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This paper focuses on the particle crushing mechanism of construction solid waste recycled aggregate (CWRA), particularly recycled concrete (RC) and recycled bricks (RB), using natural gravel (NG) as a control group. Compression tests, combined with the Weibull distribution, fractal dimension theory, and relative crushing rate, were conducted to investigate the crushing behavior of these materials under different loads. Results indicate that, under the same load, the crushing degree ranks from highest to lowest as RB, RC, and NG. The Weibull distribution effectively describes the crushing state, with "fragmentation" being the primary mode for most materials, while RC also exhibits "grinding." As the load increases, the relative crushing rate rises for all materials but slows beyond a certain load threshold, indicating greater difficulty in further crushing. The study identifies a load threshold of 400 kN, beyond which changes in void fraction and relative crushing rates become less significant, particularly in stronger aggregates. Highlights Identified that mortar attached to the RC surface is the primary cause of the increased particle crushing below 0.6 mm. Introduced Weibull distribution parameters a and b to accurately characterize the crushing state of RA particles. Revealed the errors between fractal dimension-based evaluations and the actual crushing state of RC particles. Proposed a two-stage crushing mode for RC. Determined the critical threshold value for the variation of crushing degree with load level. [ABSTRACT FROM AUTHOR]

This paper investigates the particle breakage mechanism of construction waste recycled aggregates [including recycled concrete (RC) as the strong component, recycled brick (RB) as the weak component, and natural gravel (NG) as the control strong component] under different load conditions. Through compression tests and mathematical model analysis based on the Weibull distribution, the study examines the changes in relative breakage rate (BE) and void fraction (Vc) of multicomponent recycled aggregates. The results reveal that under load, particle breakage occurs universally in recycled aggregates, especially in samples with higher RC content, which show a higher survival rate for larger particles and a reduction in smaller particle content. Additionally, the "survival of the fittest" effect, driven by differences in particle strength, becomes more pronounced as the strength difference increases. Incorporating NG into recycled aggregates can slow down the reduction in void fraction caused by particle breakage. Through the relationship model between load levels and brick-concrete ratios, the evolution of BE and Vc of recycled aggregates can be predicted, providing theoretical support for the design and application of permeable concrete. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIB) are increasingly recognized as a promising next‐generation energy storage technology, prized for their affordability and high safety profile. Yet, their widespread adoption is challenged by complex reaction mechanisms and the evolving nature of both the electrode material and interfaces, which remain critical barriers. This review underscores the utility of in situ and operando characterization techniques in AZIB systems, offering invaluable tools for tracking these intricate processes and deepening understanding of energy storage mechanisms. This review presents an extensive overview of cutting‐edge in situ and operando methods, emphasizing their crucial role in structural investigations of materials and interfaces during electrochemical processes. This review particularly focuses on the synergistic application of various in situ techniques, delving into the nuances of experimental setups and data interpretation. Finally, it addresses current challenges in the field and proposes potential strategies, aiming to enhance the impact and broaden the application of these techniques for future advancements and mechanistic insights in AZIB research. [ABSTRACT FROM AUTHOR]

The permeability performance made of recycled aggregate pervious concrete with macropores (M-RAPC) relates greatly to the macropore structure and seepage behaviors. However, the mechanism of the influence of pore structure on the permeability of M-RAPC is still unclear. Based on the high-resolution X-ray computer tomography (CT) and image processing technology, a three-dimensional (3D) pore structure model with macropore (>0.15 mm) was constructed, and the dimension of the representative elementary volume (REV) was determined to be 450×450×450 voxel3. Then, the quantitative characterization of the topological structure of macropore space and the simulation of pore flow were conducted. Finally, the relationship between macropore structure parameters and seepage behavior was discussed. The results showed that about 80% of macropores are in the range of 0.15–1 mm, and the pore coordination number is mostly concentrated within 20. The macropore distribution shows a great spatial heterogeneity, showing that the permeability anisotropy index is mainly larger than 1, and even up to 8. Besides, the permeability performance of M-RAPC is significantly correlated with macropore parameters (effective porosity, tortuosity, and fractal dimension). In summary, this study can better reveal the relationship between pore structure and seepage behaviors in M-RAPC and provide a reference for the skeleton structure and permeability performance optimization design of M-RAPC. [ABSTRACT FROM AUTHOR]

Successful conversion of CO2 into C2 products requires the development of new catalysts that overcome the difficulties in efficient light harvesting and CO–CO coupling. Herein, density functional theory (DFT) is used to assess the photoreduction properties of nitrogen-doped black phosphorus. The geometric structure, redox potential, first step of hydrogenation activation, CO desorption, and CO–CO coupling are systematically calculated, based on which the diatomic nitrogen-doped black phosphorus (N2@BPV) stands out. The calculated results of the CO2RR pathway demonstrate that N2@BPV has excellent selectivity and high activity for CH3CH2OH production. The results of the time-dependent ab initio nonadiabatic molecular dynamics simulation show that the diatomic N active sites of N2@BPV facilitate charge separation and inhibit electron–hole recombination. In addition, the activation mechanism of CO2 is studied. The main reason for CO2 activation is attributed to the imbalance in electron transfer that destroys the symmetry of CO2. We expect that our study will offer some theoretical guidance in CO2 conversion. [ABSTRACT FROM AUTHOR]

The rational construction of photocatalysts possesses tremendous potential to solve the energy crisis and environmental pollution; however, designing a catalyst for solar-driven overall water-splitting remains a great challenge. Herein, we propose a new MoS2-based photocatalyst (Co–P@MoS2), which skillfully uses the cobalt (Co) atom to stimulate in-plane S atoms and employs the phosphorus (P) atom to stabilize the basal plane by forming the Co–P bands. Using density functional theory (DFT), it was found that oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) can occur at the P site and S2 site of the Co–P@MoS2, respectively, and the dual-active sites successfully makes a delicate balance between the adsorption and dissociation of hydrogen. Furthermore, the improved overall water-splitting performance of Co–P@MoS2 was verified by analyzing the results of the electron structure and the dynamics of photogenerated carries. It was found that the imbalance of electron transfer caused by the introduction of the Co atom was the main contributor to the catalytic activity of Co–P@MoS2. Our study broadens the idea of developing photocatalysts for the overall water-splitting. [ABSTRACT FROM AUTHOR]

In electrochemical energy storage and conversion systems, urea oxidation reaction (UOR) can produce hydrogen and mitigate pollution from urea-rich wastewater in a low-energy manner, whereas the development of this technique was limited via a lack of economical and cost-effective UOR catalysts. Herein, a unique electrocatalyst of MoO3/Ni-N-C was synthesized from a Mo element-incorporated Ni-MOF by heating under an inert atmosphere. The prepared MoO3/Ni-N-C electrode shows superior activity toward UOR, which only needs a low potential of 1.42 V (vs RHE) at 50 mA cm–2 in 1.0 M KOH with 0.5 M urea. The excellent performance for UOR is attributed to the synergistic effect between molybdenum and nickel, the modulation of the electronic structure for the nickel site by MoO3, accelerating the charge transfer, and tuning the reaction interface adsorption energy to enhance electrocatalytic activity. This work provides strategies and directions for exploring other advanced UOR electrode material designs. [ABSTRACT FROM AUTHOR]

In this report, multiple-shell hollow silver and hematite composite microsphere has been prepared by using carbonaceous saccharide microsphere as template. The products were characterized by X-ray powder diffraction (XRD), scanning electronic microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDX). The core size and shell thickness of hollow spheres obtained can be manipulated by changing the concentration of metal salt. The unique multiple-shell hollow silver and hematite composite microspheres may be potentially used as gas-sensor materials for detecting various toxic gases.DOI: http://dx.doi.org/10.5564/mjc.v12i0.163 Mongolian Journal of Chemistry Vol.12 2011: 7-15

Lead (II) (Pb(II)) is widespread in water and very harmful to creatures, and the efficient removal of it is still challenging. Therefore, we prepared a novel sponge-like polymer-based absorbent (poly(amic acid), PAA sponge) with a highly porous structure using a straightforward polymer self-assembly strategy for the efficient removal of Pb(II). In this study, the effects of the pH, dosage, adsorption time and concentration of Pb(II) on the adsorption behavior of the PAA sponge are investigated, revealing a rapid adsorption process with a removal efficiency up to 89.0% in 2 min. Based on the adsorption thermodynamics, the adsorption capacity increases with the concentration of Pb(II), reaching a maximum adsorption capacity of 609.7 mg g−1 according to the Langmuir simulation fitting. Furthermore, the PAA sponge can be efficiently recycled and the removal efficiency of Pb(II) is still as high as 93% after five adsorption–desorption cycles. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses reveal that the efficient adsorption of Pb(II) by the PAA sponge is mainly due to the strong interaction between nitrogen-containing functional groups and Pb(II), and the coordination of oxygen atoms is also involved. Overall, we propose a polymer self-assembly strategy to easily prepare a PAA sponge for the efficient removal of Pb(II) from water. [ABSTRACT FROM AUTHOR]