Hole Transport Layers for Organic Solar Cells: Recent Progress and Perspectives
As a new generation of solid-state film cells, the organic solar cells (OSCs) have become the research focus in the field of renewable energy sources, and the reported power conversion efficiencies (PCEs) have been boosted to 18%. The hole transport layer (HTL) materials, a critical component of the OSCs, exert a tremendous impact on the PCE and stability of the OSCs. At present, the HTL materials used in OSCs can be divided into two main categories, which are inorganic HTL materials and organic HTL materials. Although, the OSCs with inorganic HTL materials can achieve satisfied PCE, they are not suitable for the large-scale commercial roll-to-roll production due to the unavoidable process of high-temperature vacuum evaporation. Recently, a great number of organic HTL materials have been designed, synthesized, and successfully applied in the OSCs. Herein, we review the recent advances of organic HTL materials in single-junction OSCs and systematically discuss the relationships between the structure and properties of various HTL materials, and highlight the designing rules of HTL materials to toward highly efficient and stable OSCs.
- This article is part of the themed collection: Journal of Materials Chemistry A Recent Review Articles