Ferroelectric hysteresis loops were measured and the temperature evolution of the coercive field traced in [110]-oriented 0.8Pb(Mb_1/3Nb_2/3)O₃–0.2PbTiO₃ single crystal in the temperature range from 120 to 300 K at frequencies from 2 to 50 Hz. It was found that the coercive field rised with decreasing temperature in power-law manner at all frequencies. Temperature-dependent hysteresis model was used for approximation of acquired coercive field-temperature dependences. It was shown that nanoscale ferroelectric domains could be created at PMN-20PT surface by voltage pulses applied between the tip of atomic force microscope and bottom electrode at temperatures as low as 100 K.