Defect chemistry, increasing charge, and spin density in the carbon lattice are keys to the advancement of any alternative non-precious cathodic oxygen reduction electrocatalyst for broad dissemination of polymer electrolyte fuel cells (PEFCs). In view of this prospective, we developed porous carbon from a biomass-derived source, such as corncob (CC) waste, and heteroatom N and F doping on it to increase functionalities and defects. Fe was further incorporated in N–F/CC-C to enhance the oxygen reduction reaction (ORR) activity and power density in PEFCs. Finely mesoporous carbon derived from CC undergoes structural transformation, having numerous open edge active sites after N–F co-doping, and alters the textural characteristics favorable for ORR. The Fe/N–F/CC-C catalyst shows outstanding ORR activity, insensitivity toward CH3OH in alkaline conditions, and insignificant deprivation in ORR activity after a recurrent 10 000 potential cycles that prevails a highly enticing ORR electrocatalyst for PEFCs. The presence of active pyridinic, pyrrolic, and graphitic kinds of nitrogen along with ionic and semi-ionic active bonds between C and F in graphitic arrangement of the Fe/N–F/CC-C catalyst cumulatively ameliorates the catalytic activity. Furthermore, generation of maximal C–C bond polarization, redistribution in charge density, and high spin densities in the carbon lattice of the catalysts were theoretically investigated, which cumulatively boost the ORR activity.

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In an attempt to develop nonprecious metal electrocatalyst, herein, we report borylation of graphitic carbon nanofiber (GNF) and codoping of Co, Ni toward a oxygen reduction reaction (ORR) catalyst and their application in anion exchange membrane fuel cells (AEMFCs). Boron (B) doping in a carbon matrix creates a C–B bond with lower bond energy to facilitate insertion of metal atoms in the carbon matrix beneficial for ORR activity. Ni and Co doping individually and in combination with the B/GNF increases positive charge clouds surrounding metal centers and facilitates O2 adsorption and catalytic activity. The DFT studies on the catalysts are extensively carried out to measure the band gaps, atomic compositions of frontier molecular orbitals, and charge clouds distribution on the catalysts and correlated with the electrochemical findings. Further, Ni and Co doping creates positive charge cloud, facilitating O2 adsorption through lowering the band gap. Synergistic effect of Ni and Co in the catalyst (Ni20Co20@B/GNF-H) toward ORR activity is clearly established and later demonstrated in an anion exchange membrane fuel cells (AEMFCs) as a potential cathode catalyst. Ni20Co20@B/GNF-H showed an eminent ORR activity, competent CH3OH tolerance in alkaline medium without much decrease in ORR activity even after 10,000 potential cycles. Assessing the fuel cell performance evaluation in AEMFC, Ni20Co20@B/GNF-H catalyst, delivers a peak power density of ∼70 mW cm–2 at a load current density of ∼138 mA cm–2 under ambient pressure and temperature. This nonprecious boron-functionalized GNF-H catalyst opens an era toward the development of a low cost, highly efficient metal based cathodic ORR electrocatalyst for AEMFC applications.

The adsorption of farmorubicine, methotrexate and 5-fluorouracil on adsorbents based on polyethylene grafted with polyacrylic acid (polyacrylate content Δp of 4, 15 and 80%) and polyacrylamide (polyacrylamide content Δp of 14%) has been investigated. A comparative estimation of the sorptive activity of the investigated adsorbents with respect to different antitumour compounds has been carried out. The influence of NaCl addition on the parameters of the kinetics and equilibrium adsorption of farmorubicine and methotrexate has been established.