Gaixiu Yang

Iron single‐atom catalysts (Fe SACs) offer excellent performance for the oxygen reduction reaction (ORR). However, their catalytic activity remains limited by the coordination structure and the accessibility of the active sites. Optimizing the local coordination and pore structure of the catalyst is imperative. Herein, we report a dual‐template strategy using oxygen‐rich lignin to synthesize Fe single‐atom catalysts with asymmetric Fe‐N ₃ O coordination embedded in hierarchical porous carbon (HPC). Lignin serves both as the carbon precursor and a coordination modulator, while Zn/MgO dual templates facilitate the creation of a tri‐modal (micro/meso/macro) pore architecture. Operando spectroscopy and DFT calculations reveal that the asymmetric Fe‐N ₃ O configuration downshifts the d‐band center of Fe, which weakens *OOH adsorption and accelerates charge transfer, leading to enhanced intrinsic activity. The optimized Fe‐N ₃ O@HPC catalyst exhibits exceptional ORR activity in 0.1 M KOH, with a half‐wave potential of 0.87 V vs. RHE, surpassing Pt/C by 40 mV. Moreover, it exhibits significantly smaller decay over 30 h than commercial Pt/C. In zinc‐air batteries, the catalyst delivers a peak power density of 174.2 mW cm ⁻² and a specific capacity of 807 mAh g _Zn ⁻¹ . This research offers a cost‐effective methodology to design and fabricate high‐performance catalysts for ORR.

Entropy increment driven short crystallite formation transcends classical thermodynamics.

A competitive adsorption strategy for anti-leaching CaO/La₂O₃ catalyst construction for biodiesel production.

The plateau capacity of a hard carbon anode plays a crucial role in achieving the high energy density of sodium-ion batteries. However, the loss of plateau capacity due to polarization at high current densities imposes significant limitations on hard carbon applications. Ultra-micropores could maintain plateau capacity at high current densities but are generally prepared accompanied by micropores and mesopores that deteriorate the Na-ion storage performance. Herein, a hard carbon with ultra-micropores is prepared by a protonation-mediated strategy using an N, P co-doped biomass precursor. The P dopants favor reducing the interaction between N and C so that the confined volatiles of NH₃ could be utilized to create ultra-micropores concentrated at 0.4–0.8 nm. These ultra-micropores enable the hard carbon to deliver a reversible capacity of 386 mA h g⁻¹ at 20 mA g⁻¹, a high plateau capacity of 173 mA h g⁻¹, and an excellent rate capability of 106 mA h g⁻¹ at 2 A g⁻¹. The plateau capacity and rate capability are superior to those of the reported hard carbons. This work provides a new approach for ultra-micropore construction within hard carbons and a new perspective for sodium-ion batteries toward high energy and power densities.

The global accumulation of waste plastics has led to severe environmental pollution, posing a serious threat to ecosystems. Conventional disposal methods, such as landfilling, mechanical recycling, and incineration, remain limited by low conversion efficiency, modest economic benefits, and the risk of secondary pollution. Converting plastics into high-value functional carbon materials offers a promising strategy for waste plastic recovery. This review systematically summarizes the physicochemical properties of major plastics, including polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, and polystyrene. It then discusses representative functional carbon materials—such as carbon nanotubes, graphene, porous carbon, carbon spheres, carbon nanosheets, carbon quantum dots, and soft carbon—derived from waste plastics using both conventional processes (direct pyrolysis, catalytic pyrolysis, one-pot synthesis, and templating methods), and emerging technologies (flash Joule heating and microwave-assisted pyrolysis). Furthermore, the applications of these functional carbon materials in environmental remediation (e.g., CO₂ adsorption, antibiotic removal, electromagnetic wave absorption, and heavy metal ion adsorption), and energy storage (e.g., lithium-ion batteries and supercapacitors) are reviewed. This work provides a timely overview of recent advances in the field and highlights pathways toward the sustainable utilization of waste plastics.