Physical and chemical properties of nanomaterials depend not only on their composition but also on their structure, morphology, phase, shape, size, distribution, and spatial arrangement. [1] Architectural control of nanosized materials with well-defined shapes is significant for "bottom-up" approaches toward future nanodevices. Therefore, finding new ways to assemble nanoobjects into finite superstructures is an important task.
One-dimensional (1D) nanomaterials have attracted much attention because of their intriguing properties and potential applications. [2] The impact of aligned and arranged 1D nanomaterial patterns would be tremendous in many areas, from nanoscale electronics and optoelectronics to molecular sensing. [3] In recent years, various procedures including the logs-on-a-river or Langmuir-Blodgett technique [4] and microfluidic, [5] electrical, [6] nanoimprinting, [7] selforganization, [8] and electric-field-effect-based demultiplexing methods [9] have been developed to assemble 1D nanomaterials into ordered patterns. These thought-provoking works inspired us to explore a simple approach for the low-cost, large-scale, room-temperature, and controlled growth of wellarranged nanostructures at atmospheric pressure.
As a result of the special structures and fascinating selfassembling functions, a biomaterial-based templating technique for the synthesis and assembly of novel artificial nanostructures of crystalline inorganic materials has given a promising focus in the preparation of various nanostructures. [10] In particular, l-cysteine, a very important biomolecule with three functional groups (SH, NH 2 , COOH), has a strong tendency to coordinate with inorganic cations and metals, and has been exploited in the synthesis of quantum dots, [11] nanotubes, [12] 3D spherical nanostructures from nanorods, [13] and flowerlike patterns with nanorods. [14] Herein, we report the facile and shape-controlled synthesis of dandelion-like l-cysteine-Pb architectures assembled from well-aligned nanowires in a binary aqueous solution of l-cysteine and Pb(OAc) 2 at room temperature, and their evolution into spherical and various flowerlike PbS microstructures under conventional hydrothermal conditions.