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Most current flexible electronic devices are based on petroleum materials that are difficult to degrade. The exploration of sustainable and eco-friendly materials has become a major focus in both the scientific and industrial communities. In this study, BC-Zn-BIM (bacterial cellulose-Zn-benzimidazole), a novel composite electrode material based on biodegradable BC was developed. Here, BC acted as a conductive medium involved in the conductive behavior of the composite material. We've explored the charge transport mechanisms of BC-Zn-BIM by density functional theory (DFT) calculations, and applied it in the electrochemical detection of Bisphenol A (BPA). The results indicated that the oxygen-containing groups in BC and the nitrogen-containing heterocycles in BIM have a tendency to lose electrons, whereas zinc ions actively acquire electrons from these groups. This process promoted charge transfer within BC-Zn-BIM and endowed it with semiconductor-like properties, enhancing the electrocatalytic reaction of BPA. The detection limit of the electrochemical biosensor was 12 nM, and the sample recovery was 95.1%105.6%. This study clarified the mechanism of the higher electrical properties achieved in Zn-BIM complex grown in-situ on dielectric BC. This will further promote the development of low-cost, environmentally friendly flexible electronic devices. [Display omitted] • A new type of conductive BC-Zn-BIM (bacterial cellulose-Zn-benzimidazole) material was prepared. • The BC-Zn-BIM complex constructed a continuous charge transfer pathway. • The charge transport mechanism of BC-Zn-BIM was studied using DFT (density functional theory) calculations. [ABSTRACT FROM AUTHOR]

Transition metal cobalt doped BiOBr (Co-BOB) was successfully synthesized by using hydrothermal method. The optimized Co-BOB achieved a remarkable rhodamine B degradation rate of 97 % in 30 min under visible light irradiation when initial concentration was 80 mg·L−1. Satisfactory removal efficiency was also observed under ambient sunlight irradiation and various water conditions. The cobalt doping strategy induced abundant surface oxygen vacancies formation (43.22 %) and resulted in an increasing exposure of {110} facets. The photosensitization and photocatalytic activities of Co-BOB significantly enhanced comparing with that of pure BiOBr. The synergy of Co doping and oxygen vacancies also induced the formation of a new band structure in Co-BOB. The synergistic effect promoted the efficient separation of photogenerated electrons and holes. By combining with density functional theory calculation, the RhB photocatalytic degradation mechanism by Co-BOB was proposed. [Display omitted] • Trace amounts of cobalt contributed to the formation of abundant surface oxygen vacancies in BOB. • The photocatalytic degradation efficiency of Co-BOB under visible light irradiation achieved 97 % for 80 mg·L−1 RhB solution. • DFT calculation indicated that the mid-energy levels of Co-BOB were induced by cobalt atoms and oxygen vacancies. [ABSTRACT FROM AUTHOR]

• The structural properties of methyl acetate–methanol–IL mixtures are studied. • Distinct interaction complexes between methyl acetate–methanol/IL were identified. • The introduction of the IL led to species transformation in the mixtures. • The molecular mechanism responsible for the azeotropy breaking by IL was unveiled. The ionic liquid (IL) has demonstrated promising potential as an entrainer in efficiently separating the methyl acetate−methanol azeotropic mixture using extractive distillation. However, comprehending the fundamental mechanism responsible for azeotropism vanished by an IL entrainer is crucial for its large-scale applications. This study aims to explore the microstructure characteristics of the 1-ethyl-3-metfighylimidazolium thiocyanate ([EMIM][SCN])–methyl acetate−methanol systems using FTIR and DFT calculations. The focus is on understanding the fundamental reasons behind azeotrope breaking facilitated by the IL entrainer. Initially, the v (aromatic C–H) region of the imidazolium cation was analyzed to evaluate the interaction strength between the entrainer and methyl acetate/methanol. The results indicated stronger interactions between [EMIM][SCN] and methanol. As a consequence of this variation in interaction strength, the relative vapor pressure of the two constituents was impacted, ultimately resulting in the disturbance of the azeotrope. Subsequently, the v (C=O) region of methyl acetate was utilized to detect interaction complexes in various systems, assisted by excess spectra. Various interaction species, including methyl acetate–methanol/2methanol and methyl acetate–ion cluster/ion pair/cation were found. Notably, when the mole fraction of IL exceeded 0.087, the IL effectively disrupted the interaction complex between methyl acetate and methanol, thereby eliminating azeotropy in the methyl acetate–methanol system. [Display omitted] The methyl acetate−methanol interaction complex broken apart by the ionic liquid−methyl acetate interaction complexes [ABSTRACT FROM AUTHOR]

• The structural properties of methyl acetate–methanol–IL mixtures are studied. • Distinct interaction complexes between methyl acetate–methanol/IL were identified. • The introduction of the IL led to species transformation in the mixtures. • The molecular mechanism responsible for the azeotropy breaking by IL was unveiled. The ionic liquid (IL) has demonstrated promising potential as an entrainer in efficiently separating the methyl acetate−methanol azeotropic mixture using extractive distillation. However, comprehending the fundamental mechanism responsible for azeotropism vanished by an IL entrainer is crucial for its large-scale applications. This study aims to explore the microstructure characteristics of the 1-ethyl-3-metfighylimidazolium thiocyanate ([EMIM][SCN])–methyl acetate−methanol systems using FTIR and DFT calculations. The focus is on understanding the fundamental reasons behind azeotrope breaking facilitated by the IL entrainer. Initially, the v (aromatic C–H) region of the imidazolium cation was analyzed to evaluate the interaction strength between the entrainer and methyl acetate/methanol. The results indicated stronger interactions between [EMIM][SCN] and methanol. As a consequence of this variation in interaction strength, the relative vapor pressure of the two constituents was impacted, ultimately resulting in the disturbance of the azeotrope. Subsequently, the v (C=O) region of methyl acetate was utilized to detect interaction complexes in various systems, assisted by excess spectra. Various interaction species, including methyl acetate–methanol/2methanol and methyl acetate–ion cluster/ion pair/cation were found. Notably, when the mole fraction of IL exceeded 0.087, the IL effectively disrupted the interaction complex between methyl acetate and methanol, thereby eliminating azeotropy in the methyl acetate–methanol system. [Display omitted] The methyl acetate−methanol interaction complex broken apart by the ionic liquid−methyl acetate interaction complexes [ABSTRACT FROM AUTHOR]

The multifield-coupled manufacturing process has garnered considerable interest from a multitude of scholars and researchers, owing to its superior efficacy in enhancing material properties. Yet, a comprehensive elucidation of the coupled mechanism among externally assisted fields remains elusive, thereby potentially constraining the universal adoption of this process. Considering the applications of multifield-coupled technology in manufacturing processes and existing expositions of multifield function mechanisms, we collate the salient applications of multifield-coupled methods, encompassing electric-ultrasonic vibration assisted field (EUVAF), electric-magnetic compound field (EMCF), and electric-magnetic-ultrasonic vibration compound field (EMUCF). Moreover, we rigorously analyze the mechanisms of these three multifield-coupled processes, placing particular emphasis on aspects such as quantum mechanics wave, electron migration, vacancy mobility, dislocation evolution, and precipitated phase, among others. In tandem, the multifield mechanisms' dynamics and thermodynamics perspectives are explicated, along with the merits and demerits of multifield applications. A pioneering perspective of the multifield is explored from the vantage point of energy theory of thermodynamics. We postulate that future explorations in the multifield-coupled domain might underscore the relevance of Heisenberg's uncertainty principle (HUP), the density functional theory (DFT), and the maximization of multifield-coupled benefits. The manuscript delineates potential multifield applications in the future, which comprise electric-ultrasonic additive technology, electropulsing-ultrasonic vibration assisted rolling process, electropulsing-ultrasonic vibration assisted micro-forging process; electropulsing-ultrasonic vibration-assisted drawing process; and ultrasonic vibration-magnetic pulse sorting technology. The prospective advancements of multifield equipment are projected. [ABSTRACT FROM AUTHOR]

• The fundamental mechanism of azeotrope breaking in DMC–ethanol by an IL was uncovered. • FTIR and DFT were combined to analyse the v (aromatic C–H) and v (O–D) regions. • Interaction strength and complexes between different components were revealed. • The interactions of IL–ethanol were stronger and changed the mixture's volatility. • The IL can break the DMC–ethanol complex (cause of azeotropy). Owing to their outstanding properties, ionic liquids (ILs) have been increasingly applied as entrainers to separate alcohol azeotrope systems in extractive distillation. Fundamental studies on the mechanism of azeotrope breaking are essential for the better use of ILs; however, they are not often reported. To reveal the intrinsic cause of azeotrope breaking by an IL entrainer, on this work, the microstructure features of IL–azeotrope systems were investigated using FTIR and DFT calculations. 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][Tf 2 N]) and the azeotrope systems dimethyl carbonate (DMC) and ethanol were selected. The v (aromatic C–H) region of the imidazolium cation was analysed first to distinguish the relative interaction strength between the IL and ethanol/DMC. The v (O–D) region of ethanol was applied to identify the interaction complexes in different mixtures and estimate the relative interaction strength between ethanol and the IL/DMC. Combined with DFT calculations, it was found that interactions between [BMIM][Tf 2 N] and ethanol were stronger than those between [BMIM][Tf 2 N] and DMC, which could influence the relative vapour pressure of the two constituents, thus breaking the azeotrope. The interactions between ethanol and the IL were stronger than those between ethanol and DMC. Thus, the addition of the IL could break the interaction complex of DMC–ethanol, which is the cause of azeotropy in the DMC–ethanol system. When x (IL) was larger than 0.170, the entire DMC–ethanol complex disappeared accompanied with the eliminated of the azeotrope. [ABSTRACT FROM AUTHOR]

[Display omitted] • The reduction of V4+ to V2+ in deactivated VS 2 can be restrained by B-doping. • We used in situ tests to trace the evolution of V and analyze the NRR process. • In situ engineering B-S-V bond facilitates the electron transfer from V to B. VS 2 is a promising NRR electrocatalyst, however, it remains a challenge to stabilize the V4+ active sites to retain the activity of VS 2 under long term electrolysis. Herein, we report the synthesis of boron doped VS 2 (B-VS 2) as an advanced NRR electrocatalyst with stable V4+ for efficient catalytic performance. X-ray absorption spectroscopy (XAS) proves that B-doping virtually induces the formation of B-S-V bonding configuration in the resultant B-VS 2. Importantly, we used quasi in situ X-ray photoelectron spectrometer (XPS), in situ Raman and in situ Fourier transform infrared (FTIR) spectra to dynamically trace the evolution of V valence state and analyze the accumulation of N N and N N species during NRR process. The significantly enhanced NRR performance of B-VS 2 is attributed to the in situ engineering B-S-V bond which can stabilize V4+ active sites by manipulating electron redistribution. Density functional theory calculations show that the newly formed B-S-V bond facilitates the electron transfer from V atoms to B atoms, in which S atoms act as the electron transfer bridges, thus generating electron-rich B sites and electron-deficient V sites. Such an electron redistribution substantially stabilizes the V4+ active sites, which suppresses the reduction of V4+ to V2+ at extremely low overpotential. This work not only provides powerful guidelines for improving the NRR performance of VS 2 based electrocatalysts, but also offers a deep understanding of relationship between the valence state of active sites and the catalytic activity. [ABSTRACT FROM AUTHOR]

The disposal of the Cr containing tannery sludge has become a serious environmental problem in China, which has attracted increasing attention. However, experimental and theoretical research is still needed. We developed a feasible route to synergistic immobilization the Cr in tannery sludge into the spinel-based phases by addition of ZnO and TiO 2. ZnO and Cr3+ can form stable spinel-based phase, and TiO 2 can suppress the formation of Cr6+. The significantly synergistic effect between ZnO and TiO 2 promoted the immobilization of Cr in tannery sludge and reduce the leaching of the chromium in the annealed sludge. The oxidation of Cr3+ to Cr6+ in the presence of alkaline substances has been elucidated by density functional theory, and it is revealed that the electrons from the Cr-d orbit jump to the Ca-d and directly transform into the O 2. [Display omitted] • Chromium element is fixed in the spinel crystal lattice by loading of ZnO. • The Cr3+ oxidation process with the alkaline matter is retarded by ZnO and TiO 2. • The oxidation mechanism of Cr 2 O 3 with CaO is elucidated by computation. [ABSTRACT FROM AUTHOR]

The disposal of the Cr containing tannery sludge has become a serious environmental problem in China, which has attracted increasing attention. However, experimental and theoretical research is still needed. We developed a feasible route to synergistic immobilization the Cr in tannery sludge into the spinel-based phases by addition of ZnO and TiO 2. ZnO and Cr3+ can form stable spinel-based phase, and TiO 2 can suppress the formation of Cr6+. The significantly synergistic effect between ZnO and TiO 2 promoted the immobilization of Cr in tannery sludge and reduce the leaching of the chromium in the annealed sludge. The oxidation of Cr3+ to Cr6+ in the presence of alkaline substances has been elucidated by density functional theory, and it is revealed that the electrons from the Cr-d orbit jump to the Ca-d and directly transform into the O 2. [Display omitted] • Chromium element is fixed in the spinel crystal lattice by loading of ZnO. • The Cr3+ oxidation process with the alkaline matter is retarded by ZnO and TiO 2. • The oxidation mechanism of Cr 2 O 3 with CaO is elucidated by computation. [ABSTRACT FROM AUTHOR]

Structurally distorted MnO 2 is obtained via a simple Ni-doping treatment. The substantially accelerated electronic and ionic transfer kinetics contribute to an enhanced Na+ storage performance for supercapacitors applications. [Display omitted] • Structure distorted MnO 2 was prepared via Ni doping. • The Ni-MnO 2 shows high specific capacity and excellent rate performance. • Ni-MnO 2 exhibits delocalized electron and accelerated ionic transport kinetics. Manganese dioxide is a typical electrode material for supercapacitor due to its high theoretical capacitance and good environmental compatibility. However, the development of MnO 2 as electrode is limited by inferior conductivity, sluggish ionic transfer kinetics and poor cycling stability. Herein, we present a structure distortion strategy via Ni doping in MnO 2 to boost its Na+ storage performance. The as-obtained Ni-MnO 2 can deliver a high specific capacity of 379F g−1 at 1 A g−1, excellent rate performance of 281F g−1 at 20 A g−1, and a significantly enhanced cycling stability. In situ Raman results verify that Ni-MnO 2 with structure distortion can achieve a promising cycling life. Density functional theory results suggest that the structure distortion can efficiently modulate electron configuration by delocalizing electron. Furthermore, the Na+ diffusion energy barrier is remarkedly decreased in Ni-MnO 2 , thus accelerating ionic transport kinetics. An asymmetric supercapacitor based on Ni-MnO 2 cathode exhibits a high energy density of 114.6 Wh kg−1 at a power density of 3600 W kg−1. This work verifies the efficiency of structure distortion strategy on the improvement of Na ion storage performance in MnO 2 , which can be extended for the optimization of other electrode materials for energy storage. [ABSTRACT FROM AUTHOR]

The geometric, electronic structure and thermodynamic stability of Sc 2 O@C 92 has been characterized by using hybrid density functional theory calculations combined with statistical thermodynamic analyses. Results indicate that the isolated pentagon rule (IPR) isomers Sc 2 O@ C s (126339)-C 92 , Sc 2 O@ C 1 (126367)-C 92 and Sc 2 O@ C 1 (126390)-C 92 are favorable. Noteworthy, it is the first time to declare that fullerene isomer C s (126339)-C 92 could be considered as the suitable cage to encapsulate metallic cluster. The electronic properties of these three isomers were performed with frontier molecular orbital (HOMO and LUMO) analyses and bond order calculations. Finally, 13 C NMR and UV-vis-NIR spectra were simulated to provide valuable information for future experiments. [ABSTRACT FROM AUTHOR]