Abstract
Single crystals of Fe1-xCoxTe0.85 have been synthesized successfully with x = 0, 0.02, 0.03, 0.05 and 0.10. The cobalt can be substituted for the iron site as Fe1-xCoxTe0.85 up to a solubility limit of x = 0.10, above which an impurity phase was observed. We obtained the intrinsic susceptibilities of these samples by Honda-Owen plot. The antiferromagnetic transition temperature decreases from about 70 K (x = 0) to 34 K (x = 0.05) with increasing the Co substitution level. Superconductivity was not discovered in this series, but a spin-glass like behavior was observed in 5 % substituted sample.