Abstract Rutile-type solid solutions; Ni1−xCoxTi(Nb1−yTay)2O8 (0 ≤ x ≤ 1, 0 ≤ y ≤ 1) were prepared by high temperature solid state reaction. The solid solutions of noibates (y = 0) had a rutile-type structure and those of tantalates (y = 1.0) had a trirutile-type one. The trirutile-type structure appeared in the composition of y ≥ 0.4. The crystal structures of these solid solutions for niobates and tantalates were refined by using synchrotron X-ray powder diffraction data and the R-factors were Rwp = 1.76–1.92% and Rp = 1.13–1.19% for niobates and Rwp = 10.3–12.2% and Rp = 6.78–9.14% for tantalates. Their lattice parameters for noibates ranges from a = 4.69413(2) to 4.70411(2) Å and c = 3.02187(1) to 3.03242(1) Å and those for tantalates ranges from a = 4.6946(2) to 4.7065(2) Å and c = 9.0829(3) to 9.1164(4) Å. The optical band gap for these solid solutions ranged from 1.63 to 2.50 eV and only NiTiTa2O8 exhibited photocatalytic activity for phenol decomposition under UV light irradiation. The dielectric constants for four end members, NiTiNb2O8, CoTiNb2O8, NiTiTa2O8 and CoTiTa2O8 were 25–75 in the temperature range from room temperature to 300 °C.

中文翻译：

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金红石型固溶体Ni 1−x Co x Ti(Nb 1−y Ta y ) 2 O 8 (0 ≤ x ≤ 1, 0 ≤ y ≤ 1)的合成及其光学性质

摘要金红石型固溶体；Ni1−xCoxTi(Nb1−yTay)2O8 (0 ≤ x ≤ 1, 0 ≤ y ≤ 1) 通过高温固相反应制备。noibates (y = 0) 的固溶体具有金红石型结构，而钽酸盐 (y = 1.0) 的固溶体具有三金红石型结构。y ≥ 0.4 的组成中出现了三聚体型结构。这些铌酸盐和钽酸盐固溶体的晶体结构通过使用同步加速器 X 射线粉末衍射数据进行细化，R 因子为 Rwp = 1.76–1.92% 和 Rp = 1.13–1.19% 铌酸盐和 Rwp = 10.3–12.2%钽酸盐的 Rp = 6.78–9.14%。它们的 noibates 晶格参数范围从 a = 4.69413(2) 到 4.70411(2) Å 和 c = 3.02187(1) 到 3.03242(1) Å，而钽酸盐的晶格参数范围从 a = 4.6946(2) 到 4.7065(2) Å c = 9.0829(3) 到 9.1164(4) Å。这些固溶体的光学带隙范围为 1.63 到 2.50 eV，只有 NiTiTa2O8 在紫外光照射下表现出对苯酚分解的光催化活性。在室温至 300 °C 的温度范围内，四个端部构件 NiTiNb2O8、CoTiNb2O8、NiTiTa2O8 和 CoTiTa2O8 的介电常数为 25-75。