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Neutral triple gauge couplings(nTGCs)are absent in the standard model effective theory up to dimension-6 operators,but could arise from dimension-8 effective operators.In this work,we study the pure gauge operators of dimension-8 that contribute to nTGCs and are independent of the dimension-8 operator involving the Higgs doublet.We show that the pure gauge operators generate both ZγZ* and Zγγ* vertices with rapid energy dependence ∝ E5,which can be probed sensitively via the reaction e+e-→ Zγ.We demonstrate that measuring the nTGCs via the reaction e+e-→ Zy followed by Z→ q(q)decays can probe the new physics scales of dimension-8 pure gauge operators up to the range(1-5)TeV at the CEPC,FCC-ee and ILC colliders with √s =(0.25-1)TeV,and up to the range(10-16)TeV at CLIC with √s =(3-5)TeV,assuming in each case an integrated luminosity of 5 ab-1.We compare these sensitivities with the corresponding probes of the dimension-8 nTGC operators involving Higgs doublets and the dimension-8 fermionic contact operators that contribute to the e+e-Zγ vertex.