Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath in the presence of fine MgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of m...Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath in the presence of fine MgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of methanol and ethanol in alkaline medium was investigated and compared with that of carbon coated pure Ni （Ni/C）. The chemical composition, phase structure, and surface morphology of the deposited nano‐composites were studied by energy dispersive X‐ray spectros‐copy, X‐ray diffractometry, and scanning electron microscopy, respectively. Different electrochemi‐cal techniques were used to estimate the catalytic activity of the prepared electrocatalyst anodes, including cyclic voltammetry （CV）, chronoamperometry, and electrochemical impedance spectros‐copy （EIS）. The Ni/C electrocatalyst alone exhibited remarkably low catalytic activity and poor stability toward the electrooxidation process. The inclusion of MgO significantly promoted the cata‐lytic activity of the Ni catalyst for the alcohol electrooxidation and enhanced its poisoning re‐sistance. The EIS results confirmed those of CV and revealed a lower charge transfer resistance and enhanced roughness for the Ni–MgO/C nano‐composite electrodes compared with those of Ni/C.展开更多
A commercial metal oxide sorbent for the desulphurization of coal-derived gas requires high desulphurization reactivity,mechanical strength,ability to regenerate,and stability to endure many sulfidationregeneration cy...A commercial metal oxide sorbent for the desulphurization of coal-derived gas requires high desulphurization reactivity,mechanical strength,ability to regenerate,and stability to endure many sulfidationregeneration cycles.In this paper,the sulfur capacity and multiple cycles of a nickel-modified ZnFe_(2)O_(4)sorbent prepared by the sol-gel auto-combustion method were measured in a fixed-bed reactor at middle temperature of 300℃(sulfidation temperature)and 500℃(regeneration temperature).Also,the BET surface area,pore volume,average pore diameter and X-ray diffraction(XRD)patterns of the sorbent through multicycles were studied.Multicycle runs indicate that the sulfidation reactivity decreases slightly during the second cycle and keeps steady in the following cycles.The results indicate that the nickel-modified ZnFe_(2)O_(4)keeps high reactivity and structural stability in the multicycle testing of sulfidation/regeneration.展开更多
文摘Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath in the presence of fine MgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of methanol and ethanol in alkaline medium was investigated and compared with that of carbon coated pure Ni （Ni/C）. The chemical composition, phase structure, and surface morphology of the deposited nano‐composites were studied by energy dispersive X‐ray spectros‐copy, X‐ray diffractometry, and scanning electron microscopy, respectively. Different electrochemi‐cal techniques were used to estimate the catalytic activity of the prepared electrocatalyst anodes, including cyclic voltammetry （CV）, chronoamperometry, and electrochemical impedance spectros‐copy （EIS）. The Ni/C electrocatalyst alone exhibited remarkably low catalytic activity and poor stability toward the electrooxidation process. The inclusion of MgO significantly promoted the cata‐lytic activity of the Ni catalyst for the alcohol electrooxidation and enhanced its poisoning re‐sistance. The EIS results confirmed those of CV and revealed a lower charge transfer resistance and enhanced roughness for the Ni–MgO/C nano‐composite electrodes compared with those of Ni/C.
基金supported by the State Key Development Program for Basic Research(973 Program)of China(Grant No.2005CB221203)the National Natural Science Foundation of China(Grant No.20706055).
文摘A commercial metal oxide sorbent for the desulphurization of coal-derived gas requires high desulphurization reactivity,mechanical strength,ability to regenerate,and stability to endure many sulfidationregeneration cycles.In this paper,the sulfur capacity and multiple cycles of a nickel-modified ZnFe_(2)O_(4)sorbent prepared by the sol-gel auto-combustion method were measured in a fixed-bed reactor at middle temperature of 300℃(sulfidation temperature)and 500℃(regeneration temperature).Also,the BET surface area,pore volume,average pore diameter and X-ray diffraction(XRD)patterns of the sorbent through multicycles were studied.Multicycle runs indicate that the sulfidation reactivity decreases slightly during the second cycle and keeps steady in the following cycles.The results indicate that the nickel-modified ZnFe_(2)O_(4)keeps high reactivity and structural stability in the multicycle testing of sulfidation/regeneration.
