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Free‐standing zinc oxide in the forms of films and fibrous materials are expected to be used as functional devices such as piezoelectric devices and catalyst filters without being limited by the growth substrate. Herein, a synthetic morphology‐control method for 2D and 1D free‐standing ZnO materials with ordered and nanoporous structures by conversion of liquid‐crystalline (LC) zinc hydroxide carbonate (ZHC) nanoplates is reported. As a new colloidal liquid crystal, the LC ZHC nanoplate precursors are obtained by a biomineralization‐inspired method. The approach is to control the morphology and crystallographic orientation of ZHC crystals by using acidic macromolecules. Their nano‐scale and oriented structures are examined. The LC oriented ZHC nanoplates have led to the synthesis of free‐standing films and microfibers of ZHC in centimeter‐level lengths, with the successful thermal conversion into free‐standing films and microfibers of ZnO. The resultant ZnO films and ZnO microfibers have nanoporous structures and preferential crystallographic orientations that preserve the alignment of ZHC nanoplates before conversion. [ABSTRACT FROM AUTHOR]

We here report the development of new thermotropic colloidal liquid‐crystalline (LC) organic/inorganic hybrids consisting of a hydroxyapatite (HAp)/poly(acrylic acid) (PAA) nanorod and a dendritic forklike mesogen. Complexation of the HAp/PAA nanorod covered with negatively charged PAA and a cationic forklike mesogen through electrostatic interactions and cation metathesis results in the surface modification of the HAp/PAA nanorod with the forklike mesogen. While the HAp/PAA nanorod forms a lyotropic colloidal LC phase in the aqueous dispersion, the HAp/PAA nanorod modified with the forklike mesogen exhibits thermotropic colloidal LC phases in the solvent‐free states. The biomineral‐based organic/inorganic colloidal liquid crystals exhibiting thermotropic LC properties have potential for the development of new stimuli‐responsive sustainable materials. [ABSTRACT FROM AUTHOR]