Koshtyal Yury, Mitrofanov Ilya, Nazarov Denis, Medvedev Oleg, Kim Artem, Ezhov Ilya, Rumyantsev Aleksander, Popovich Anatoly, Maximov Maxim Yu
Peter the Great Saint-Petersburg Polytechnic University, 195221 Saint Petersburg, Russia.
Saint Petersburg State University, 199034 Saint Petersburg, Russia.
Nanomaterials (Basel). 2021 Apr 2;11(4):907. doi: 10.3390/nano11040907.
Nanostructured metal oxides (MOs) demonstrate good electrochemical properties and are regarded as promising anode materials for high-performance lithium-ion batteries (LIBs). The capacity of nickel-cobalt oxides-based materials is among the highest for binary transition metals oxide (TMOs). In the present paper, we report the investigation of Ni-Co-O (NCO) thin films obtained by atomic layer deposition (ALD) using nickel and cobalt metallocenes in a combination with oxygen plasma. The formation of NCO films with different ratios of Ni and Co was provided by ALD cycles leading to the formation of nickel oxide (a) and cobalt oxide (b) in one supercycle (linear combination of a and b cycles). The film thickness was set by the number of supercycles. The synthesized films had a uniform chemical composition over the depth with an admixture of metallic nickel and carbon up to 4 at.%. All samples were characterized by a single NixCo1-xO phase with a cubic face-centered lattice and a uniform density. The surface of the NCO films was uniform, with rare inclusions of nanoparticles 15-30 nm in diameter. The growth rates of all films on steel were higher than those on silicon substrates, and this difference increased with increasing cobalt concentration in the films. In this paper, we propose a method for processing cyclic voltammetry curves for revealing the influence of individual components (nickel oxide, cobalt oxide and solid electrolyte interface-SEI) on the electrochemical capacity. The initial capacity of NCO films was augmented with an increase of nickel oxide content.
纳米结构金属氧化物（MOs）具有良好的电化学性能，被视为高性能锂离子电池（LIBs）有前景的负极材料。基于镍钴氧化物的材料在二元过渡金属氧化物（TMOs）中容量最高。在本文中，我们报告了通过原子层沉积（ALD）使用镍和钴茂并结合氧等离子体获得的Ni-Co-O（NCO）薄膜的研究。通过ALD循环实现了具有不同Ni和Co比例的NCO薄膜的形成，在一个超循环（a和b循环的线性组合）中导致氧化镍（a）和氧化钴（b）的形成。薄膜厚度由超循环次数设定。合成薄膜在深度方向上具有均匀的化学成分，含有高达4原子％的金属镍和碳杂质。所有样品均以具有立方面心晶格和均匀密度的单一NixCo1-xO相为特征。NCO薄膜的表面均匀，直径为15 - 30 nm的纳米颗粒夹杂物稀少。所有薄膜在钢上的生长速率高于在硅衬底上的生长速率，并且这种差异随着薄膜中钴浓度的增加而增大。在本文中，我们提出了一种处理循环伏安曲线的方法，以揭示各个组分（氧化镍、氧化钴和固体电解质界面 - SEI）对电化学容量的影响。NCO薄膜的初始容量随着氧化镍含量的增加而增大。
