The formation of nanoporous Pd was studied by electro-chemical dealloying a rapidly-quenched Al70Pd17Fe13 quasicrystal alloy in dilute NaCl aqueous solution,and the electro-catalytic activity of the nanoporous Pd towa...The formation of nanoporous Pd was studied by electro-chemical dealloying a rapidly-quenched Al70Pd17Fe13 quasicrystal alloy in dilute NaCl aqueous solution,and the electro-catalytic activity of the nanoporous Pd towards methanol electro-oxidation was evaluated by cyclic voltammetry in 1 mol/L KOH solution.XRD and TEM analyses revealed that nano-decomposition of quasicrystal grains occurred in the initial stage of dealloying,and the fully dealloyed sample was composed of FCC-Pd phase.Scanning electron microscopy observation indicated that a maze-like nanoporous pattern was formed in the dealloyed sample,consisting of percolated pores of 5.20 nm in diameter in a skeleton of randomly-orientated Pd nano-ligaments with a uniform thickness of^5 nm.A retention of^12 at.%Al in the Pd nano-ligments was determined by energy dispersive X-ray spectroscopy(EDS).The nanoporous Pd demonstrated obvious electro-catalytic activity towards methanol electro-oxidation in alkaline environment.展开更多
A novel Fe-Pd bifunctional catalyst supported on mesh-type γ-Al<sub>2</sub>O<sub>3</sub>/Al was prepared and applied in the degradation of Rhodamine B (RhB). The monolithic mesh-type Fe-Pd/γ-...A novel Fe-Pd bifunctional catalyst supported on mesh-type γ-Al<sub>2</sub>O<sub>3</sub>/Al was prepared and applied in the degradation of Rhodamine B (RhB). The monolithic mesh-type Fe-Pd/γ-Al<sub>2</sub>O<sub>3</sub>/Al bifunctional catalyst could be separated from the solution directly and could synthesize H<sub>2</sub>O<sub>2</sub> in situ. The characterization results showed that Fe could improve the dispersion of Pd<sup>0</sup>, and the electronic interactions between Pd and Fe could increase the Pd<sup>0</sup> contents on the catalyst, which increased the productivity of H<sub>2</sub>O<sub>2</sub>. Furthermore, DFT calculations proved that the addition of Fe could inhibit the dissociation of O<sub>2</sub> and promote the nondissociative hydrogenation of O<sub>2</sub> on the surface of Fe-Pd/γ-Al<sub>2</sub>O<sub>3</sub>/Al, which resulted in the increasement of H<sub>2</sub>O<sub>2</sub> selectivity. Finally, the in-situ synthesized H<sub>2</sub>O<sub>2</sub> by Pd was furtherly decomposed in situ by Fe to generate<span lang="EN-US" style="white-space:normal;font-size:10pt;font-family:;" "=""><span lang="EN-US" style="white-space:normal;font-size:10pt;font-family:;" "=""><span style="white-space:normal;color:#FFFFFF;font-family:Roboto, " background-color:#d46399;"=""><img src="Edit_e6a13073-7151-40b7-b2c3-a59a59d064fc.png" alt="" />OH radicals to degrade organic pollutants. Therefore, Fe-Pd/ γ-Al<sub>2</sub>O<sub>3</sub>/Al catalysts exhibited excellent catalytic activity in the in-situ synthesis of H<sub>2</sub>O<sub>2</sub> and the degradation of RhB due to the synergistic effects between Pd and Fe on the catalyst. It provided a new idea for the design of bifunctional electro-Fenton catalysts. Ten cycles of experiments showed that the catalytic activity of Fe-Pd/γ-Al<sub>2</sub>O<sub>3</sub>/Al catalyst could be maintained for a long time.展开更多
基金Foundation item:Project(51671045)supported by the National Natural Science Foundation of ChinaProject(DUT18GF112)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(TZ2016004)supported by the Science Challenge Project,China
文摘The formation of nanoporous Pd was studied by electro-chemical dealloying a rapidly-quenched Al70Pd17Fe13 quasicrystal alloy in dilute NaCl aqueous solution,and the electro-catalytic activity of the nanoporous Pd towards methanol electro-oxidation was evaluated by cyclic voltammetry in 1 mol/L KOH solution.XRD and TEM analyses revealed that nano-decomposition of quasicrystal grains occurred in the initial stage of dealloying,and the fully dealloyed sample was composed of FCC-Pd phase.Scanning electron microscopy observation indicated that a maze-like nanoporous pattern was formed in the dealloyed sample,consisting of percolated pores of 5.20 nm in diameter in a skeleton of randomly-orientated Pd nano-ligaments with a uniform thickness of^5 nm.A retention of^12 at.%Al in the Pd nano-ligments was determined by energy dispersive X-ray spectroscopy(EDS).The nanoporous Pd demonstrated obvious electro-catalytic activity towards methanol electro-oxidation in alkaline environment.
文摘A novel Fe-Pd bifunctional catalyst supported on mesh-type γ-Al<sub>2</sub>O<sub>3</sub>/Al was prepared and applied in the degradation of Rhodamine B (RhB). The monolithic mesh-type Fe-Pd/γ-Al<sub>2</sub>O<sub>3</sub>/Al bifunctional catalyst could be separated from the solution directly and could synthesize H<sub>2</sub>O<sub>2</sub> in situ. The characterization results showed that Fe could improve the dispersion of Pd<sup>0</sup>, and the electronic interactions between Pd and Fe could increase the Pd<sup>0</sup> contents on the catalyst, which increased the productivity of H<sub>2</sub>O<sub>2</sub>. Furthermore, DFT calculations proved that the addition of Fe could inhibit the dissociation of O<sub>2</sub> and promote the nondissociative hydrogenation of O<sub>2</sub> on the surface of Fe-Pd/γ-Al<sub>2</sub>O<sub>3</sub>/Al, which resulted in the increasement of H<sub>2</sub>O<sub>2</sub> selectivity. Finally, the in-situ synthesized H<sub>2</sub>O<sub>2</sub> by Pd was furtherly decomposed in situ by Fe to generate<span lang="EN-US" style="white-space:normal;font-size:10pt;font-family:;" "=""><span lang="EN-US" style="white-space:normal;font-size:10pt;font-family:;" "=""><span style="white-space:normal;color:#FFFFFF;font-family:Roboto, " background-color:#d46399;"=""><img src="Edit_e6a13073-7151-40b7-b2c3-a59a59d064fc.png" alt="" />OH radicals to degrade organic pollutants. Therefore, Fe-Pd/ γ-Al<sub>2</sub>O<sub>3</sub>/Al catalysts exhibited excellent catalytic activity in the in-situ synthesis of H<sub>2</sub>O<sub>2</sub> and the degradation of RhB due to the synergistic effects between Pd and Fe on the catalyst. It provided a new idea for the design of bifunctional electro-Fenton catalysts. Ten cycles of experiments showed that the catalytic activity of Fe-Pd/γ-Al<sub>2</sub>O<sub>3</sub>/Al catalyst could be maintained for a long time.
