A novel yttrium citrate-templated conversion method for morphology controlled synthesis ofY2O3 microspheres,microflowers and microsheets was reported for the first time.The precursors with controllable morphologies were synthesized with a homogenous precipitation method in aqueous solution without any surfactant.Y2O3 samples with well-preserved morphological architectures were obtained by a subsequent thermal transformation strategy.The chemical formula of the precursor was identified and a two-stage growth mechanism was proposed.The effects of the aging time,reaction temperature,reactant concentration and molar ratio of yttrium nitrate to sodium citrate were discussed.The photoluminescence properties of the Y2O3∶Eu3+ microspheres,microflowers and microsheets prepared were also studied.