ABSTRACT
ABSTRACT: Carbon fibers (CFs) decorated by Co2P nanoparticles and carbon nanotubes were prepared via needle-less electrospinning technique. Formation of catalytically active Co2P nanoparticles and growth of carbon nanotubes were monitored in open and closed sintering environment at different sintering exposure times. Higher porosity, important in the catalytic reaction for easier penetration of electrolyte into the CFs, was achieved by mixing two immiscible polymers with natrium dodecyl sulfate and subsequent heat treatment process. Structure and morphology of the prepared modified carbon fibers were characterized by XRD, SEM and TEM. The time of heat exposure at the sintering temperature of 1200 °C and closure of the sintering space showed distinct effect on the growth and shape of carbon nanotubes. SEM and Raman spectroscopy revealed that closure of the system led to the formation of carbon nanotubes with smaller diameters and less structural disorder. Comparing of as-prepared CFs revealed that CFs with Co2P sintered in the closed system exhibited the best electrocatalytic activity for hydrogen evolution reaction due to lower overpotential and smaller Tafel slope in acidic solution.
ABSTRACT
The endoglucanase gene (endC) of Fibrobacter succinogenes BL2 encodes a protein of 620 amino acids (EGC) that shows similarity with family E1 cellulases, and particularly with EGB from F. succinogenes S85. Alignment of the amino acid sequence of family E1 cellulases revealed that EGC is composed of a N-terminal domain and a large catalytic domain of 453 residues containing an extension of 60 residues at its C-terminal part which is not present in other family E1 enzymes. EGC shows the same substrate specificity as EGB, and is also inhibited by EDTA. However, its optimal pH (7.0) and temperature (37 degrees C) for activity are different.
