Tuning the density of ZnO nanorods and the field emission performance by seed layer in low temperature solution growth

In this work, the low temperature solution method was used to synthesize the ZnO nanorods. Its density can by tuned by simple adjusting the thickness of the seed layer. ZnO seed layers with stepwise increasing thickness were first deposited on the Si substrate by direct current sputtering. Field emission properties of the ZnO nanorods with different density were systematically measured and compared. The corresponding Fowler-Norheim (FN) plots are also given as inset, which shows the linear behavior to all four samples, demonstrated that the current was generated by field electron emission.