Solid-State Synthesis of Nanosized LiFePO4 Cathode Material by Using a Diluting Agent Kamila Akhmetova, Batukhan Tatykayev, Zhandos Shalabayev, Natalya Khan, Fail Sultanov, Valeriya Volobuyeva, Akbar Dauletbay, Zhumabay Bakenov, Almagul Mentbayeva ACS Applied Energy Materials, 2025 Nanosized LiFePO 4 /C cathode material was synthesized via a facile mechanochemical activation method with the addition of a diluting agent. A diluting agent or solid diluent is an inert additive that does not react with the precursors and can be easily removed after synthesis by washing or heating. Its addition promotes the formation of nanoparticles with minimal or no agglomeration. In this study, (NH 4 ) 2 CO 3 was selected as the solid diluent for synthesizing LiFePO 4 /C nanoparticles. The structure, surface morphology, and electrochemical performance of the synthesized material were characterized using thermogravimetric analysis coupled with mass spectrometry, X-ray diffraction, X-ray photoelectron spectroscopy, electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge/discharge testing. Fourier-transform infrared and Raman spectroscopy has confirmed the formation of an intermediate complex after mechanochemical activation. The use of a solid diluent up to a certain concentration was found to effectively reduce the particle size. The optimal diluent amount was determined to be 0.2 g per 1 g of LiFePO 4 /C, resulting in particles smaller than 100 nm. This sample exhibited excellent electrochemical performance, comparable to commercial LiFePO 4 /C, with a discharge capacity of 144.48 mAh g –1 at 0.1C and 100% capacity retention after 30 cycles.
Sustainable Scalable Mechanochemical Synthesis of CdS/Bi2S3 Nanocomposites for Efficient Hydrogen Evolution Zhandos Shalabayev, Abylay Abilkhan, Natalya Khan, Saparbek Tugelbay, Anar Seisembekova, Batukhan Tatykayev, Matej Balaz Nanomaterials, 2024 In the present study, a green, scalable, and environmentally friendly approach was developed for the fabrication of Bi2S3-decorated CdS nanoparticles with an efficient hydrogen generation ability from the water. As a sulfur source, thiourea was used. The process was completed in two stages: mechanical activation and thermal annealing. The presence of spherical CdS nanoparticles and Bi2S3 nanorods in the CdS/Bi2S3 nanocomposite was confirmed and proved by XRD, Raman spectroscopy, SEM-EDS, and TEM. The synthesized CdS/Bi2S3 nanocomposites were evaluated for their photocatalytic hydrogen evolution capabilities. The CdS/Bi2S3 photocatalyst exhibited 25% higher photocatalytic activity compared to CdS, reaching a hydrogen evolution rate of 996.68 μmol h−1g−1 (AQE 0.87%) after 3.5 h under solar-light irradiation.
The superiority of the photocatalytic and antibacterial performance of mechanochemically synthesized CdS nanoparticles over solvothermal-prepared ones Gairat Burashev, Batukhan Tatykayev, Matej Baláž, Natalya Khan, Ardak Jumagazieva, Zhanar Iskakbayeva, Anar Seysembekova, Saparbek Tugelbay, Nurshat Turgynbay, Almagul Niyazbayeva, Aleksandr Ilin, Mukhambetkali Burkitbayev, Zhandos Shalabayev Semiconductor Science and Technology, 2024 In this work, we have developed a facile, dry, and environmentally friendly mechanochemical method for the synthesis of cadmium sulfide (m-CdS) nanoparticles in a planetary ball mill using non-toxic precursors. Thiourea was for the first time used as a precursor of sulfide ion in room temperature solid state ball milling synthesis. For comparison of the mechanochemical approach with others, cadmium sulfide nanoparticles were also prepared using the solvothermal method (s-CdS). The crystal structure of cadmium sulfide nanoparticles was studied by XRD, the qualitative chemical band properties were examined by Raman scattering and x-ray photoelectron spectroscopy analysis, and particle morphology and microstructure were investigated by scanning electron microscopy and transmission electron microscopy methods. The sizes of the m-CdS nanoparticles had 5–6 nm in diameter, which is 10 times smaller than the diameter of s-CdS nanorods. The photocatalytic activities of as-prepared cadmium sulfide nanoparticles on the dye degradation and hydrogen production by water splitting were evaluated and the antibacterial activities were also tested. The photocatalytic activity of m-CdS was superior to that of s-CdS in the degradation of Orange II under visible light irradiation. Better results for m-CdS were also evidenced in photocatalytic experiments on hydrogen generation. The maximum rate of hydrogen evolution for m-CdS was 191.9 µmolg−1h−1 at the 120th min,while this indicator for s-CdS was only 58.0 µmolg−1h−1 at the same irradiation time.The better effect of m-CdS was evidenced also in an antibacterial study (namely against gram-positive bacteria).