1 research outputs found
Effect of Product Removal in Hydrogen Peroxide Electrosynthesis on Mesoporous Chromium(III) Oxide
On-site electrosynthesis of hydrogen peroxide (H2O2) is a promising alternative technology to the
conversional
centralized anthraquinone oxidation process. Here, we report a platinum
group metal (PGM)-free H2O2 electrogenerator
with mesoporous Cr2O3 and NiCo2O4 used as electrocatalysts for oxygen reduction and evolution
reactions (ORR and OER), respectively. The catalysts were synthesized
via a hydrothermal synthesis route and had pore sizes of 3 and 7 nm
and specific surface areas of 112 and 62 m2 gā1, respectively. Mesoporous Cr2O3 was evaluated
in a half cell with 0.1 M KOH for electrocatalytic oxygen reduction,
which shows 2.2 transferred electrons per oxygen and an in situ H2O2 yield of 70%. This enables the electrosynthesis
of hydrogen peroxide in alkaline medium using Cr2O3 as a 2e-ORR-H2O2 electrocatalyst,
with oxygen evolution as an auxiliary reaction on NiCo2O4. The effect of electrolyte flow on the H2O2 electrogenerator was investigated. It is observed that
one-way feeding of the catholyte suppresses deterioration of the electrocatalyst
and allows a faradic conversion up to ā¼90% with a production
rate of ā¼0.36 [g (hĀ·gcat)ā1], operating within the cell voltage of 1.2 V. This work demonstrates
both a viable method for electrosynthesis of H2O2 production using PGM-free electrocatalysts and the possibility to
obtain a high faradic efficiency by mitigating the effect from catalyst
degradation