Applications of Density Functional Theory in Modern Materials Research

Abstract: Density Functional Theory (DFT) is currently one of the most powerful and widely employed quantum mechanical methods in modern materials science, condensed matter physics, and computational chemistry. Due to its capability to accurately describe the electronic structure of materials at the atomic level with relatively moderate computational cost, DFT has become an essential theoretical framework for investigating a broadA range of advanced materials. In recent decades, DFT has played a central role in the study of nanomaterials, two-dimensional materials, semiconductors, magnetic materials, catalysts, and optoelectronic systems. The method enables researchers to predict and analyze important physical and chemicalproperties, including electronic band structures, density of states, magnetic behavior, optical responses, adsorption mechanisms, and thermodynamic stability. This review summarizes the fundamental principles of DFT, including the Hohenberg–Kohn theorems and Kohn–Sham formalism, together with commonly used exchange–correlation approximations such as LDA, GGA, hybrid functionals, and DFT+U methods. Furthermore, important applications of DFT in gas sensing, energy storage, photocatalysis, and novel material design are discussed in detail. The advantages and limitations of DFT are also highlighted, particularly regarding band-gap prediction and strongly correlated systems. Finally, future development trends of DFT are presented in the context of artificial intelligence, machine learning, high-performance computing, and large-scale materials discovery.