اثر مقدار تترا اتیل ارتو سیلیکات (TEOS) بر اندازه کره‌ها و ایجاد رنگ در اپال مصنوعی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه شهید بهشتی دانشکده علوم زمین

2 دانشگاه علم صنعت

10.22128/ijcm.2025.2964.0

چکیده

نخستین مرحله تولید اپال‌ مصنوعی به‌عنوان گوهرسنگ‌ ساخت کره‌های سیلیسی از محلول تترا اتیل ارتو سیلیکات (TEOS) است. اثر مقدار این محلول بر اندازه و در نتیجه، بازی رنگ اُپال در این پژوهش بررسی شد. به این منظور، کلوئیدهای سازنده کره‌های سیلیسی از آبکافت مقادیر 5، 6 و 7 درصد TEOS در اتانول تهیه شدند. نتایج میکروسکوپ الکترونی روبشی (SEM) نشان داد که کره‌های سیلیسی در همه نمونه‌ها تشکیل شده­اند و توزیع یکنواخت‌ دارند. نمونه‌های با 7 درصد TEOS دارای کره‌هایی با اندازه 230–260 میکرون بودند که امکان پراش نور و ایجاد بازی رنگ را فراهم کردند. در مقابل، نمونه‌های با 5 و 6 درصدTEOS ، به دلیل اندازه کوچک‌تر کره‌ها (100–120 و 140–150 میکرون)، بدون بازی رنگ بودند. این پژوهش نشان داد که افزایش TEOS تا 7 درصد، مناسب‌ترین شرایط را برای تولید اُپال‌های مصنوعی با بازی رنگ فراهم می‌کند.

کلیدواژه‌ها


عنوان مقاله [English]

The Effect of Tetraethyl Orthosilicate (TEOS) Content on Sphere Dimensions and Color Formation in Synthetic Opal

نویسندگان [English]

  • Fariborz Masoudi 1
  • ziba delpasand 1
  • Alireza Mirhabibi 2
1 shahid beheshti university
2 Iran University of Science and Technology (IUST)
چکیده [English]

The first step in producing synthetic opals as gemstones is the formation of silica spheres from a solution of tetraethyl orthosilicate (TEOS). This study investigated the effect of TEOS concentration on the size of the spheres and, consequently, on the play-of-color in the opals. For this purpose, colloids forming the silica spheres were prepared by hydrolyzing 5%, 6%, and 7% TEOS in ethanol. Scanning electron microscopy (SEM) results showed that silica spheres were formed in all samples with uniform distribution. The samples containing 7% TEOS had spheres with diameters of 230–260 microns, enabling light diffraction and the appearance of play-of-color. In contrast, the 5% and 6% TEOS samples lacked play-of-color due to the smaller sphere sizes (100–120 and 140–150 microns, respectively). This research demonstrates that increasing the TEOS content to 7% provides the optimal conditions for producing synthetic opals with play-of-color.

کلیدواژه‌ها [English]

  • Opal
  • Gemstone
  • Tetraethyl Orthosilicate
  • Silica Spheres
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