TY - JOUR
T1 - Single sheet iron oxide
T2 - An efficient heterogeneous electro-Fenton catalyst at neutral pH
AU - Huang, Li-Zhi
AU - Zhu, Mingtao
AU - Liu, Zizheng
AU - Wang, Zongping
AU - Hansen, Hans Christian B.
PY - 2019/2/15
Y1 - 2019/2/15
N2 - In order to overcome the inefficiency of heterogeneous electro-Fenton process for water treatment at neutral pH, single sheet iron oxide (SSI) derived from layered Fe(II)-Fe(III) double hydroxides (green rusts) was fabricated on an indium tin oxide electrode via layer by layer assembly and used in an undivided electrolysis cell. Use of radical scavengers demonstrated the formation of oxygen radicals by electrochemical reduction of oxygen at the SSI electrode, and the key role of hydroxyl radicals ([rad]OH) and superoxide anion (O2
–) radicals in degradation of the azo dye orange II. Analysis of degradation products by UV–vis, LC–MS and GC–MS further demonstrated that direct reduction toke place in addition to indirect oxidation. The reactivity of SSI as a heterogeneous electro-Fenton catalyst is two order of magnitude higher than its homogenous counterparts. The SSI electrode was highly stable as the dye degradation did not decrease after use for 19 h with no Fe leaching. The high dye removal efficiency was maintained in a wide pH range from 7 to 10 and in different supporting electrolytes, demonstrating the application of this process under various conditions mimicking natural waters.
AB - In order to overcome the inefficiency of heterogeneous electro-Fenton process for water treatment at neutral pH, single sheet iron oxide (SSI) derived from layered Fe(II)-Fe(III) double hydroxides (green rusts) was fabricated on an indium tin oxide electrode via layer by layer assembly and used in an undivided electrolysis cell. Use of radical scavengers demonstrated the formation of oxygen radicals by electrochemical reduction of oxygen at the SSI electrode, and the key role of hydroxyl radicals ([rad]OH) and superoxide anion (O2
–) radicals in degradation of the azo dye orange II. Analysis of degradation products by UV–vis, LC–MS and GC–MS further demonstrated that direct reduction toke place in addition to indirect oxidation. The reactivity of SSI as a heterogeneous electro-Fenton catalyst is two order of magnitude higher than its homogenous counterparts. The SSI electrode was highly stable as the dye degradation did not decrease after use for 19 h with no Fe leaching. The high dye removal efficiency was maintained in a wide pH range from 7 to 10 and in different supporting electrolytes, demonstrating the application of this process under various conditions mimicking natural waters.
KW - Advanced oxidation processes
KW - Electro-Fenton
KW - Green rust
KW - Heterogeneous electro catalyst
KW - Single sheet iron oxide
UR - http://www.scopus.com/inward/record.url?scp=85054787036&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2018.10.026
DO - 10.1016/j.jhazmat.2018.10.026
M3 - Journal article
C2 - 30336334
AN - SCOPUS:85054787036
SN - 0304-3894
VL - 364
SP - 39
EP - 47
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
ER -