The ammonium vanadium oxide cross-like nanobelt arrays with bamboo mat center were synthesized via hydrothermal method using NH4VO3 as precursors in presence of sodium carboxymethyl cellulose (CMC) at 160 degrees C for 6 h. Synthesized-products were characterized by XRD, FE-SEM, TEM, SA-ED, HR-TEM, and FT-IR. The effects of CMC concentration, pH value and temperature on the product morphology were investigated. pH value plays a crucial role in the formation of cross-like nanobelt arrays. Based on the results of time dependent experiments, the growth process of the cross-like NH4V4O10 nanobelt arrays is proposed. Furthermore, the mixed valance state vanadium oxide nanobelt arrays were obtained by calcination of the cross-like NH4V4O10 nanobelt arrays at 400 degrees C for 40 min and its capability of catalytic degradation of rhodamine B with oxygen in aqueous under UV/vis light irradiation was studied and compared with anionic dyes. The influence of temperature on the photocatalytic degradation was also investigated. The result showed that the degradation efficiency of rhodamine B catalyzed by the calcinated product was about 95% at pH 6.8 and 75 degrees C for 3 h and 30 min, suggesting it is a candidate of efficient catalysts for the photocatalytic degradation of rhodamine B under visible light irradiation. (C) 2012 Elsevier B.V. All rights reserved.