In this paper, the development of ionic liquids as stationary phases for gas chromatography is briefly described. In order to improve the thermal stability, selectivity and column efficiency of ionic liquid stationary phases, the synthesis methods of ionic liquid stationary phases with achiral selectivity are developed successively, including small molecule ionic liquids, bulky ionic liquids, polymeric ionic liquids, physical mixed ionic liquids and chemically bonded ionic liquids. Meanwhile, ionic liquids are applied in chiral gas chromatography, employed as the solvent of chiral selectors or as chiral stationary phases of gas chromatography. Chiral pools of these ionic liquids are mostly from amino acids, chiral amines and bonded cyclodextrins. The differences in selectivity of these ionic liquid stationary phases are also discussed and reviewed. Then, the application of ionic liquids in two-dimensional gas chromatography and fast gas chromatography are introduced. Finally, the synthesis and application of ionic liquids in gas chromatography are summarized. The prospects of ionic liquid as novel separation materials are also discussed and forecasted.

Contents
1 Introduction
2 Ionic liquids with common selectivity as stationary phases for gas chromatography
2.1 Stationary phases based on small molecule ionic liquids
2.2 Stationary phases based on polymerized ionic liquids in column
2.3 Stationary phases based on physical mixed ionic liquids
2.4 Stationary phases based on chemically bonded ionic liquids
3 Ionic liquids with chiral selectivity as stationary phases for gas chromatography
3.1 Ionic liquids as chiral stationary phase solvents
3.2 Chiral ionic liquids as stationary phases
4 Ionic liquids as stationary phases for other gas chromatography
4.1 Ionic liquids as stationary phases for two-dimensional gas chromatography
4.2 Ionic liquids as stationary phases for fast gas chromatography
5 Conclusions