Systematic investigation of close-packed silica nanospheres monolayer under sintering conditions

In this paper, we have quantified and investigated the effect of various sintering temperature on close-packed Silica Nanospheres (SNs) monolayers. SNs with diameters of 140, 175 and 220 nm were fabricated by an effective and reliable spin-coating technique. The fabricated SNs monolayers were sintered up to 1200 °C and were analyzed from FESEM to investigate in details for local and extended transformations in their structural and morphological properties. A distinct “neck-formation” was observed and was quantified with different particle size distribution as well as surface packing density. It was observed that SNs monolayer undergoes intra-particle reformation in the form of shrinkage in individual SNs and compactification of growth domains, followed by inter-particle sintering. A geometrical model was developed to determine the curvature radius and interpenetration depth thus enabling us to quantify the parameters that dominate the dynamics of the sintering process for such non-porous SNs.