Bhatti Adeel Liaquat, Aftab Umair, Tahira Aneela, Abro Muhammad Ishaq, Kashif Samoon Muhammad, Aghem Muhammad Hassan, Bhatti Muhamad Ali, HussainIbupoto Zafar
Institute of Physics, University of Sindh Jamshoro 76080 Sindh Pakistan.
Mehran University of Engineering and Technology 7680 Jamshoro Sindh Pakistan.
RSC Adv. 2020 Mar 31;10(22):12962-12969. doi: 10.1039/d0ra00441c. eCollection 2020 Mar 30.
Designing a facile and low-cost methodology to fabricate earth-abundant catalysts is very much needed for a wide range of applications. Herein, a simple and straightforward approach was developed to tune the electronic properties of cobalt oxide nanostructures by doping them with nickel and then using them to catalyze the oxygen evolution reaction (OER) in an aqueous solution of 1.0 M KOH. The addition of a nickel impurity improved the conductivity of the cobalt oxide, and further increased its activity towards the OER. Analytical techniques such as scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and powder X-ray diffraction (XRD) were used to investigate, respectively, the morphology, composition and crystalline structure of the materials used. The nickel-doped cobalt oxide material showed randomly oriented nanowires and a high density of nanoparticles, exhibited the cubic phase, and contained cobalt, nickel and oxygen as its main elements. The nickel-doped cobalt oxide also yielded a Tafel slope of 82 mV dec and required an overpotential of 300 mV to reach a current density of 10 mA cm. As an OER catalyst, it was shown to be durable for 40 h. Electrochemical impedance spectroscopy (EIS) analysis showed a low charge-transfer resistance of 177.5 ohms for the nickel-doped cobalt oxide, which provided a further example of its excellent OER performance. These results taken together indicated that nickel doping of cobalt oxide can be accomplished a facile approach and that the product of this doping can be used for energy and environmental applications.
设计一种简便且低成本的方法来制备储量丰富的催化剂，对于广泛的应用来说是非常必要的。在此，我们开发了一种简单直接的方法，通过用镍对氧化钴纳米结构进行掺杂来调节其电子性质，然后将其用于催化1.0 M KOH水溶液中的析氧反应（OER）。镍杂质的加入提高了氧化钴的导电性，并进一步增强了其对OER的活性。使用扫描电子显微镜（SEM）、能量色散光谱（EDS）和粉末X射线衍射（XRD）等分析技术分别研究了所用材料的形态、组成和晶体结构。镍掺杂的氧化钴材料呈现出随机取向的纳米线和高密度的纳米颗粒，呈现立方相，并且以钴、镍和氧作为主要元素。镍掺杂的氧化钴还产生了82 mV dec的塔菲尔斜率，并且需要300 mV的过电位才能达到10 mA cm的电流密度。作为一种OER催化剂，它被证明在40小时内具有耐久性。电化学阻抗谱（EIS）分析表明，镍掺杂的氧化钴具有177.5欧姆的低电荷转移电阻，这进一步证明了其优异的OER性能。综合这些结果表明，通过一种简便的方法可以实现对氧化钴的镍掺杂，并且这种掺杂产物可用于能源和环境应用。
