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Non-stoichiometric cuprous oxide, Cu2O can be prepared in laboratory. In this oxide, copper to oxygen ratio is slightly less than 2:1. Can you account for the fact that this substance is a p-type semiconductor? |
Answer» Since Cu2O is non-stoichiometric oxide, it contains Cu in two oxidation states, +1 and +2. Cu2+ provides an excess of positive charge. As a result an electron from a neighboring Cu+ is transferred to Cu2+. The transfer of electron leaves behind a hole, which carries an extra positive charge and a negative hole is created. It appears that the positive hole moves through the lattice, hence it appears as P-type semiconductor. |
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