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Electrochemical CO2 reduction (CO2RR) over molecular catalysts is a paramount approach for CO2 conversion to CO. Herein, we report a novel phthalocyanine-derived catalyst synthesized by a two-step method with a much improved electroconductivity. Furthermore, the catalyst contains both Ni–N4 sites and highly dispersed metallic Ni nanoclusters, leading to an increased CO2RR currents by two folds. Isotope labelling study and in situ spectroscopic analysis demonstrate that the existence of metallic Ni nanoclusters is the key factor for the activity enhancement and can shift the CO2RR mechanism from being electron transfer (ET)-limited (forming ∗COO−) to concerted proton-electron transfer (CPET)-limited (forming CO).

Electrochemical reduction of CO2 is promising to utilize the intermittent renewable electricity and transform CO2 into value-added products, simultaneously. Herein, we designed a cobalt phthalocyanine-based catalyst supported on pyridine-functionalized carbon nanotubes (CoPc-py-CNT). This novel hybrid catalyst exhibited a high activity (TOFCO: 34.5 s−1 at −0.63 V vs. RHE) and selectivity (FECO > 98%) for electrochemical CO2 reduction. To the best of our knowledge, it is the best one among all reported molecular based electrocatalysts for CO2-to-CO conversion. Furthermore, structure characterizations (such as Raman and X-rays photoelectron spectroscopy), loading-dependent electrochemical analysis and mechanistic studies revealed that pyridine groups, through axial coordination with Co, not only functioned as physical promoters to improve the dispersion of cobalt phthalocyanine but also tuned the electronic structure of Co sites to increase the intrinsic turnover frequency.

The relationship between consciousness and feature binding has long been a topic of debate. Although they may be associated, there is growing evidence supporting the notion that feature binding and visual consciousness can be separated to some degree. In our study, we manipulated the visibility of priming stimuli, which consisted of color-motion features, and then measured the effects of those manipulations on reporting of cued targets' direction of rotation. A priming effect was observed even when the priming stimuli were invisible, implying that the color-motion features of the prime could bind unconsciously. These findings support the notion that, at least under certain conditions, feature binding and visual consciousness are separable psychological processes wherein feature binding is not sufficient to establish visual awareness.

Electrodeposited Bi, Sn and In catalysts are employed as model catalysts to investigate the nature of active sites and the influence of surface hydroxyls on the formation of formate during CO2 electroreduction (CO2RR). With SEM, XPS, in situ XRD, electrochemical measurements and DFT calculations, the active sites are Bi0, SnO and In2O3, with their affinities to hydroxyls following the trend of Bi0

Herein, we report a facile direct solid-state reaction strategy using black phosphorus coupled black titania to prepare uniform BP-BT materials with enhanced wide-spectrum sunlight absorption properties. BP-BT possesses a typical crystalline core-amorphous shell (TiO2@TiO2−x) structure with numerous oxygen vacancies and electron-rich P dosage in the layer and exhibits excellent solar-to-chemical conversion for efficient photocatalytic CO2 reduction to CH4. Notably, the optimized BP-BT shows superior activity of CH4 formation of 16.8 μmol g−1 h−1, a selectivity of 80.1 %, and excellent stability for CO2 transformation under solar light irradiation. The kinetic isotope effects and in situ diffuse reflectance infrared Fourier transform spectroscopy analysis reveal that the adsorption and chemical activation of inert CO2 molecule over the surface-defective and surface basic-site-modulated BP-BT are kinetically-relevant steps. The existence of crucial intermediate of CO2− species from single-electron CO2 reduction route and the rate-determining step of C O bond cleavage in photocatalytic CH4 generation were also confirmed.

Urban rail systems are developing rapidly, and due to the limited space of the metro tunnel, once a fire occurs will result in disastrous consequences. Full-scale fire experiment is an effective testing method for fire prevention of metro systems. Aiming at the characteristics of a long continuous downhill distance and large lifting height in the sloped metro tunnel, a full-scale fire experiment under vehicle operations was carried out on a metro line. By changing the operated speed and direction of the vehicle, the airflow velocity, ceiling temperature distribution, and smoke layer characteristics in the tunnel were studied. The results show that when a fire occurs in a sloped tunnel, the running vehicle will produce piston effect, and the airflow will be affected by the stack effect and the piston effect simultaneously, which will change the flow field in this area, and then affect the flame shape, ceiling temperature and smoke distribution. Through the dimensionless treatment of the ceiling temperature, a longitudinal attenuation distribution model of the ceiling temperature was established, which reveals the law of fire smoke migration and diffusion under different vehicle operating conditions. The conclusions of this study could technically support the smoke control design in such metro tunnel fire scenarios.

The influence of basic oxide promoters on copper-chromium-iron oxide catalysts was investigated to determine the nature of surface oxygen species and structure-activity relationship for the reverse water-gas shift reaction. The catalysts were characterized with in situ XRD, in situ Raman, in situ XPS, in situ HS-LEIS and H2-TPR. Two surface oxygen sites with different reduction characteristics were found to be present. The overall CO2 activation rate was found to correlate with both the number and reducibility of the more active oxygen species that were likely associated with the Cu-FeOx interfacial regions for enhanced hydrogen spillover. While addition of K2O somewhat preserved the interfacial regions and facilitated the reduction kinetics of surface oxygen, both Na2O and CaO significantly suppressed the availability of metallic Cu as well as the Cu-FeOx interfaces, leading to decreased reactivity. These findings provide a direction to promote the copper-iron catalysts by creating more metal-metal oxide interfacial sites.

Bringing forward the concentration of practical teaching system reform ideas are based on product-oriented, hierarchical progressive. The idea associates all parts of practice, establishing a large framework system. This approach reflects the intrinsic link between knowledge, reached through the practice of teaching will be the focus of a comprehensive knowledge of the purpose. Its implementation will help to change the traditional teaching mode, and to further promote the theory of teaching, thereby raising the overall quality of training.