Fe_xCo_3−xO₄ Nanohybrids Anchored on a Carbon Matrix for High‐Performance Oxygen Electrocatalysis in Alkaline Media

Abstract

Herein, we report a systematic study of nanohybrids (NHs) of various FeÀ Co oxides anchored on to carbon matrix for highperforming oxygen electrode reactions. Fe 2.1 Co 0.9 O 4 /C NH having minor content of Co 3 + exhibited superior oxygen reduction reaction (ORR) performance than the other compositions and benchmark Pt/C. It exhibits a current density of 8.4 mA cm À 2 in 0.1 M KOH for ORR compared to the benchmark Pt/C (3.81 mA cm À 2 ). It also reveals superior stability and durability than Pt/C. It can retain 92 % of its initial current up to 7000 s. Also, the Fe 2.1 Co 0.9 O 4 /C NH delivers the best Tafel slope of 72.6 mV dec À 1 . Additionally, the Co 3 + rich Fe 0.9 Co 2.1 O 4 /C NH demonstrated superior oxygen evolution reaction (OER) performance than the Pt/C, RuO 2 and other compositions in 0.1 M KOH solution. Thus, the obtained electrocatalysts (ECs) having bimetallic active site demonstrates unique electrocatalytic properties and the carbon matrix can increase stability and thus provide additional catalytic active sites. This makes them a significant candidate for oxygen electrocatalysis.

BiVO4 Photoanodes Modified with Synergetic Effects between Heterojunction Functionalized FeCoOx and Plasma Au Nanoparticles

“…Moreover, it can also be calculated that the atomic ratio of Fe and Co in the selected area is Fe:Co = 2.2:1. In the relevant publications on the preparation of Au and FeCoO x , the content of Au, Fe, and Co is generally below 5% [30], and the most significant improvement in the PEC performance of FeCoO x at present belongs to the work of Wang et al, where the relative atomic ratio of Fe:Co is Fe:Co = 1.1:1 [14].…”

“…Moreover, it can also be calculated that the atomic ratio of Fe and Co in the selected area is Fe:Co = 2.2:1. In the relevant publications on the preparation of Au and FeCoOx, the content of Au, Fe, and Co is generally below 5% [30], and the most significant improvement in the PEC performance of FeCoOx at present belongs to the work of Wang et al, where the relative atomic ratio of Fe:Co is Fe:Co = 1.1:1 [14]. Figure 3 displays the high-resolution X-ray photoelectron spectroscopy (XPS) elemental spectrum of the BiVO4/Au/FeCoOx photoanode, which contains information on the composition and chemical states of elements in the composite photoanode.…”