This thesis focuses on the design, synthesis and application of 3d metal chalcogenides (MCs) and grafting-related hybrid materials as new, inexpensive and efficient electrocatalysts. It discusses the pioneering results in the study of noble-metal alternative electrocatalysts, addressing the following aspects: (i) Presenting a robust molecule template strategy to access high-class 3d MCs. (ii) Introducing a materials grafting concept that produces a group of new CoSe2-based hybrid materials by taking the lamellar CoSe2 nanobelts as a typical representative. (iii) Reporting on the important applications of these hybrids for ORR, OER and HER. The prepared nanostructured 3d metal chalcogenides (3d MCs) and resultant hybrids exhibit high activity and stability for catalyzing several important and difficult reactions including oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). These inexpensive materials hold great promise to replace the rare and expensive catalysts (i.e., Pt, RuO2, IrO2 etc.) currently used in fuel cells and electrolyzers, and may accelerate the commercialization of these clean technologies.