CORRELATION BETWEEN SURFACE MICRO-TEXTURE AND ELECTRICAL RESISTIVITY IN CORN HUSK-DERIVED BIOMASS CARBON FOR HIGH-PERFORMANCE ENERGY APPLICATIONS

The escalating global emphasis on sustainable materials has directed considerable research toward agricultural residues as viable precursors for functional carbon materials. This study examines the correlation between surface micro-texture and electrical resistivity in corn husk-derived samples across three processing stages: raw corn husk (RH), carbonized corn husk (CH), and chemically activated corn husk carbon (ACH). Surface roughness parameters, including arithmetic average roughness (Ra), root mean square roughness (Rq), and total peak-to-valley height (Rt), were quantified using profilometry, while electrical resistivity was measured via the four-point probe method. The results indicate a pronounced inverse relationship, with roughness increasing progressively from RH (Ra = 3.85 µm, ρ = 1280 Ω·cm) to ACH (Ra = 9.76 µm, ρ = 95 Ω·cm) concomitant with carbonization and chemical activation, thereby enhancing electrical conductivity. Nonlinear regression models, such as exponential decay and power-law functions, provided excellent fits to the data (R² > 0.995), underscoring the role of hierarchical porosity and textured surfaces in facilitating improved electron transport pathways. These findings offer insights for the rational design of biomass-derived carbons suitable for applications in supercapacitors and other energy storage systems.