Toward Efficient Photoelectric Conversion: A Perspective on Interfacial Engineering of TMDC Heterojunctions

Transition metal dichalcogenide (TMDC) heterojunctions exhibit high light absorption and fast carrier transport for developing promising applications in optoelectronic devices. Interfacial engineering enhances the built-in electric field (BEF) by optimizing energy band alignment, designing heterojunction architectures, and regulating interfacial defect states, thereby enabling rapid carrier separation and transport. This review provides a comprehensive overview of recent advances in interfacial engineering toward efficient photoelectric conversion for photodetectors. First, heterojunction fabrication techniques such as transfer stacking and direct growth are systematically described. The mechanisms of three strategies (energy band engineering, structural engineering, and defect engineering) to manipulate carrier distribution are discussed. These approaches are tailored to enhance carrier transport, suppress carrier nonradiative recombination, and ensure effective carrier transfer to the electrodes. Subsequently, the applications and limitations of TMDC heterojunctions in optoelectronic devices are discussed and analyzed. Finally, we discuss current challenges, future opportunities, and development perspectives for interfacial modulation in TMDC heterojunctions. This review aims to effectively guide readers in understanding, designing, and leveraging interfacial engineering to achieve high-performance optoelectronic devices.