Why is it that after annealing, while the size of the particles has become smaller and the crystallinity has decreased with XRD, and the electrical conductivity has decreased, but the band gap has also decreased? Is such a thing possible or is there an error in the experiments and calculations?
Dear Milad Fallah,
As you already know physical parameters after annealing depends on many factors. You're right that something is wrong with correlation of conductivity and band gap. Maybe you can tell more details about measurements techniques first.
Dear Dr. Shakirzyanov,
Thank you very much for your response. I searched this topic in articles. It seems that it can be related to Urbach energy. According to the Urbach energy, the electronic states of the defects can appear within the forbidden energy gap and lead to the reduction of the band gap while disrupting the quality of the crystal lattice. The decrease in crystal quality, particle size, and electrical conductivity of the samples after annealing (as mentioned above), together with the decrease in band gap can indicate an increase in Urbach energy resulted by defects due to receiving higher energy through annealing. So, according to Urbach energy, one of the most important reasons for the simultaneous reduction of band gap and crystal quality can be that the weaker bonds turn into the oxide states due to the annealing temperature.
Thank you very much for your cooperation and time.
Моддаларни қаттиқ ҳолатидан кўра суюқ ҳолатида тасвирлари яхшироқ кўриниш беришига қарайдиган бўлсак XRD даги тасвир тоблангандан кейин ўзгарган бўлиши мумкин. Бу жисмларнинг зичлигига боғлиқ
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