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Adding impurities or doping through adsorption is an effective way to tailor the properties of graphene-based materials. The capability of making predictions with regard to the trends of elemental adsorption on graphene is crucial to a better understanding of the more complex adsorption cases. It also provides useful guidelines for fabricating 2D graphene materials with novel properties. In this review, we show trends of elemental adsorption on graphene with elements of the periodic table, based on previous studies and supplemented with our recent calculations. We also discuss the effects of atomic ratios on some properties of this element-adsorbed graphene system. Trends of properties studied include binding energy, most stable site, adatom height, migration energy, Fermi energy shift, graphene distortion, magnetization, charge transfer, and electronic energy band gap at Fermi energy. Certainly, there is ample scope to investigate the electronic structures of elemental adsorption on graphene based on period and group of the periodic table, and atomic ratio. Key words: graphene, DFT, adatom, adsorption, band gap. L'ajout d'impuretes ou le dopage via l'adsorption est une facon efficace pour ajuster les proprietes des materiaux bases sur le graphene. Notre capacite a faire des predictions regardant les tendances de l'adsorption d'elements sur du graphene est tres importante dans le but de mieux comprendre les cas d'adsorption plus complexes. Elle s'avere egalement utile comme guide pour fabriquer des materiaux 2D a base de graphene et ayant des proprietes nouvelles. Dans cette revue, nous montrons les tendances d'adsorption des elements du tableau periodique, en se basant sur des etudes anterieures supplementees de nos calculs recents. Nous analysons aussi les effets des rapports atomiques sur certaines proprietes de ce systeme de graphene a adsorption d'elements. Les proprietes etudiees incluent l'energie de liaison, le site le plus stable, la hauteur d'adatomes, l'energie de migration, le deplacement de l'energie de Fermi, la distorsion du graphene, la magnetisation, le transfert de charge et la bande electronique interdite a l'energie de Fermi. De toute evidence, il y a amplement de choses a etudier sur la structure electronique suivant l'adsorption d'elements sur du graphene, selon la periode et le groupe du tableau periodique et le rapport atomique. [Traduit par la Redaction] Mots-cles: graphene, DFT, adatome ou atome adsorbe, adsorption, bande interdite. PACS Nos.: 73.20.At, 73.20.Hb, 73.22.Pr., 1. Introduction Graphene is a two-dimensional hexagonal lattice made of carbon atoms with nearest distance between the carbon atoms = 1.42 Å (1Å = [10.sup.-10] m). It became a 'marvel' [...]

Ternary cobalt-based metal oxide (ZnCo2O4) has been successfully coated onto aluminum substrate via sol–gel method. The coatings were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and UV–Vis–NIR spectrophotometry. Thermal degradation of the coatings was probed by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Model of crystal growth kinetics and density functional theory (DFT) calculations further probed the crystalline structure evolution. The predicted ZnCo2O4 crystalline structures were confirmed by XRD and EDX. The grain growth kinetic model for ZnCo2O4, derived from Lifshitz–Slyozov–Wagner (LSW) theory, determined that the growth of crystalline phases is unaffected by the annealing temperature; however, the crystallites' sizes decreased with the increase in precursor concentration. DFT analysis indicated that structural energy stability between the bulk state and slabs of ZnCo2O4 was at two oxygen layers (O-layers) with an optimum grain width of 17.21 Å. Interestingly, the morphology of ZnCo2O4 represented a rose-like template structure formed by inter-connecting layers of nanosheets. This unique surface morphology enhanced the optical absorptance properties up to α = 70.7%. Highlights: The kinetics, structural and absorptance properties of zinc and cobalt mixed oxides are not well understood due to lack of prior consolidated research findings. Therefore, our research focuses on the formation, grain growth kinetics, mineralogical and surface structure, as well as the absorptance properties of zinc and cobalt mixed oxides coating on aluminum substrates. This represents a novel holistic analysis within the ambit of sol-gel science. Furthermore, the novelty involves the incorporation of the experimental results complemented by grain growth kinetics modelling using LSW model and simulation of the grain size against the coating thickness of ZnCo2O4. We also developed a model at a smaller scale and utilized the density functional theory (DFT) to calculate the stability of each case in the model. [ABSTRACT FROM AUTHOR]