Synthesis of Cu₉S₈/carbon nanotube nanocomposites with high electrocatalytic activity for the oxygen reduction reaction

Abstract

We have synthesized Cu 9 S 8 /carbon nanotube (CNT) nanocomposites (NCs) with high electrocatalytic activity for direct methanol fuel cells (DMFCs). Cu 9 S 8 /CNT NCs are prepared from Cu(NO 3 ) 2 , CNTs, and thioacetamide in the presence of poly(vinylpyrrolidone) under alkaline conditions. There are Cu 9 S 8 nanoparticles (diameter: 50 AE 6 nm) and aggregates on the surfaces of CNTs. The as-prepared Cu 9 S 8 / CNT NC modified electrodes provide a four-electron pathway for the oxygen reduction reaction (ORR) in alkaline media. Three representative Cu 9 S 8 /CNT electrodes (mass loading: 1.63 mg cm À2 ) provide a mean limiting current density of 3.43 AE 0.03 mA cm À2 (each with three measurements) at a constant scan rate of 1 mV s À1 and a rotation rate of 3600 rpm. At a constant potential of À0.5 V, the kinetic rate constant for the Cu 9 S 8 /CNT is 2.82 Â 10 À2 cm s À1 , revealing higher activity of the Cu 9 S 8 /CNT electrodes in the ORR. The Cu 9 S 8 /CNT relative to Pt/C electrodes is more tolerant against methanol and carbon monoxide poisoning. These low-cost, stable, and highly active Cu 9 S 8 /CNT electrodes have great potential for use in DMFCs.

Palladium copper nanosponges for electrocatalytic reduction of oxygen and glucose detection

“…30 In addition, our approach relative to reported ones allowed preparation of large-scale PdCu NSs at lower temperature for a shorter period of Fig. The PdCu NS catalysts synthesized at 25 mM SDS provided greater oxygen reduction 10 stability (43,200 s) than commercial CNT and Pt/C electrodes; their currents decreased by 68.7 and 61.5 %, respectively, after 15000 s. 51 The results show advantages of good stability, excellent electrocatalytic activities, and cost effectiveness of the PdCu NSs, which hold great potential for use in DMFCs. 39 The PdCu NSs catalysts synthesized at 25 mM SDS provided greater glucose oxidation stability (at least 90 sweeping for 43,200 s) and higher EASA value than the others, showing its great potential to be used as anodes in DGFCs.…”

“…In other words, the PdCu NSs had a higher accessible surface area. 51 The high mass activity for ORR provided by the PdCu NS-modified electrode was mainly due to a high EASA value, efficient direct cathodic reduction, and 5 a synergistic effect provided by the bimetallic PdCu NSs. 15,42,47 The asprepared PdCu NSs have such a high electrocatalytic activity, mainly due to large EASA and synergistic effect.…”

Significantly enhanced oxygen reduction activity of Cu/CuN x C y co-decorated ketjenblack catalyst for Al–air batteries

“…Cho et al [20] developed nano-CuS@Cu-BTC (BTC = 1,3,5-benzenetricarboxylate) composite using Cu-BTC and thioacetamide as raw materials, which exhibited an onset potential of 0.91 V (vs. RHE, reversible hydrogen electrode) and quasi-four-electron transfer pathway ( n = 3.82). Periasamy et al [21] prepared Cu 9 S 8 /CNTs nanocomposites with an onset potential of −0.18 V (vs. SCE, saturated calomel electrode) and a near four-electron pathway in alkaline media for ORR. Wu et al [19] prepared Cu-N@C catalyst utilizing copper phthalocyanine (CuPc) and dicyandiamide, and found that the highly exposed Cu(I)-N active sites greatly promoted the ORR catalytic activity.…”

Facile Synthesis of Polyhedral Pd Nanocrystals as a Highly Active and Methanol-Tolerant Electrocatalyst for Oxygen Reduction

“…As shown in Figure B , the electron transfer numbers of polyhedral Pd/XC‐72 (3.52∼3.64) are apparently larger than the compared Pd/XC‐72 (without Fe 3+ , 3.03) and Pd/XC‐72 (without CTAB, 2.47‐2.51), but slightly lower than the commercial Pd/C (3.82‐3.94). The result indicates that polyhedral Pd/XC‐72 catalyst undergoes a four‐electron‐transfer pathway dominated for ORR ,…”