The development of high-efficiency, stable and low-cost luminescent materials and devices is one of the most effective ways to achieve efficient use of energy, and is an important guarantee for our country's transition to a low-carbon economy. Metal-halide perovskites possess the advantages of both inorganic and organic materials, and have great potential for low-cost, large-area, flexible display and lighting applications. The core of the work of perovskite light-emitting devices is the carrier dynamics of the functional layer under the driving of electric/optical field. Therefore, the detection, understanding and manipulation the carrier dynamics in perovskite by tailoring the materials’ dimensionality and size are the key scientific issues in this field.