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Hollow and mesoporous hierarchical microstructures have been found to be an attractive class of materials for their superior physical properties and potential applications.Different structures of ZnTe including nanoflowers,nanodots,nanorods,quasispheres and tetrahedrons nanocrystals have been synthesized using different synthetic techniques[1-3].In the present work,hydrothermal method has been used for the facile synthesis of hollow and mesoporous zinc telluride(ZnTe)hierarchical microspheres.Different reaction parameters have been used and the detailed growth mechanism has been proposed.These hollow and mesoporous microspheres are also used for the photoreduction of carbon dioxide(CO2)under visible-light irradiation(λ ≥ 420 nm),resulting in the production of methane(CH4)as the major product.The higher yield of methane in case of the microspheres may be attributed to the fact that these hollow and mesoporous microspheres,because of their special shape,low density,large fraction of voids and their ability to store comparatively larger amount of CO2 as compared to the nanocrystals,can adsorb an enormously large amount of CO2 for its efficient photoconversion into CH4.The higher yield of CH4 over these microspheres can also be attributed to the superior physical properties of the mesoporous materials.The comparatively lower yield of CH4 in case of nanocrystals is due to the agglomeration that reduces the active sites over these nanocrystals and results in lower yield of CH4.