In situ growth of NixSy controlled by surface treatment of nickel foam as efficient electrocatalyst for oxygen evolution reaction
By Shang, Xiao; Li, Xiao; Hu, Wen-Hui; Dong, Bin; Liu, Yan-Ru; Han, Guan-Qun; Chai, Yong-Ming; Liu, Yun-Qi; Liu, Chen-Guang
Published in Applied Surface Science
2016
Abstract
Abstract In situ growth of NixSy with different crystal phases supported on different surface-treated (acidification or oxidation) nickel foam (NF) has been successfully achieved by a facile solvothermal process. {XRD} and {SEM} results show that crystal phase and morphology of NixSy have been greatly affected by the surface treatment of NF. {XRD} results show that the mixture crystal phases of NixSy have been obtained on both acid-treated {NF} (NF(a)) and oxidant treated {NF} (NF(o)). NixSy/NF(a) contains Ni3S2 and NiS, whereas NixSy/NF(o) has Ni3S2 and NiS2, implying different crystal phases derived from different surface treatment of NF. {SEM} images also reveal the different morphology of two samples based on pre-treatment support. NixSy/NF(a) displays unique conical agglomeration surrounded by porous structure. NixSy/NF(o) has the disorder stacking structure of nanosheets. Electrochemical measurements for oxygen evolution reaction (OER) show the enhanced performances of NixSy/NF(a) than NixSy/NF(o) and pure Ni3S2/NF as contrast samples, implying that NiS outperforms other types of NixSy. The mechanisms of sulfurization path of different surface-treated {NF} have been discussed. The facile surface treatment of {NF} may provide a new strategy to prepare excellent electrocatalysts for OER.