A novel approach to the synthesis of silicocarnotite

In this letter, we present a new approach to the synthesis of silicocarnotite - a promising bioceramic material. This approach is based on selecting a precursor with a crystalline structure close to that of silicocarnotite in an attempt to reduce the transformation temperatures. In the synthesis route that we suggest, silicocarnotite forms from mechanochemically synthesized nanosized silicon-substituted apatite. The main advantages of this route are lower temperatures and shorter annealing times required for the synthesis of the target phase in. comparison with the direct solid-state synthesis, aqueous precipitation or sol-gel method. It was shown that the silicocarnotite phase is obtainable by annealing the mechanochemically synthesized silicon-substituted apatite for 5 h at a temperature as low as 1000 degrees C. According to the differential scanning calorimetry, the phase transition from silicon-substituted apatite to silicocarnotite occurs at 970 degrees C. In this work, complete assignment of the absorption bands of the IR spectrum of silicocarnotite to particular bond vibrations is reported for the first time. (C) 2015 Elsevier B.V. All rights reserved.