SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3608-8
Polymeric carbon nitride (PCN) is a promising photocatalyst for H2O2 production due to its visible-light response, low cost, and high selectivity for the two-electron oxygen reduction reaction (ORR). However, its H2O2 yield is limited by narrow light absorption, low charge separation efficiency, and insufficient active sites. Here, crystalline poly(heptazine imide) (PHI)-based carbon nitride with highly dispersed In sites and N defects was prepared via an ionothermal method using LiCl/KCl molten salts. The large π-conjugated system and N defects enhance visible-light harvesting. Remaining K+ ions in nitrogen cavities act as interlayer electron channels, while N defects induce asymmetric charge distribution on the heptazine network, promoting interlayer and in-plane charge separation and transfer. In sites accelerate charge transfer dynamics and serve as active sites for ORR. The synergistic effect of metal modification and defect engineering boosts electron delocalization, significantly improving photocatalytic activity. The H2O2 production rate of 10InPHI reaches 15.3 mmol g−1 h−1 via a two-step single-electron ORR pathway, underscoring the potential of modified carbon nitride for efficient H2O2 photosynthesis.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202604004
Tire wear particles (TWPs) are emerging pollutants and constitute the dominant type of microplastics (MPs) in urban stormwater runoff, accounting for up to 90% of MPs in some cases. They are characterized by small size, high mobility, complex composition, and significant toxicity. Current research on TWPs remains fragmented, lacking a comprehensive understanding of their environmental behaviors and pollution control in aquatic systems. This review systematically analyzes the enrichment and vectoring roles of TWPs for coexisting pollutants, and their environmental fate, including ecotoxicological impacts, detection methodologies, release of intrinsic additives, and aggregation and sedimentation behaviors. Drawing on insights from other microplastic studies, the paper explores control technologies across the pollution pathway—source, transport, and terminal treatment—and proposes feasible management strategies. Key findings indicate that TWPs can adsorb heavy metals and organic contaminants, with adsorption capacities influenced by aging processes. Their aggregation is governed by solution chemistry, with critical coagulation concentrations varying with ionic strength and pH. The release of additives such as zinc and benzothiazoles is significant, posing ecological risks. Future research should focus on real-water aggregation mechanisms, additive release under natural conditions, long-term performance of treatment facilities like constructed wetlands under TWPs stress, enzymatic degradation pathways, and integration of AI, big data, and IoT for cost-effective detection and risk modeling. This review provides a scientific basis for developing targeted pollution control measures for TWPs in aquatic environments.