jp7b06311_si_001.pdf (1.98 MB)
Probing Surface Functionality on Amorphous Carbons Using X‑ray Photoelectron Spectroscopy of Bound Metal Ions
journal contribution
posted on 2017-10-31, 00:00 authored by Andrew
J. Carrier, Inusa Abdullahi, Kelly A. Hawboldt, Barrie Fiolek, Stephanie L. MacQuarrieThe surface functionality
of amorphous carbons is difficult to
directly measure because of a lack of crystallinity and overwhelming
signals derived from the bulk material. Biochar, a form of amorphous
carbon containing considerable oxygen surface functionality, was probed
using metal ions and X-ray photoelectron spectroscopy to simultaneously
measure the presence and proximity of functional groups and determine
the preferred binding modes of a variety of metal ions. These binding
motifs were correlated to the efficiency of metal adsorption as determined
using the Langmuir isotherm and stability with respect to leaching.
Three binding motifs were apparent: physisorption (Cd2+, Mn2+, and Zn2+), chelation (Cu2+, Ni2+, and Zn2+), and hydrolysis/precipitation
(Cu2+, Ni2+, and Pb2+).