Iron and nickel doped CoSe2 as efficient non precious metal catalysts for oxygen reduction

Abstract

Iron and nickel doped CoSe2 as efficient non precious metal catalysts for oxygen reduction AbstractIron and nickel doped CoSe2 were prepared by solvothermal method, and they were proved to be ternary chalcogenides by series of physical characterization. The effects of the iron and nickel contents on the oxygen reduction reaction were investigated by electrochemical measurements, and the highest activities were obtained on Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2, respectively. Both Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2 presented four-electron pathway. Furthermore, Co0.7Fe0.3Se2 exhibited more positive cathodic peak potential (0.564 V) and onset potential (0.759 V) than these of Co0.7Ni0.3Se2 (0.558 V and 0.741 V). And Co0.7Fe0.3Se2 displayed even superior stability and better tolerance to methanol, ethanol and ethylene glycol crossover effects than the commercial Pt/C (20 wt% Pt). Abstract: Iron and nickel doped CoSe2 were prepared by solvothermal method, and they were proved to be ternary chalcogenides by series of physical characterization.The effects of the iron and nickel contents on the oxygen reduction reaction were investigated by electrochemical measurements, and the highest activities were obtained on Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2, respectively. Both Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2 presented four-electron pathway. Furthermore, Co0.7Fe0.3Se2 exhibited more positive cathodic peak potential (0.564 V) and onset potential (0.759 V) than these of Co0.7Ni0.3Se2 (0.558V and 0.741V). And Co0.7Fe0.3Se2 displayed even superior stability and better tolerance to methanol, ethanol and ethylene glycol crossover effects than the commercial Pt/C (20 wt% Pt).

Synthesis of Cobalt‐Iron Chalcogenide Clusters as Precursors for Catalysts of Oxygen Electroreduction in Alkali Media

“…The observed ORR onset potential is almost the same as that of 0.759 V reported by Yu for Co 0.7 Fe 0.3 Se 2 in acid solution . It is 50–100 mV lower than ca.…”

“…150–170 mV more negative than those at Pt(20 %)/C (Figure S2). A similar difference was observed by Yu et al when studying iron‐modified cobalt selenide in an acidic solution …”

“…5 mA cm –2 for the CoFe 2 Se 2 /C sample and ca. 6.5 mA cm –2 for the CoFe 2 Te 2 /C sample observed at 0.4 V and 1600 rpm, are higher than those reported for the same conditions by Feng and Wu (4.2 and 3.5 mA cm –2 for CoSe 2 /C and Co 1.67 Te 2 /C, correspondingly), and those at Co 0.7 Fe 0.3 Se 2 in 0.5 m H 2 SO 4 . This indicates that in the range of working potentials of the fuel cell cathode the iron‐modified cobalt chalcogenide catalysts are more efficient than unmodified ones, providing higher current densities in both acidic and alkaline medium.…”

“…Recently Yu et al have demonstrated that iron‐modified cobalt selenide catalyst prepared via solvothermolysis is more efficient in the reaction of oxygen electroreduction in acid medium than unmodified cobalt chalcogenide . In present work iron‐containing cobalt chalcogenide clusters [C 5 HMe 4 CoSe 2 Fe 2 (CO) 7 ] and [C 5 HMe 4 CoTe 2 Fe 2 (CO) 7 ] are synthesized and used as precursors for the preparation of catalysts supported on a carbon black Vulcan XC‐72.…”

Microwave Synthesis of Carbon‐Supported Cobalt Nickel Selenide Ternary Catalyst Toward the Oxygen Reduction Reaction

“…Employing similar synthesis methods, the mesoporous Ni 0.89 Co 0.11 Se 2 nanosheets on Ni foam exhibited high activity and excellent stability for hydrogen evolution reaction (HER) in a wide pH range, while the dandelion‐like Ni 0.33 Co 0.67 Se microspheres delivered the power conversion efficiency of 9.01 % when used as a counter electrode for dye‐sensitized solar cells under AM 1.5G irradiation . The introduction of Fe or Ni into CoSe 2 by hydrothermal process was also found to improve the ORR activities and stabilities of unsupported (Co,Fe) Se 2 through affecting the electronic structure of the transition metal and specific surface area . The larger onset potential of unsupported Co 0.7 Fe 0.3 Se 2 (0.759 V) was obtained as compared with those of unsupported Co 0.7 Ni 0.3 Se 2 (0.741 V) and CoSe 2 (0.708 V) in O 2 saturated 0.5 mol L −1 H 2 SO 4 solutions.…”