ɹˈoʊdiəm ˈɑːksaɪd fˈɪlmz bᵻhˈeɪv æz ɐ fˈæst tˈuːkˈʌlɚɹ ɪlˌɛktɹoʊkɹˈoʊmɪk sˈɪstəm: ɹᵻvˈɜːsᵻbəl jˈɛloʊ lˈɛft ɹˈaɪt ˈæɹoʊ dˈɑːɹk ɡɹˈiːn ɔːɹ jˈɛloʊ lˈɛft ɹˈaɪt ˈæɹoʊ bɹˈaʊnpˈɜːpəl kˈʌlɚ tʃˈeɪndʒᵻz ɑːɹ əbtˈeɪnd ɪn kˌeɪˌoʊˈeɪtʃ səlˈuːʃənz baɪ ɐplˈaɪɪŋ vˈoʊltɪdʒ tˈɪldə wˈʌn vˈiː.
Rhodium oxide films behave as a fast two-color electrochromic system: Reversible yellow ↔ dark green or yellow ↔ brown-purple color changes are obtained in KOH solutions by applying voltage ~1 V.