Self-assembly enables simple structure organic photovoltaics via green-solvent and open-air-printing: Closing the lab-to-fab gap

The ultimate goal of organic solar cells (OSCs) is to deliver cheap, stable, efficient, scalable, and eco-friendly solar-to-power products contributing to the global carbon neutral. However, simultaneously balancing these five critical factors of OSCs toward commercialization is extremely challenging. Herein, a green-solvent-processable and open-air-printable self-assembly strategy is demonstrated to synchronously simplify the device architecture, improve the power conversion efficiency (PCE) and enhance the shelf, thermal as well as light illumination stability of OSCs. The cathode interlayer (CIL)-free self-assembled OSCs exhibit the PCE of 15.5%, higher than that of traditional inverted OSCs of 13.0%, which is among the top values for both CIL-free self-assembled OSCs and open-air blade-coated bulk-heterojunction OSCs. The remarkable enhancements are mainly ascribed to the finely selfassembly, subtly controlled donor/acceptor aggregation rate, and delicately manipulated vertical morphology. Besides, this strategy enables 13.2% efficiency on device area of 0.98 cm(2), implying its potential for scalability. These findings demonstrate that this strategy can close the lab-to-fab gap of OSCs toward commercialized cheap, stable, efficient, scalable, and eco-friendly OSCs

Multi-Level Support Technology and Application of Deep Roadway Surrounding Rock in the Suncun Coal Mine, China

To solve these problems of poor supporting effect and serious deformation and failure of surrounding rock of mining roadway under deep mining stress, a FLAC-3D numerical calculation model is established with −800 m level no. 2424 upper roadway in the Suncun Coal Mine as the background to compare the stress, deformation, and failure law of surrounding rock of mining roadway under once support and multi-level support with the same support strength. It is found that the multi-level support technology has obvious advantages in the surrounding rock of the horizontal roadway on the 2424 working face. From this, the key parameters of multi-level support are determined, and the field industrial test is carried out. The results show that the overall deformation of the surrounding rock is obviously reduced after multi-level support. The displacement of the two sides is reduced by about 40%, the displacement of the roof and floor is reduced by about 30%, and the plastic zone of the roadway is reduced by about 75%. The peak value of concentrated stress decreases from 98.7 MPa to 95.8 MPa, which decreases slightly. The integrity and stability of the surrounding rock are excellent, and the support effect is satisfactory. The research can provide reference and technical support for surrounding rock control of deep high-stress mining roadways