کنفرانس مهندسی برق ایران

صفحه اصلی / سی و چهارمین کنفرانس بین المللی مهندسی برق

Tunable Band gap of Beta Zeolite by Adjusting the Si/Al Ratio

نویسندگان :

Reza Goldoust¹ Saeideh Rahbarpour²

1- Shahed University 2- Shahed University

کلمات کلیدی :

Zeolite Beta،Electronic material،DFT،DOS،Si/Al ratio،Sensor

چکیده :

Zeolites, as porous materials at the molecular scale, are extensively employed as “molecular sieves” in various applications owing to their high selectivity and regular channel structure, with ~250 types identified to date. However, the large band gap and insulating nature of zeolites have restricted their utilization as active electronic materials in sensors. This study demonstrates that decreasing the Si/Al ratio in the framework of Beta zeolite reduces the band gap, thereby transitioning the material from an insulating to a semiconducting behavior. To this end, a computational investigation based on density functional theory was conducted, in which the structure of Beta zeolite in the fully siliceous type (Si/Al = ∞) and at various Si/Al ratios—including 63, 20.1, 11.8, 6.1, 3, and 1.8—was optimized. Their electronic properties, encompassing band structure, density of states, and charge distribution, were analyzed. The results reveal that decreasing the Si/Al ratio reduces the band gap from ~6.1 eV to ~4.4 eV. A key finding is that the engineered Beta zeolite becomes an active material that integrally provides both sensing and catalytic functions, thereby circumventing challenges associated with combining two distinct materials, such as thermal coupling issues and reduced diffusion rates.