Fig. 4.

Catalytic selectivity to azoxy products of various Co₁/G SACs catalysts. a Schematic illustration of the hydrogenation of nitroarenes using different catalysts. Histograms of the selectivity to azoxy products for the hydrogenation of 1-chloride-3-nitrobenzene (b), 1-chloride-4-nitrobenzene (c), and 1-methyl-4-nitrobenzene (d) at ~100% conversion of nitroarenes by using different Co₁/G SACs including Co₁/G-0.4, Co₁/G-0.8, Co₁/G-1.3, Co₁/G-2.0, Co₁/G-2.5, Co-NPs/G, and Pt/carbon. e Turnover frequency (TOF) of the different catalysts tested in the selective hydrogenation of nitrobenzene