▎ 摘　　要

NOVELTY - Vulcanized anthracene-based polymer i.e. 1,2,3,4,5,6,7,8-octasulfanyl-9,10-dihydroanthracene-9,10-dithione compound (I) is new. USE - (I) is useful as active material in the anode of magnesium secondary batteries (all claimed). ADVANTAGE - (I) has excellent thermal stability, insoluble in electrolyte solvent, and achieves high reversible, fast magnesium ions (Mg2+) storage and high power density; the method has simple operation, and controllable conditions. DETAILED DESCRIPTION - Vulcanized anthracene-based polymer i.e. 1,2,3,4,5,6,7,8-octasulfanyl-9,10-dihydroanthracene-9,10-dithione compound of formula (I) is new, where (I) has complete conjugated fused anthracene skeleton, each anthracene skeleton unit is connected through sulfur chain or directly through the carbon of fused ring anthracene and is saturated with sulfur chain, and the sulfur chain is =S=, -S- or -S-S-. Wavy line = connecting bond between each repeating unit. Provided that: The number of repeating unit is 2-10. INDEPENDENT CLAIMS are also included for: Preparation of (I); Use of (I) as an active material in the anode of magnesium battery, comprising dispersing (I), conductive agent, and adhesive uniformly in a solvent as anode slurry, then coating it on the current collector uniformly and vacuum drying to obtain anode of magnesium battery, where the anode of magnesium battery includes current collector and active material layer coated on at least one side surface of current collector, and the active material layer includes (I); and Magnesium secondary battery, comprising self-assembling anode and cathode of magnesium battery, electrolyte and membrane.