A new method for the passivation of the surface of infrared photodiodes operating at room temperature, spectral range 1.5-5.0 μm, by a mixture of higher fullerenes (h-f-mix) C₇₆ + C₇₈ + C₈₄ + C₉0 + ⋯ was suggested. The main service characteristics of photodiodes were studied. The passivation of photodiodes decreased their dark current by 14%. The Peltier effect was observed for the A³B ⁵ semiconductor/h-f-mix heterojunction.