Effects of phosphate precursors on morphology and oxygen evolution reaction activity of NiFe (oxy)hydroxide on nickel foams
(1. Hunan Key Laboratory of Nanophotonics and Devices, School of Physics and Electronics, Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
3. College of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha 410076, China;
4. NanoSYD, Mads Clausen Institute and DIAS Danish Institute for Advanced Study, University of Southern Denmark, Alsion 2, DK-6400 Sonderborg, Denmark;
5. Center of Advanced Lubrication and Seal Materials, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China)
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
3. College of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha 410076, China;
4. NanoSYD, Mads Clausen Institute and DIAS Danish Institute for Advanced Study, University of Southern Denmark, Alsion 2, DK-6400 Sonderborg, Denmark;
5. Center of Advanced Lubrication and Seal Materials, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China)
Abstract: NiFe (oxy)hydroxides nanosheets were synthesized on nickel foams via co-precipitation and electrochemical activation. It is found that the phosphate precursors (Na3PO4, Na2HPO4 and NaH2PO4) have diverse effects on the morphology and thus the oxygen evolution reaction activity of the formed final catalysts. The resulting NiFe (oxy)hydroxides nanosheets prepared with Na2HPO4 demonstrate a low overpotential of 205 mV to achieve a current density of 50 mA/cm2 with a Tafel slope down to 30 mV/dec in 1 mol/L KOH, and remain stable for 20 h during stability test.
Key words: NiFe (oxy)hydroxides; Fe-based phosphate; oxygen evolution reaction; electrochemical activation