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Atom transfer radical polymerization (ATRP) catalyzed by high oxidation state metal salts of FeX3 is developed for the first time in the absence of both external initiator and reducing agent. Methyl methacrylate (MMA) and styrene are polymerized successfully using FeX3 /Phosphorous ligands with well-controlled molecular weight distributions (=1.5). The molecular weight of the polymers increases with monomer consumption with the progress of time and the polymerization behaviors show a decent ATRP trend. Activators and initiators are suggested to generate in situ by the addition reaction of MMA and one equivalent of FeX3 . The PMMA synthesized from without-initiator system is characterized by (1) H, (13) C and DEPT (distortionless enhancement by polarization transfer nuclear magnetic resonance) nuclear magnetic resonance spectroscopy. Chain extension and copolymerization experiments prove the livingness of the obtained polymer.

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Herein, an extremely simple l-alanine-assisted pyrolysis method was proposed for the construction of a novel hierarchically porous hybrid of Fe4N–Fe supported on N-doped carbon nanobelts and Ketjen black carbon (denoted as Fe4N–Fe@N-C/N-KB). It has been found that the participation of l-alanine in pyrolysis can dramatically increase the total pyridinic-N/graphitic-N content in Fe4N–Fe@N-C/N-KB, which is peculiarly conducive to the enhancement of ORR performance. The in-site formation of the Fe4N–Fe heterojunction via the thermal reduction and decomposition of Fe3N as well as the introduction of cheap KB can significantly improve the ORR performance. As a result, the activity, durability, and methanol tolerance of this hybrid are comprehensively better than those of commercial 20 wt % Pt/C, promising future applications in practical devices. Density functional theory calculations disclose that the highly improved ORR activity of Fe4N–Fe@N-C/N-KB also benefits from the favorable electron penetration and excellent electronic conductivity between the Fe4N nanoparticles and the N-incorporated carbon frameworks.