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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]

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]

Facile and controllable synthesis of efficient and stable nonprecious electrocatalysts for the oxygen evolution reaction (OER) is crucial for prospective sustainable energy conversion and storage technologies. Iron-doped nickel sulfide nanosheet electrodes were synthesized through simple in situ sulfidation of nickel foil with ferrous chloride, which resulted in the formation of ultrathin Fe-doped Ni3S2 nanosheets on the Ni foam (NF) substrate (Fex-Ni3S2/NF). The developed Fe1-Ni2S3/NF electrocatalyst shows superb catalytic activity during the oxygen evolution reaction, owing to its high intrinsic activity, abundant active sites, and a superior transfer coefficient, requiring low overpotentials of only 244 and 306 mV at 100 mA cm–2 for the OER in 1.0 M KOH and 1.0 M KOH + 0.5 M NaCl solutions. This catalyst can maintain stable electrolysis in alkaline seawater for more than 100 h. The excellent activity and stability of this catalyst proved it to be an economical alternative to commercial noble metal-based catalysts in renewable energy-related technologies. [ABSTRACT FROM AUTHOR]

Anode materials have limited the development of sodium-ion batteries (SIBs). In this paper, the novel pomegranate-like mesoporous double carbon-coated Fe2P nanoparticles (Fe2P@C@NC), in which Fe2P is confined in the thin carbon shell derived from phytic acid and then wholly embedded into N-doped carbon network, can be applied as anode materials for SIBs. The elaborated structure presents several prominent merits, such as large specific surface area, pore-volume, excellent electronic conductivity network, and buffering volume expansion. All of these endow the structural integrity of Fe2P@C@NC material with excellent performance during charge–discharge cycles and guarantee speedy electrode reaction kinetics. As SIBs anode, Fe2P@C@NC material delivers an excellent reversible specific capacity of 408 mAh g−1 with almost no decay after the 100th cycles. And it also features excellent rate capability and splendid durability (attenuation rate of 0.05% per cycle with 1000th cycles) at high current density. These results confirm that the unique self-confined growth strategy has a great practical value in synthesizing advanced materials for next-generation energy storage systems. [ABSTRACT FROM AUTHOR]

Improving the electron–hole separation efficiency and accelerating the reaction kinetics of semiconductors are effective methods for improving the photoelectric catalytic activity of TiO2. In this study, sulfur-doped TiO2 (S–TiO2) nanorod arrays grown on a fluorine-doped SnO2 transparent conductive glass were successfully prepared using a microwave-assisted method for the photoelectrochemical (PEC) biosensing of glucose. The charge separation efficiency on S–TiO2 was evaluated by subjecting the prepared material to X-ray photoelectron spectroscopy, PEC measurements, and theoretical calculations based on density functional theory. The results clearly showed that the sulfur impurity state could not only reduce the bandgap but also serve as "stairs" to facilitate the electron transfer. Sulfur atoms that were successfully doped into TiO2 significantly promote the separation of the photogenerated carriers and improve the photocatalytic activity of the photoelectrode. Consequently, excellent glucose-detection sensitivities of 54 and 19 μA mM−1 cm−2 were achieved for fragments with sizes of 0.1–1.5 and 2–12 mM, respectively. [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 MoS 2 -based photocatalyst (Co-P@MoS 2 ), 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@MoS 2 , 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@MoS 2 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@MoS 2 . Our study broadens the idea of developing photocatalysts for the overall water-splitting.