Haiwei Guo

Photoexcited nitroarenes serve as HAT catalysts in continuous flow for aliphatic C–H functionalization, enabling Giese additions to electron-deficient alkenes and divergent radical-trapping transformations.

The massive CO ₂ emission arising from fossil fuel combustion has exacerbated climate crises and disrupted ecological balance, driving the need for sustainable processes for the efficient utilization of renewable resources. Lignocellulose represents as a promising alternative to fossil‐based feedstock, while the inherent structural recalcitrance significantly hinders its efficient conversion. Mechanical ball milling is considered as a potential strategy for lignocellulose valorization for its intensive mechanical energy to disrupt the physical architecture of lignocellulose. Currently, the existing reviews mostly focus on the application of mechanical ball milling for biomass‐based materials preparation, lacking integrated discussions on the application for lignocellulose separation and depolymerization. This review emphasized the synergistic effect of the mechanochemical strategy for structural disruption and chemical activation, which includes the effective separation of lignin and cellulose and their depolymerization to obtain value‐added monomers and platform chemicals. Furthermore, the potential and energy advantages of mechanical ball milling for industrial‐scale applications were elaborated by comparing different mechanochemical strategies, combined with energy consumption comparison and process scaling. Finally, future perspectives on the precise optimization of mechanical ball‐milling systems are proposed. This review offers promising guidance on the valorization of lignocellulosic biomass.

Industrial waste lignin can be used as a sustainable resource to prepare carbon materials, which has been considered an important strategy for the substitution of coal-based carbon. However, a review summarizing the design mechanism of heteroatom-doped lignin-derived carbon materials and their application performance is lacking. Herein, we reviewed the recent progress on heteroatom-doped lignin-based carbon applied in energy storage applications such as batteries and capacitors, environmental fields such as removing contaminants from the air and water, substance testing for iron/chromium ions, and catalysis. More importantly, we present a critical discussion with respect to the effect of heteroatom-doping (e.g., N-doping and N/S/O/P co-doping) on the physicochemical properties including the BET area, defect structure, hydrophilicity/hydrophobicity, electric conductivity, and electron density of lignin-based carbon materials. Particularly, the effects of the above-mentioned properties on the reversible capacity, rate performance, and cycling performance of batteries; the capacitance and energy density of capacitors; and the adsorption capacity of lignin-based carbonaceous adsorbents for the removal of pollutants are concluded. Finally, we propose the future perspective and challenges in applying lignin-based carbon materials in energy storage and environmental fields.

Iron oxides are commonly used catalysts for the removal of polychlorinated aromatic hydrocarbons from incinerators. Here, we provide a proof of concept that facet engineering can be exploited to simultaneously improve the catalytic activity, water resistance and stability of iron oxides. Using 1,2-dichlorobenzene oxidation as a surrogate reaction, we show that α-Fe₂O₃ nanorods with predominantly exposed {110} facets (NR-{110}) exhibit lower T_50% and T_90% (temperatures of 50% and 90% removal) and higher CO₂ selectivity under a dry condition than α-Fe₂O₃ nanoparticles with {012} facets, α-Fe₂O₃ nanosheets with {001} facets, and commercial α-Fe₂O₃. NR-{110} also exhibits superior water resistance (without exhibiting the “V-shaped” curve in 1,2-dichlorobenzene removal originated from the competitive adsorption of water) and much better stability. Spectroscopic evidence based on pyridine-adsorbed Fourier transform infrared and X-ray photoelectron spectroscopy, chemisorption analysis based on O₂ temperature-programmed desorption, H₂ temperature-programmed reduction and H₂O temperature-programmed desorption and theoretical calculations demonstrate that the higher abundance of Lewis and Brønsted acid sites, higher concentration of surface active oxygen, more negative adsorption energy and lower C–Cl bond broken energy barrier associated with the (110) facet collectively enable fast reaction kinetics and more complete contaminant destruction. Additionally, the facet-specific interaction mode of water gives greater water resistance, and the abundant Brønsted acid sites on the (110) facet effectively provide H⁺ to prevent the accumulation of chloride ions, thus enhancing stability.