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Highly uniform silver orthophosphate microcrystals with novel tetrapod morphology are, for the first time, synthesized via a simple hydrothermal route with the assistance of urea. The effect of active crystal facets on the photocatalytic activity is principally investigated. The silver orthophosphate tetrapods exhibit significantly higher visible light activity than the polyhedrons for the degradation of toxic organic compounds due to the highly exposed {110} facets.Morphology control of photocatalysts has been considered to be one of the most promising avenues to improve their photocatalytic properties. [1][2][3][4][5] For example, various TiO 2 nanostructures including nanotubes, 3 nanosheets, 4 and nanorods 5 have been designed and synthesized, all of which exhibit higher activity than P25. However, its relatively wide band gap limits the photocatalytic applications under visible light irradiation. Therefore, it is desirable and compulsory to explore efficient visible-light-driven photocatalysts. Recently, silver orthophosphate (Ag 3 PO 4 ) has been demonstrated to be an active photocatalyst for the degradation of organic pollutants and the oxidation of water under visible light. 6,7 Specifically, Ag 3 PO 4 photocatalysts are reported to achieve a quantum efficiency up to 90% at wavelengths longer than 420 nm. 8 The research of Ag 3 PO 4 is thus attracting considerable interest. Up to now, many efforts have been devoted to further improving and optimizing their photoelectric and photocatalytic properties by means of semiconductor coupling 8,10-12 and polymer composites. 13 However, most of the as-mentioned researches mainly focus on the modification of Ag 3 PO 4 . It is well known that the morphology of materials is closely related to the exposed facets of the crystals, which directly affect the properties of the catalysts. 4b,c In this aspect, Ye and co-workers have succeeded in

The transformation of olefin to aromatics over ZSM-5 catalysts with different K-loadings has been investigated both in a continuous flow fixed-bed reactor and in a pulse microreactor. Investigation of variation of olefin aromatization activity with K-loadings shows that strong acid sites are indispensable for the converting of olefin to aromatics. As intermediates of olefin aromatization process, butadiene and cyclopentene not only show much higher aromatization activity than mono-olefins, but also can be transformed into aromatics over relatively weak acid sites of K/ZSM-5. A proposal is put forward, stating that among all the steps experienced in olefins aromatization, the formation of diene or cycloolefin from mono-olefins through hydrogen transfer is the key step and can be catalyzed by strong acid sites.