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Abstract Converting CO₂into industrially useful products is an appealing strategy for utilization of an abundant chemical resource. Electrochemical CO₂reduction (eCO₂R) offers a pathway to convert CO₂into CO and ethylene, using renewable electricity. These products can be efficiently copolymerized by organometallic catalysts to generate polyketones. However, the conditions for these reactions are very different, presenting the challenge of coupling microenvironments typically encountered for the transformation of CO₂into highly complex but desirable multicarbon products. Herein, we present a system to produce polyketone plastics entirely derived from CO₂and water, where both the CO and C₂H₄intermediates are produced by eCO₂R. In this system, a combination of Cu and Ag gas diffusion electrodes is used to generate a gas mixture with nearly equal concentrations of CO and C₂H₄, and a recirculatory CO₂reduction loop is used to reach concentrations of above 11% each, leading to a current‐to‐polymer efficiency of up to 51% and CO₂utilization of 14%. 

Abstract Electrochemically controlled redox-switchable polymerization uses an electric potential to bias the monomer selectivity of a catalyst. Many ferrocene-appended catalysts can exist in two oxidation states, a neutral reduced state and an oxidized cationic state. Electrochemical generation of the oxidized cationic state produces a charged species whose counteranion is determined by the identity of the supporting electrolyte anion. Herein, the role the counteranion has on monomer selectivity and polymerization kinetics is investigated. Minimal differences in monomer selectivity in the reduced state was found, however, in the oxidized state, the coordinating ability of the counteranion greatly influenced the rate of polymerization. How activity differences governed by the choice of electrolyte can be utilized to access desired diblock copolymers is also described. 

Achieving ultranarrow absorption linewidths in the condensed phase enables optical state preparation of specific non-thermal states, a prerequisite for quantum-enabled technologies. 

A facile synthetic strategy to prepare a new type of on-chain polyperoxide bearing intermolecular peroxy bonds is reported. Polyketone from the copolymerization of ethylene and carbon monoxide was quantitatively transformed into amorphous and powdery polyperoxide using aqueous hydrogen peroxide at room temperature. This synthetic pathway allowed the highly selective and complete conversion of carbonyl groups into intermolecular peroxy groups that can initiate free radical graft copolymerization without generating fragmentary alkoxyl radical species. The thermal properties of polyperoxide were characterized by differential scanning calorimetry and thermogravimetric analysis, and the polyperoxide was further ap-plied as a macroinitiator to prepare densely grafted copolymers, polyethylene-g-poly(4-methyl styrene) and polyethylene-g-poly(methyl methacrylate), via grafting from approach. 

A nickel bromide complex supported by a non-innocent ferrocene-chelating heteroscorpionate ligand, [(fc(PPh₂)(BH(3,5-Me₂pz)₂)NiBr)] ((fc^P,B)NiBr, fc = 1,1′-ferrocenediyl, pz = pyrazole), was synthesized and characterized.