▎ 摘　　要

The desire for practical utilization of rechargeable lithium batteries with high energy density has motivated attempts to develop new electrode materials and battery systems. Here, without additional binders we present a simple vacuum filtration method to synthesize [GRAPHICS] nitrogen and sulfur codoped graphene (N,S-G) blocking layer, which is ultra-lightweight, conductive, and free standing. When the N,S-G membrane was inserted between the catholyte and separator, the lithium-selenium (Li-Se) batteries exhibited a high reversible discharge capacity of 330.7 mAh g(-1) at 1 C (1 C = 675 mA g(-1)) after 500 cycles and high rate performance (over 310 mAh g(-1) at 4 C) even at an active material loading as high as similar to 5 mg cm(-2). This excellent performance can be ascribed to homogenous dispersion of the liquid active material in the electrode, good Li+-ion conductivity, fast electronic transport in the conductive graphene framework, and strong chemical confinement of polyselenides by nitrogen and sulfur atoms. More importantly, it is a promising strategy for enhancing the energy density of Li-Se batteries by using the catholyte with a lightweight heteroatom doping carbon matrix.