XRD Studies on Metamorphic Changes of the Dissimilarly Graphitized Carbonaceous Materials

Abstract

One of the unique yet functional properties of the carbonaceous materials is an irregular change in their internal heterogeneity and graphene layouts upon graphitizing themselves. The precise investigations of such type phase transitions inclusive of reshuffling/restructuring of the sporadically arranged graphene C–atoms, and thereby acquiring crystallite growths & contractions, crystallinity, graphitization degree, extent of structural orders, dissimilar range pores & porosity networks, etc., are indispensable for understanding the actual transformation aptitudes of the low temperature amorphous carbons into the crystalline semi-graphite and graphite like functional materials. In this report, the XRD spectroscopy is applied to the variably carbonized and graphitized carbon materials (activated carbons (AC1─AC3) & carbon blacks (CB1─CB4)), and the progressive internal improvisations in their graphene layouts caused by the dissimilar metamorphic temperature regimes are sought out. For this, the XRD diffractograms linked descriptors (diffraction angles (\(2\theta\)), intergraphene layer gap (d), & crystallite sizes (Lc)), and the correlations between many descriptive subordinates (% crystallinity (%C), graphitization degree (%DOG), metamorphic temperature (Tmet), BET surface area (SBET), and specific capacitance (CSP)) are taken into account. The former set speculates the existence of lower amorphicity and higher graphitic homogeneity in CBs than in the ACs, and elucidates their contrasting inbound graphene configurations. And, the latter set quantifies the extent to which the founding graphitic units of them undergo significant improvements owing to acquire better functional domains. The applicative propensities for them are forecasted as CB4 (C = 1.3%, DOG = 98%, Tmet = 595⁰C, SBET = 5348 m2/g, CSP = 600 F/g) > CB3 (C = 5.1%, DOG = 96%, Tmet = 588⁰C, SBET = 3735 m2/g, CSP = 419 F/g) > CB2 (C = 5.8%, DOG = 93%, Tmet = 576⁰C, SBET =1508 m2/g, CSP = 169 F/g) > CB1 (C = 19.7%, DOG = 64%, Tmet = 486⁰C, SBET = 1186 m2/g, CSP = 133 F/g). The author believes these datasets as quite useful while specifying their compressibility & reinforcement, binding & lubricity, catalysts & catalysis, electrochemical & electro-adsorption, etc., and can be referred time to time while identifying distinctive functionalities of one over the others.