Traditional long-persistent luminescence (LPL) materials, which are based on inorganic systems containing rare elements and with preparation temperatures of at least 1000 °C, exhibit afterglow times of more than 10 h and can be tuned for different applications. However, the development of this field is hindered due to the large thermal energy consumption and the need for nonrenewable resources. Thus, the development of a "green" design and preparation of LPL materials is of some importance. A doped-crystalline material based on two metal-free organic small molecules is easily prepared through ultrasonic crystallization at room temperature. It has a high-quality, singlecrystalline structure, and visible LPL performance with a duration of more than 6 s upon low-energy photoexcitation. A green, flexible, and convenient screen-printing technology for controllable pattern anticounterfeiting is then developed from this purely organic material, which improves the prospects for commercial utilization in the future.

A h‐BN self‐aligned single‐crystal array (SASCA) that exhibits orderly alignment and uniformly distribution is controllably synthesized on a liquid Cu surface for the first time. The h‐BN SASCA exhibits highly accordant spatial orientation and homogenous domain size, which can realize highly integrated and individually switching field‐effect transistors when serving as a gate dielectric. Circular h‐BN single‐crystals, which are considered to be the building blocks of h‐BN SASCA, are also observed.

Anodization is a promising technique to form high- k dielectrics for low-power organic field-effect transistor (OFET) applications. However, the surface quality of the dielectric, which is mainly inherited from the metal electrode, can be improved further than other fabrication techniques, such as sol-gel. In this study, we applied the template stripping method to fabricate a low-power single-crystalline OFET based on the anodized AlO dielectric. We found that the template stripping method largely improves the surface roughness of the deposited Al and allows for the formation of a high-quality AlO high- k dielectric by anodization. The ultraflat AlO /SAM dielectric combined with a single-crystal 2,6-diphenylanthracene (DPA) semiconductor produced a nearly defect-free interface with a steep subthreshold swing (SS) of 66 mV/decade. The current device is a promising candidate for future ultralow-power applications. Other than metal deposition, template stripping could provide a general approach to improve thin-film quality for many other types of materials and processes.