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The concept behind nanocatalysis may be understood by considering the impact of the intrinsic properties of nanomaterials (Figure 3.1) that have a vital impact on their catalytic activity and may be categorized as:

1 (i) Quantities that are directly related to bond length, such as the mean lattice constant, atomic density, and binding energy. Lattice contraction in a nano-solid induces densification and surface relaxation.

2 (ii) Quantities that depend on the cohesive energy per discrete atom, such as self-organization growth; thermal stability; coulomb blockade; critical temperature for phase transitions, evaporation in a nano-solid; and the activation energy for atomic dislocation, diffusion, and chemical reactions.

3 (iii) Properties that vary with the binding energy density in the relaxed continuum region such as the Hamiltonian that determine the entire band structure and related properties such as band gap, core level energy, photo-absorption, and photoemission.

4 (iv) Properties from the joint effect of the binding energy density and atomic cohesive energy such as the mechanical strength Young’s modulus, surface energy, surface stress, extensibility and compressibility of a nano-solid, as well as the magnetic performance of a ferromagnetic nano-solid.

Figure 3.1 Diagram of effect of intrinsic property on nanocatalyst. (Source: https://www.slideshare.net/foolishcrack/nanocatalyst-108342252) [55].

By precisely controlling the size, shape, spatial distribution, surface composition and electronic structure, and thermal and chemical stability of the individual nano components, they can be widely used in catalysis with newer properties and activity.