ELECTRONIC BAND STRUCTURE ENGINEERING OF TWO-DIMENSIONAL MATERIALS FOR HIGH-PERFORMANCE DEVICES

Abstract

Two-dimensional (2D) materials have emerged as a cornerstone for next-generation nanoelectronics and optoelectronics, offering atomically thin channels, exceptional carrier mobilities, and unprecedented tunability of electronic band structures. This review comprehensively examines strategies for engineering the band structure of representative 2D systems including graphene and Xenes, transition metal dichalcogenides (TMDs), black phosphorus, and MXenes to overcome the limitations of conventional silicon-based devices in the sub-10 nm regime. Key approaches include straintronics (mechanical deformation inducing direct-to-indirect transitions and bandgap shifts of up to 100 meV per % strain), twistronics and moiré superlattice engineering (realization of flat bands, correlated states, unconventional superconductivity, and moiré excitons at magic angles), surface functionalization and charge-transfer doping (precise control of carrier type and density), and valleytronic manipulation (exploitation of spin-valley locking and Berry curvature dipoles for low-power information processing). These techniques enable high-performance field-effect transistors with on/off ratios exceeding 10⁸, subthreshold swings approaching the 60 mV/decade limit, ultra-sensitive photodetectors (responsivities >10⁵ A/W), and flexible energy-storage devices. Artificial intelligence-driven inverse design and high-throughput computational screening accelerate discovery of novel 2D phases and optimized heterostructures. Despite remarkable laboratory demonstrations, challenges in large-area synthesis, environmental stability, reliable transfer processes, and reproducible moiré-angle control remain critical barriers to commercialization. Addressing these bottlenecks through advances in direct-growth methods, robust encapsulation, and scalable strain/twist engineering will be essential to realize the full potential of band-structure-engineered 2D materials in energy-efficient logic, quantum devices, and wearable technologies.