Innovative materials for energy storage devices and energy efficiency are crucial for advancing sustainable technology. This thesis investigates innovative approaches using advanced polymer blends to enhance the performance and sustainability of thermochromic windows and electrochemical energy storage systems. The primary focus is on a mixed polymer system composed of poly(dimethyl siloxane), poly(ethylene oxide), and an alkali salt. The development of a three component thermochromic polymer blend capable of dynamically adjusting transparency in response to external temperatures significantly improves the energy efficiency of HVAC systems in buildings by controlling solar radiation influx. This material presents a promising solution for reducing energy consumption in architectural applications. The thermochromic properties are characterized by the blend's ability to switch between transparent and light-blocking states at specific temperature thresholds. The blend's stability, durability, and responsiveness are tested under various environmental conditions to ensure long-term performance and reliability. In addition to the thermochromic applications, the ionic conduction properties of lithium, sodium, and magnesium ions within the polymer matrix are explored. Enhanced room-temperature ionic conductivity is achieved, leading to the development of safer and more efficient solid-state electrolytes for ion batteries. The thesis also introduces a novel hydrothermal method for the low-temperature transformation of amorphous fused silica into crystalline α-quartz. Facilitated by sodalime glass and sodium ion migration, this process offers a sustainable and energy-efficient approach to material synthesis, significantly reducing the energy requirements compared to traditional high-temperature methods. The potential of advanced polymer blends, particularly in thermochromic smart windows, to contribute to energy-efficient buildings and electrochemical applications is significant. The findings have broad implications for industries such as electronics, optics, and materials engineering, underscoring the importance of innovative materials and methods in advancing sustainable technology.