3D nanostructures have attracted much attention because of their unique properties and potential applications. [1][2][3][4][5][6][7][8][9][10][11][12][13] The simplest synthetic route to 3D nanostructures is probably selfassembly, in which ordered aggregates are formed in a spontaneous process.[2] However, it is still a big challenge to develop simple and reliable synthetic methods for hierarchically selfassembled architectures with designed chemical components and controlled morphologies, which strongly affect the properties of nanomaterials. Iron oxides have been extensively studied in diverse fields including catalysis, [14][15][16] environment protection, [17][18][19][20][21][22][23] sensors, [24] magnetic storage media, [25] and clinical diagnosis and treatment. [26] Various iron oxide structures, such as nanocrystals, [27][28][29] particles, [30,31] cubes, [32] spindles, [33] rods, [34,35] wires, [36] tubes, [37] and flakes, [38] have been successfully fabricated by a variety of methods. However, the self-assembly of these low-dimensional building blocks into complex 3D ordered nanostructures is still considerably more difficult. In order to further understand the mechanism of self-organization and expand the applications of iron oxide nanomaterials, self-assembled iron oxide 3D nanostructures need to be explored in more detail. Herein, we report the synthesis of novel 3D flowerlike iron oxide nanostructures by an ethylene glycol (EG)-mediated self-assembly process. Such a method has been adopted previously for the preparation of V 2 O 5 hollow microspheres, [7] SnO 2 nanowires, [39,40] and cobalt alkoxide disk-shaped particles.[41] However, in these previous studies, expensive metal organic compounds including acetates, oxalates, or acetylacetonates were used as metal-ion sources; in this study we used ferric chloride, an inexpensive and nontoxic reagent, as our iron source. By calcination at an elevated temperature, the assynthesized iron oxide precursor was transformed into iron oxide. The phase of the final product could easily be controlled to be either a-Fe 2 O 3 , c-Fe 2 O 3 , or Fe 3 O 4 , three of the most common iron oxides, simply by altering the calcination conditions. All of the products maintained their original flowerlike morphology. The reaction mechanism leading to the iron oxide precursor and the self-assembly process are discussed. As an example of potential applications, the as-obtained iron oxide nanomaterials were used as adsorbent in waste-water treatment, and showed an excellent ability to remove various water pollutants. In a typical procedure, ferric chloride (FeCl 3 ·6 H 2 O), urea, and tetrabutylammonium bromide (TBAB) were dissolved in EG. The solution was refluxed at ca. 195°C for 30 min. After cooling, the as-synthesized iron oxide precursor was collected as a green precipitate by four centrifugation and ethanolwashing cycles. The morphology of the precursor was studied by scanning electron microscopy (SEM). Figure 1a shows the SEM image of a typical sample composed of many un...

Although considerable progress has been made in carbon dioxide (CO) hydrogenation to various C chemicals, it is still a great challenge to synthesize value-added products with two or more carbons, such as gasoline, directly from CO because of the extreme inertness of CO and a high C-C coupling barrier. Here we present a bifunctional catalyst composed of reducible indium oxides (InO) and zeolites that yields a high selectivity to gasoline-range hydrocarbons (78.6%) with a very low methane selectivity (1%). The oxygen vacancies on the InO surfaces activate CO and hydrogen to form methanol, and C-C coupling subsequently occurs inside zeolite pores to produce gasoline-range hydrocarbons with a high octane number. The proximity of these two components plays a crucial role in suppressing the undesired reverse water gas shift reaction and giving a high selectivity for gasoline-range hydrocarbons. Moreover, the pellet catalyst exhibits a much better performance during an industry-relevant test, which suggests promising prospects for industrial applications.