many applications in industry. It is mainly produced from coal tar. At present, the commonly used method in industry is caustic washing, which produces a lot of wastewater containing phenolic components, resulting in environmental contamination. Herein, a dual‐functionalized ionic liquid, 1‐hydroxyethyl‐3‐methylimidazolium propionate, was synthesized as a candidate for recovering phenol from a coal tar oil mixture. RESULTS: The performance of the ionic liquid was investigated by extraction experiments with various factors, including phase ratio, contact temperature and contact time. The optimal separation conditions for removing phenol using the ionic liquid were as follows: mDFIL:moil = 1:5; contact temperature, 25 °C; contact time, 30 min. The corresponding removal efficiency was 95.9%. The intermolecular interaction for separating phenol with the ionic liquid was verified to be hydrogen bond attraction using quantum chemical calculations and Fourier transform infrared spectrometry. CONCLUSIONS: The experimental and calculated results showed that 1‐hydroxyethyl‐3‐methylimidazolium propionate was a suitable extractant for removal of phenol from the oil mixture. This provides a reference for the dephenolization process of coal tar in industry. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

An extractive distillation process with two columns and a decanter was proposed to separate ternary toluene‐methanol‐water azeotropic mixtures in a previous study. Based on this process, six processes were established to explore further energy‐efficient schemes to separate the ternary azeotropic system. The optimal parameters of the process were determined in terms of the minimum total annual cost (TAC). The processes with heat integration perform better than those with a side stream or thermal coupling in terms of energy savings and TAC reduction. A process in which both the feed stream of the extractive distillation column and the entrainer recovery column are preheated by the entrainer recycle stream can reduce energy consumption by up to 27.69 % and TAC by 21.36 %. [ABSTRACT FROM AUTHOR]

Summary: Synergistic flame retardancy of tris(1‐methoxy‐2,2,6,6‐tetramethyl‐piperidin‐4‐yl) phosphite (NORPM) and tris(2,4,6‐tribromophenoxy)‐1,3,5‐triazine (TTBPC)/Sb2O3 in high‐impact polystyrene (HIPS) was studied by limiting oxygen index (LOI) determination, UL‐94 test, and cone calorimetry test (CCT). NORPM has an exceptional synergistic effect in HIPS. When the dosage of TTBPC, Sb2O3, and NORPM was 12.8, 3.2, and 0.5 wt% respectively, flame retardant effectivity and synergistic effectivity were 0.424 and 1.15 respectively. Compared with the Flame retardant (FR)‐HIPS containing 16.0 wt% of TTBPC/Sb2O3, the LOI of FR‐HIPS increases from 23.8% to 25.4%, the flame‐retardant rating of FR‐HIPS can be improved from UL 94 V‐2 to V‐0, and the peak heat release rate and total heat release are significantly reduced by combining NORPM in 0.5 wt% concentration. NORPM induces the synergistic effect mainly through the following mechanisms: the active radicals produced by the pyrolysis of NORPM promote the release of bromine radicals from TTBPC and the formation of HBr, which improves the flame retardancy of TTBPC; the above active radicals, together with HBr, quench active free radicals, such as the hydroxyl radical (·OH) and decompose the free radical source, which interrupts the chain reaction during combustion and results in a more efficient flame retardant effect in gaseous phase. [ABSTRACT FROM AUTHOR]

BACKGROUND During the synthesis of isopropyl alcohol (IPA) by hydration of propylene, diisopropyl ether (DIPE) is usually produced as a by‐product. Because IPA and DIPE can form a binary homogeneous azeotrope with the minimum boiling temperature at atmospheric pressure, it is difficult to separate the binary mixture by simple distillation. RESULT: For separating the azeotrope IPA + DIPE, side‐stream extractive distillation column (SSED) and extractive dividing wall column (EDWC) processes with three entrainers [2‐methoxyethanol (2‐MEA), 2‐ethoxyethanol and propylene glycol ethyl ether (PGEE)] were simulated and optimized based on the minimal total annual cost (TAC). Moreover, CO2 emissions of the six sequences were calculated and the impact on the environment evaluated. CONCLUSIONS: The sequence of SSED with PGEE as entrainer can reduce TAC by ≤34.48%, but EDWC with PGEE can offer TAC reduction of ≤52.46%. The results demonstrate that the EDWC sequence with PGEE as entrainer is favourable for separating the binary azeotrope IPA + DIPE. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The semihydrogenation of alkynes into alkenes rather than alkanes is of great importance in the chemical industry. Unfortunately, state‐of‐the‐art heterogeneous catalysts hardly achieve high turnover frequencies (TOFs) simultaneously with almost full conversion, excellent selectivity, and good stability. Here, we used metal–organic frameworks (MOFs) containing Zr metal nodes ("UiO") with tunable wettability and electron‐withdrawing ability as activity accelerators for the semihydrogenation of alkynes catalyzed by sandwiched palladium nanoparticles (Pd NPs). Impressively, the porous hydrophobic UiO support not only leads to an enrichment of phenylacetylene around the Pd NPs but also renders the Pd surfaces more electron‐deficient, which leads to a remarkable catalysis performance, including an exceptionally high TOF of 13835 h−1, 100 % phenylacetylene conversion 93.1 % selectivity towards styrene, and no activity decay after successive catalytic cycles. The strategy of using molecularly tailored supports is universal for boosting the selective semihydrogenation of various terminal and internal alkynes. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is a special type of azeotrope in the chemical industry. The components can form homoazeotrope under atmospheric pressure and azeotropic temperature but show partial miscibility when the temperature decreases. A two‐column/decanter process was presented to separate the mixture. However, the energy consumption and the total annual cost are high. RESULTS: Based on the decanter temperature, the operating parameters of the conventional process and the modified process were optimized to achieve the minimum total annual cost (TAC). Through comparing the two processes, the minimum TAC of the latter one is 14.2% lower than that of the former one when the decanters of the two processes are at 10 °C. A control structure, which can efficiently control the modified process, was also explored and verified. CONCLUSION: For the conventional process and the modified process, the influences of the decanter temperature on the compositions of the layered liquid phases, the total reboiler duty of the columns, and the minimum TAC demonstrated that the decanter temperature has important impacts on energy cost and economy of the two processes. Furthermore, the modified process using two cooling media in combination can further reduce the TAC. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Carbon dioxide and ethane easily form a binary azeotrope under liquefied conditions. An extractive distillation process for the separation of carbon dioxide and ethane using the ionic liquids [bmim][Tf2N], [emim][Tf2N] and [emim][EtSO4] as solvents was explored. The thermodynamic and physical property parameters of each ionic liquid and their thermo‐physical properties that correlated with the experimental data were used to create the ionic liquid components and conduct the process simulation. RESULT: Based on the analysis of its physical properties and relative volatilities, [emim][Tf2N] is the best option as a solvent for extractive distillation separation compared with other ionic liquids. Based on the sensitivity analysis optimization procedure, the minimum total annual cost, carbon dioxide emissions and thermodynamic efficiency were calculated. Compared with traditional extraction distillation, the total annual cost and carbon dioxide emissions of the process using [emim][Tf2N] as a solvent decreased by 62% and 31%, respectively. The thermodynamic efficiency (η) of the electricity generated from hydropower increase by 0.7%. CONCLUSION: The results show that an ionic liquid extractive distillation process using an ionic liquid as the entrainer performs better than a process using traditional organic solvents in terms of economics. Due to the non‐volatility of ionic liquids, a flash tank was used instead of a solvent recovery column to efficiently realize solvent recovery. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND There are three binary azeotropes in the tetrahydrofuran/ethanol/water ternary system at atmospheric pressure. Ternary extractive distillation ( ED) processes were studied to separate the ternary azeotropic mixture using two single component solvents and a mixed solvent as entrainer. RESULT Based on the sequential iterative optimization procedure, the minimal total annual costs ( TACs) of the ternary extractive distillation process using ethylene glycol ( EG), dimethyl sulfoxide ( DMSO), and the mixture of DMSO and EG as entrainer were obtained. Compared with two single component entrainers DMSO and EG, the TAC of the extractive distillation process with mixed entrainer (60 mol% DMSO + 40 mol% EG) decreases by 6.55% and 31.88%, respectively. Furthermore, the reboiler heat duties of two extractive distillation columns ( EDCs) with mixed entrainer were compared with two single component entrainers. CONCLUSION The results show that the optimal ED process using mixed entrainer performs better than that using single component entrainers from the perspective of economics. Moreover, there is a tradeoff between the reboiler heat duties of two EDCs, which can be adjusted by changing the entrainer performance in two EDCs. The use of mixed entrainer enhances the flexibility of the tradeoff because it only needs to change the composition of the mixed entrainer. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND During the synthesis of a liquid crystal monomer, an effluent including tetrahydrofuran( THF) and ethanol is produced. Since THF and ethanol are both important solvents used in the chemical industry, it is necessary to separate the mixture of THF and ethanol for reuse. However, it is hard to effectively separate the mixture via simple distillation because a minimum azeotrope is formed in the binary system. RESULT Extractive distillation and pressure-swing distillation are adopted to separate the mixture and carefully optimized to achieve minimization of the total annual cost ( TAC). A comparison between the two processes is carried out. Pressure-swing distillation is used to separate mixtures of THF and ethanol with various compositions. CONCLUSION The results indicate that pressure-swing distillation performs better than extractive distillation from the standpoint of both economic considerations and product purity. The feasible sequence of high and low pressure of two columns in a pressure-swing distillation is related to the feed composition. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

ABSTRACT Corrosion behavior of carbon steel and aluminum alloy in hydrochloric acid and sulfuric acid solutions was studied using microwave heating and conventional water bath heating method, respectively. The effect of microwave heating on corrosion time was investigated by using weight loss method and the surface morphology of metals was studied by using scanning electron microscope, too. The conclusion that microwave heating is a good method to accelerate corrosion process can be obtained from the test results and surface morphology. Both the mass loss of the metals and the pH of the solutions increase with the microwave power increasing and the immersion time prolonging. The mass loss of the specimens heated by microwave is notably higher than that heated by water bath under the same corrosion time and temperature. For all of the four corrosion systems, the corrosion results obtained using microwave heating at 75 °C lasting 40 h are equivalent to that obtained by using water bath at 55 °C, lasting 168 h, whereas more than 70 h is needed to achieve the same corrosion results by using the water bath at 75 °C. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Location is important for most wireless sensor network applications. A potential localisation method uses a mobile beacon instead of numerous static beacons. This method includes planning a beacon trajectory as a fundamental and interesting problem. Obstacles in practical scenarios often restrict the free locomotion of beacons. This study examines the obstacle‐avoidance path‐planning method, which consists of three stages. First, the network deployment region is partitioned into cells by adaptive cell decomposition, and the corresponding connectivity graph is constructed. Second, a modified max–min ant system algorithm is provided to obtain the approximate shortest global path that covers the connectivity graph. Finally, a sequence of concentric circles of adjustable radii is utilised as the local path within an obstacle‐free cell. We prove that all sensor nodes deployed in obstacle‐free cells can be localised by using the proposed path. Simulation results show that more than 90% of the sensor nodes in the obstacle‐free region can be localised by using the given trajectory. [ABSTRACT FROM AUTHOR]

Polycrystalline BiFeO3 (BFO) film has been fabricated on Pt(111)/Ti/SiO2/Si(001) substrate by a magnetron sputtering method. Both red light of 632.8 nm and purple light of 404 nm have been used to irradiate the sample. It is found that illumination of the sample by the two kinds of lights can induce an increase of the leakage-current density. The increase of current density by purple light is about two orders of magnitude larger than that without irradiation, while an increase of an order of magnitude is produced by red light. Moreover, an enhanced photovoltaic effect has been observed when the sample is illuminated by purple light. The photocurrent at zero bias increases from 0.08 µA cm−2 in the dark to 3.2 µA cm−2 in purple light. The open-circuit voltage is 0.28 V. [ABSTRACT FROM AUTHOR]

An epitaxial SrRuO3 (SRO)/BiFe0.95Mn0.05O3 (BFMO)/SRO heterostructure is fabricated on (001)-SrTiO3 (STO) substrate, in which the SRO film is prepared by magnetron sputtering and the BFMO film is deposited by a sol-gel method. The effect of purple-light irradiation on the SRO/BFMO/SRO capacitor is studied. It is found that the leakage current density of the SRO/BFMO/SRO capacitor, measured at 5 V, increases from 0.013 A/cm2 in the dark to 0.043 A/cm2 in the light. The change of the hysteresis loop of the capacitor upon irradiation can be interpreted by the trapping of photoinduced charges to incur the reorientation of domain and the increase of the leakage current density. In addition, the capacitance versus voltage ( C- V) characteristic of this film is investigated and displays a typical butterfly shape. The above results indicate a potential application of BFMO film for optoelectronic devices. [ABSTRACT FROM AUTHOR]