Lone-Pair Interaction Excessive Elasticity and Mechanical Strength

3 Lone-Pair Interaction Excessive Elasticity and Mechanical Strength 

The hardness and the elastic modulus of P-C3N4 are expected to be comparable to or exceeding those of diamond [21,22]. Only a few were successful in preparing a-CsN4 and fS-C3N4 powders using the liquid-solid reaction between anhydrous 

In fact, the hardness of CN films decreases with increasing N content, instead. The excess electrons on N lower the hardness but enhance the elasticity [28]. The elasticity of the CN varies with substrate temperature and N content Increasing the substrate temperature from 100 to 350 °C at 2.5 mTorr N2 pressure, the elastic recovery increases from 60 to 90 % [14]. This value can be reduced to 68 % by increasing N2 pressure from 2.5 to 10 mTorr at a substrate temperature of 350 °C [29]. Although the highest hardness of CN available to date [20] ( 60 GPa) is below that of a diamond ( 100 GPa), the elasticity has been 

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