Combined Experimental and Computational Prediction of the Piezoresistivity of Alkali-Activated Inorganic Polymers

The incorporation of smart building materials into construction will improve the working life of structures and infrastructure around the globe. Unfortunately, conventional smart building materials are cost-prohibitive because of the self-sensing additives required. Alkali-activated inorganic polymers are a promising low-cost and environmentally friendly alternative that exhibit intrinsic self-sensing properties, without the need for self-sensing additives. An improved methodology has been developed to quantify the self-sensing piezoresistivity of these materials. Experimental measurements reveal a strong intrinsic piezoresistivity up to 12%. The results agree with a first-principles model of the theoretical piezoresistivity of an alkali-activated inorganic polymer from the quantum mechanical perturbation theory. This first-of-its-kind computation provides a mechanistic explanation for the origin of intrinsic piezoresistivity in inorganic polymers.