Developing Pt-free electrocatalysts is the main solution for reducing the intolerable cost of hydrogen production through the hydrogen evolution reaction (HER), while sustaining rare-earth elements. Thus, we have synthesized carbon nanoflakes derived from carbon cloth doped with controllable boron atoms (Bx/C), where x refers to boron atomic contents (x = 3.42, 5.04, 9.79, and 14.64 wt.%), driven by the impregnation of carbon cloth containing polyester (CC) in an aqueous solution of boric acid, followed by drying at 80 °C for 1 h and then calcination at 500 °C for 2 h under nitrogen. The method allows the conversion of one-dimensional CC to a two-dimensional flake-like structure, in situ enriched with B-C motifs as active sites for HER. The HER performance depends on interfacial interaction of boron with carbon, but B₁/C (B = 3.42 wt %) was the optimum with a HER current of 370 mA/cm² at −0.78 V, overpotential at 10 mA/cm² (ƞ_HER@10) of 372 mV, Tafel slope of 166 mV/dec, and stability for 60 h, besides a hydrogen production rate of 1.57 mol·g⁻¹·h⁻¹ of catalyst, due to endowing surface area, intermolecular charge transfer, and electrical conductivity. The data obtained may pave the way for designing heteroatom-integrated carbon from biomass for promoting low-cost HER.

The aim of this work is to study the radical copolymerization of acrylonitrile with 1-chloro-3-piperidin-2-propylacrylate and to study the structure and properties of the synthesized copolymers. Ammonium persulfate was used as the radical initiator. Water and dimethylformamide were used as solvents. Under these conditions the process proceeds heterogeneously in water, and homogeneously with high speed in dimethylformamide. The synthesis rate of the 1-chloro-3-piperidino-2-propylacrylate and acrylonitrile copolymers increases with increasing temperature in the studied solvents. Experimental studies have shown that copolymerization does not proceed in the absence of the initiator and this indicates a radical nature of the reaction. The structure of synthesized compounds was confirmed by IR spectral analyses. The participation of multiple bonds of both monomers during copolymerization was determined. The composition of copolymers has been determined which indicates that the copolymer formed at early stages is enriched with 1-chloro-3-piperidino-2- propylacrylate units. The values of the monomers relative activities were calculated by Feinemann-Ross method. The found values of copolymerization constants are r1=0.28, r2=0.62 and the constant value of the copolymerization product is less than unity proving both types of formed polymer radicals react much faster with foreign monomer than with their own.

In the paper the results of synthesis of binary copolymers with different contents of monomer units by radical copolymerization of 1-chloro-3-piperidino-2-propylacrylate with acrylonitrile in organic solvent medium at 30-60°C in the presence of radical initiator using free-radical polymerization technique not up to high degrees of transformation by gravimetric method are given. Dinitrilazobisobisobutyric acid was used as the radical initiator. Water and dimethylformamide were used as solvent. Under these conditions in water the process proceeds heterogeneously, and in dimethylformamide homogeneously and with high speed. The synthesis rate of copolymers of 1-chloro-3-piperidino-2-propylacrylate with acrylonitrile in the studied solvents increases with increasing temperature. Experimental studies have shown that copolymerization does not proceed in the absence of the initiator and this indicates a radical nature of the reaction. The structure of synthesized compounds was confirmed by IR, NMR spectral analyses. The participation of multiple bonds of both monomers during copolymerization was determined. The composition of copolymers has been determined which indicates that the copolymer formed at early stages is enriched with 1-chloro-3-piperidino-2- propylacrylate units. The values of relative activities of monomers were calculated by Feinemann-Ross method. The found values of copolymerization constants 7:1=0.28, 7:2=0.62 and the value of product of copolymerization constants less than unity that both types of formed polymer radicals react much faster with foreign monomer than with their own.