Liquid nitrogen post-treatment for improved aggregation and electrical properties in organic semiconductors

Abstract

Organic semiconductors are promising candidates as active layers in flexible and biocompatible electronics owing to their solution processability and molecular design flexibility. However, it remains necessary to establish a green processing approach to acquire desirable electrical properties for scalable industrial applications. Here, a highly efficient and environmentally friendly post-treatment method using liquid nitrogen as a cooling bath is developed to optimize the aggregation structure and electrical performance of organic semiconductors. The carrier mobility has increased by nearly 60% with this treatment, achieving a performance boost comparable to that of traditional annealing methods. This performance improvement is attributable to the denser aggregation structure and enhanced molecular ordering compared with those of as-cast semiconducting polymer films. Impressively, the entire process can be completed within a few minutes without additional vacuum or high-temperature conditions, offering an economical and efficient alternative to traditional methods. Furthermore, the enhancement effect and long-term stability of this treatment are validated across a wide range of organic semiconductors, positioning this green and versatile approach as a promising substitute for conventional post-treatment, thereby facilitating the development of next-generation sustainable electronics.