| dc.description.abstract | Preparation of silica from rice husks with variations calcination of 600oC,
700oC, 800oC, and 900oC and added NaOH then added HCl until pH 7. It was filtered
and dried to obtain silica. FTIR characterization showed OH vibration 3398.28 cm-
1 - 3404.23 cm-1, OH bending 1065.57 cm-1 - 1637.07 cm-1, Si-O-Si asymmetry
1065.57 cm-1 - 1061.67 cm-1, Si-OH 795.93 cm-1 - 796.41 cm-1, and O-Si-O 445.51
cm-1 - 448.66 cm-1. XRD characterization showed 2θ at 27.31o - 27.33o, 31.65o -
42.69o, and 45.39o - 45.45o. XRF characterization showed silica of 44.5% - 39.5%.
Silica was added KBr solution and then ultrasonicated to reduce the particle size to
nano-sized. KBr was used as a scavenger agent when reducing the magnesiothermic
method. It was purified to obtain silicon nanoparticles. Raman spectroscopic show
520.09 cm-1 - 520.14 cm-1. XRD characterization showed 2θ at 26.44o - 26.46o,
47.29o - 47.32o, 56.10o - 56.13o, 69.12o - 69.15o, 76.37o - 76.40o and 88.01o - 88 ,03o.
The RIR method shows the silicon content of 88.10% – 95.40%. XPS characterization
shows Si+, Si2+, Si3+, and Si4+. SAA characterization showed surface area of 14.59
m2/g - 14.61 m2/g, pore volume of 0.03 cc/g, and pore size of 1.69 nm. SEM and TEM
characterization of spherical shape and EDX showed 99.05% - 99.05% silicon
content. Silicon nanoparticles were applied as anodes in lithium-ion batteries.
Preparation electrodes with the addition of silicon nanoparticles, polyacrylic
acid/sodium alginate, and acetylene black. Assembly of lithium-ion with swagelok
type cell with lithium iron phosphate as cathode, Whatman microglass as separator,
and silicon nanoparticles as anode. The CV show lithiation 0.16 V - 0.25 V and
delithiation 0.54 V - 0.87 V. The EIS show Rs 5.07 Ω - 38.89 Ω and Rct 10.07 Ω -
496.4 Ω. The GCD show specific capacity 2118 mAh/g - 3416 mAh/g. | en_US |
