Nitrogen-doped carbon dot/activated carbon nanotube-supported copper nanoparticles as an efficient electrocatalyst for the oxygen reduction reaction

Critical role of dissolved oxygen and iron–copper synergy in dual-metal/char catalyst systems

“…For Cu-BC, the CV curve presented a reduction peak with the highest current density, and the LSV curve also exhibited the highest current density and onset potential ( E onset ), indicating the highest oxygen reduction activity. 9,39 To sum up, the above findings proved that Fe/Cu-BC had the capability of activating DO largely from the contribution of Cu species. Meanwhile, Fe species promoted the synergistic catalysis.…”

Cobalt–Copper-Embedded Nitrogen-Doped Carbon Nanostructures Derived from Zeolite Imidazolate Frameworks as Electrocatalysts for the Oxygen Reduction Reaction

“…The HO 2 − yields (%) were calculated using the following equation: 200 × (I r /N)/ ((I d + I r )/N), where I d and I r represent the ring and the disk in the RRDE (Figure 8b,c) and N indicates collection efficiency. 55 The order of the HO 2 − yields was as follows: CoCu@NC-750 (9.9%) < CoCu@NC-1000 (10.7%) < CoCu@NC-500 (22.1%), which indicates that the HO 2 − yields increased as the n value decreased. This is consistent with the RDE results, indicating that the ORR of the proposed CoCu@NC-750 nanostructure likely follows a direct fourelectron transfer pathway.…”

“…Subsequently, the RRDE technique was used to calculate the yield of the peroxide (HO 2 – ) intermediates and the n values of the different catalysts. The HO 2 – yields (%) were calculated using the following equation: 200 × ( I r / N )/(( I d + I r )/ N ), where I d and I r represent the ring and the disk in the RRDE (Figure b,c) and N indicates collection efficiency . The order of the HO 2 – yields was as follows: CoCu@NC-750 (9.9%) < CoCu@NC-1000 (10.7%) < CoCu@NC-500 (22.1%), which indicates that the HO 2 – yields increased as the n value decreased.…”

Hollow Nickel Nanochains Coated with Nickel-Iron Hydroxide for Oxygen Evolution

“…As the number of measurements increases, the ring electrode exhibits a slight decrease in current, consistent with the reduction in current density observed during the stability experiments. The collection efficiency of each catalyst transitioning from the OER to the ORR was estimated using eq % ( O 2 ) = 100 × ( I r / N ) / false( ( I d ) where I d is the average current of the disk electrode over 50 s during the OER at E appl = +1.5 V (vs RHE), I r is the average current of the ring electrode at E appl = +0.45 V (vs RHE), and N is the ring correction coefficient for each catalyst determined by the reduction of Fe(CN) 6 4–/3– redox couple.…”

“…The collection efficiency of each catalyst transitioning from the OER to the ORR was estimated using eq 6. 52 I N I %(O ) 100 ( / )/((…”