TY - JOUR

T1 - Low temperature synthesis and high temperature behavior of feldspar-like CdAl2Si2O8, a promising material for cadmium immobilization

AU - Верещагин, Олег Сергеевич

AU - Горелова, Людмила Александровна

AU - Кржижановская, Мария Георгиевна

AU - Юхно, Валентина Анатольевна

AU - Шорец, Ольга Юрьевна

PY - 2025/8/1

Y1 - 2025/8/1

N2 - Cadmium is an extremely toxic nonbiodegradable heavy metal, which accumulates in significant quantities in the near-surface environments, where it easily enters surrounding water and soil. In this work, we synthesized a series of cadmium silicates (CdAl2Si2O8, Cd2SiO4, Cd3Si3O9, Cd3(SiO4)O), which are prospective materials for cadmium immobilization. The most environmentally stable and least studied of them, CdAl2Si2O8, was investigated by means of scanning electron microscopy, energy-dispersive X-ray spectroscopy, powder and single crystal X-ray diffraction (over the temperature range of 27–1100 °C). Using alkali cations additives, we were able to obtain CdAl2Si2O8 at a temperature (500 °C) half previously reported. We showed that cadmium can be successfully incorporated into a feldspar-like crystal structure and that the amount of cadmium could range depending on synthesis conditions from 21 to 37 wt % CdO. Our data indicate that CdAl2Si2O8 is stable up to at least 1100 °C and does not undergo phase transitions with a change in the volume of the unit cell. We can conclude that CdAl2Si2O8 is a promising material for cadmium immobilization, given its resistance to leaching and low synthesis temperatures.

AB - Cadmium is an extremely toxic nonbiodegradable heavy metal, which accumulates in significant quantities in the near-surface environments, where it easily enters surrounding water and soil. In this work, we synthesized a series of cadmium silicates (CdAl2Si2O8, Cd2SiO4, Cd3Si3O9, Cd3(SiO4)O), which are prospective materials for cadmium immobilization. The most environmentally stable and least studied of them, CdAl2Si2O8, was investigated by means of scanning electron microscopy, energy-dispersive X-ray spectroscopy, powder and single crystal X-ray diffraction (over the temperature range of 27–1100 °C). Using alkali cations additives, we were able to obtain CdAl2Si2O8 at a temperature (500 °C) half previously reported. We showed that cadmium can be successfully incorporated into a feldspar-like crystal structure and that the amount of cadmium could range depending on synthesis conditions from 21 to 37 wt % CdO. Our data indicate that CdAl2Si2O8 is stable up to at least 1100 °C and does not undergo phase transitions with a change in the volume of the unit cell. We can conclude that CdAl2Si2O8 is a promising material for cadmium immobilization, given its resistance to leaching and low synthesis temperatures.

KW - Cadmium

KW - CdAl2Si2O8

KW - Feldspar

KW - High temperature

KW - X-ray

UR - https://www.mendeley.com/catalogue/1437ffe7-9557-3e9a-a47a-8a6409819fa9/

U2 - 10.1016/j.jssc.2025.125411

DO - 10.1016/j.jssc.2025.125411

M3 - Article

VL - 348

JO - Journal of Solid State Chemistry

JF - Journal of Solid State Chemistry

SN - 0022-4596

IS - 348

M1 - 125411

ER -