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Electrocatalytic CO2‐to‐syngas (gaseous mixture of CO and H2) is a promising way to curb excessive CO2 emission and the greenhouse gas effect. Herein, we present a bimetallic AuZn@ZnO (AuZn/ZnO) catalyst with high efficiency and durability for the electrocatalytic reduction of CO2 and H2O, which enables a high Faradaic efficiency of 66.4 % for CO and 26.5 % for H2 and 3 h stability of CO2‐to‐syngas at −0.9 V vs. the reversible hydrogen electrode (RHE). The CO/H2 ratios show a wide range from 0.25 to 2.50 over a narrow potential window (−0.7 V to −1.1 V vs. RHE). In situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy combined with density functional theory calculations reveals that the bimetallic synergistic effect between Au and Zn sites lowers the activation energy barrier of CO2 molecules and facilitates electronic transfer, further highlighting the potential to control CO/H2 ratios for efficient syngas production using the coexisting Au sites and Zn sites. [ABSTRACT FROM AUTHOR]

Single atom alloys (SAAs) often bring new chemistry in heterogeneous catalysis and well-defined structure for the study of structure–activity relationship (SAR). However, the existing pressure gap causes the reported SARs quite divergent. Herein, we have studied CO activation over Ni/Cu(100) SAAs in ultrahigh vacuum (UHV) and millibar range. While the Ni SAAs formed on Cu(100) significantly enhance the CO adsorption strength under UHV conditions, the CO treatment at elevated pressure leads to notable surface carbon and oxygen deposition through surface reaction. Density functional theory calculations revealed that either dissociation or disproportionation is thermodynamically forbidden for the coverage of CO less than 5/16 ML. However, these two reaction pathways can be opened at higher CO coverages due to the elevated energy state involving repulsion between adsorbed CO. This work uncovers the initial activation process of CO and demonstrates one typical cause for the pressure gap in surface science study as well. [ABSTRACT FROM AUTHOR]

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 introduced Cr 3 C 2 phase into FeNi alloys suppress the thermal coarsening of alloy nanoparticles and induce the charge rearrangement around interface, thereby increasing the number of active sites and intrinsic activity of per sites, respectively. [Display omitted] Exploring high active electrocatalysts for oxygen evolution reaction (OER) is of great significance for a sustainable hydrogen economy. The development of non-precious transition metals, with sufficient active sites and ample intrinsic activity, remains a challenge. Herein, a new type of FeNi–Cr 3 C 2 heterostructure anchored on carbon sheets (FeNi–Cr 3 C 2 @C) was reported, which can effectively catalyze OER with swift kinetics and outstanding intrinsic activity. The introduced Cr 3 C 2 phase not only serves as a support material but also effectively suppresses the thermal coarsening of FeNi alloy nanoparticle. The FeNi–Cr 3 C 2 @C displays a robust OER activity with a low overpotential of 283 mV at the current density of 10 mA cm−2, a high turnover frequency value of 1.69 s−1 at the overpotential of 300 mV (10 times higher than that of FeNi@C) and good stability in alkaline media. Density functional theory calculations (DFT) calculations show that Cr 3 C 2 can facilitate the generation of electron-rich region at the Ni site in FeNi alloys as an active site, exhibiting an optimized adsorption behavior toward oxygen intermediate species with regard to decreased thermodynamic energy barriers. Our work opens up a promising path to modulate the electrocatalytic active sites using inexpensive and durable Cr 3 C 2 for electrochemical catalytic reactions. [ABSTRACT FROM AUTHOR]