The invention relates to multi-atomic layer borophene and a method of synthesizing multi-atomic layer borophene. The multi-atomic layer borophene comprises bilayer (BL) borophene. The BL borophene is BL-α borophene comprising two covalently bonded α-phase borophene monolayers and being metallic and in form of a highly faceted island with a six-fold symmetric Moiré superlattice surrounded by full-coverage intermixed SL v1/5 and v1/6 borophene. The BL-α borophene nucleates and emerges at intersections of multiple SL borophene domains. The synthesizing method includes depositing boron on a substrate with atomically flat terraces at a temperature in an ultrahigh vacuum (UHV) chamber to grow multi-atomic layer borophene beyond a full coverage of single-atomic layer (SL) borophene.