es7b00118_si_001.pdf (1.12 MB)
Converting Carbohydrates to Carbon-Based Photocatalysts for Environmental Treatment
journal contribution
posted on 2017-05-16, 00:00 authored by Zhuofeng Hu, Zhurui Shen, Jimmy C. YuCarbohydrates
in biomass can be converted to semiconductive hydrothermal carbonation
carbon (HTCC), a material that contains plenty of sp2-hybridization
structures. Under solar light illumination, HTCC generates photoexcited
electrons, holes, and hydroxyl radicals. These species can be used
for photocatalytic treatment such as water disinfection and degradation
of organic pollutants. The photocatalytic activity of HTCC can be
significantly enhanced by iodine doping. The enhancement mechanism
is investigated by density functional theoretical calculations and
electrochemical measurements. The iodine dopants twist and optimize
the structures of the sp2-hybridization in HTCC, thereby
favoring photon-induced excitation. Moreover, the iodine dopants facilitate
the charge transfer between different sp2-hybridization
structures, thus increasing the conductivity and activity of the HTCC.
An added benefit is that the I-doped HTCC exhibits lower cytotoxic
effect than the pure HTCC. In addition to monosaccharides (glucose),
disaccharides (sucrose), and polysaccharides (starch), we have also
transformed crops (e.g., rice), plants (e.g., grass), and even agricultural
waste (e.g., straw) and animal waste (e.g., cow dung). The conversion
of carbohydrates to HTCC may be considered as a “Trash to Treasure”
approach. We believe this discovery will attract a lot of attention
from researchers involved in environmental catalysis, waste recycling,
and pollution treatment.