Search

Molecular semiconductors (MSCs) are known as ideal candidates for constructing room‐temperature spin‐charge interactive devices due to their long spin lifetimes and abundant photoelectric properties. These devices can achieve novel and valuable functionalities such as room‐temperature supply units of fully spin‐polarized current. Unfortunately, their performances (sub‐0.1 nA) remain unsatisfactory due to limited charge and spin injection efficiency, which can hardly be improved despite great efforts thus far. Herein, from the theoretical side, an interfacial tunnel layer with precisely‐controlled barrier in spintronic devices may simultaneously enhance spin and charge injection. Accordingly, a solution‐processed small molecule with smooth morphology and amorphous structure is introduced to form a uniform and well‐controllable barrier in molecular spin‐photovoltaic devices. By modulating the thickness to effectively control the barrier, both spin and charge injection efficiency increase by > 150%. Thus, the spin‐charge interactive functionalities as supply units of fully spin‐polarized current have also been significantly improved than the current record at room temperature, the output fully spin‐polarized current (>2 nA) is 1200%‐larger, and the output power increases by > 50 times. Moreover, the interface‐modified spintronic devices exhibit excellent stability even after 70 days of exposure to air, which is essential for practical applications in the future. [ABSTRACT FROM AUTHOR]

Metal halide perovskite light‐emitting diodes (PeLEDs) are gaining increasing attention as a promising candidate for the new‐generation display technology. Although tremendous progress has been witnessed in this field, the device performance of blue PeLEDs still lags far behind that of the green and red counterparts. In this work, an effective interfacial engineering is employed to boost the radiative recombination of blue perovskite film by introducing a multifunctional tetraethyl orthosilicate (TEOS) network on the grain‐growth substrate. Benefitting from the strong interaction between the TEOS molecule and perovskite nuclei, the perovskite crystallization dynamics are effectively regulated, contributing to significantly improved emitting film with uniformly distributed halogen and concentrated low‐dimensional domain. Additionally, the TEOS network can distinctly passivate the crystal defects at the buried perovskite interface owing to its adequate electron‐donating sites. Consequently, the target blue PeLEDs featuring a stable emission peak at 488 nm exhibit a champion external quantum efficiency of 17.3%, which is among the highest values to date. The results demonstrate the critical role of the surface molecular characteristics of the grain‐growth substrate in regulating the mixed‐halide blue perovskite crystallization. [ABSTRACT FROM AUTHOR]