Two novel 2-D bamboo-raft-like lanthanide luminescent materials [Ln(Himc)(SO4)(H2O)] (Ln = Dy, Eu; H2imc = 4-imidazolecarboxylic acid), constructed from alternate left- and right-handed helical tubes, were synthesized and characterized; interestingly, H2imc came from the in situ decarboxylation of the 4,5-imidazoledicarboxylic acid (H3imdc) in the hydrothermal reactions.