Multifunctional SnO2-@ doped glass fiber-reinforced concrete: Improved microstructure, mechanical, dielectric, and energy storage characteristics

This study explores SnO2-based hybrid composite (SnO2-@) doped glass fiber-reinforced concrete (GFRC) for enhanced dielectric, energy storage, and mechanical performance. Microstructural analysis confirmed SnO2-@ promotes ettringite and calcium silicate hydrate (C-S-H) formation, improving matrix integrity. Aged samples exhibited a 650 % increase in surface roughness (Ra) and over 200 % higher Leeb hardness, demonstrating durability. Dielectric spectroscopy revealed frequency-dependent tunability: 1 % SnO2-@ achieved a peak dielectric constant (8' =130 at 10 kHz), shifting to 8' =140 at 100 kHz for 2-3 % doping. AC conductivity surged by 60 %, correlating with SnO2-@-induced interfacial polarization and charge mobility. Energy storage capacity improved significantly, attributed to optimized dipole alignment and reduced leakage currents. Color stability remained robust (Delta E* <= 2.8 post-aging), ensuring aesthetic viability. These results position SnO2-@-doped GFRC as a multifunctional material for smart infrastructure, integrating structural resilience, adaptive dielectric properties, and energy storage potential for next-generation urban applications.