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Self‐assembly of inorganic nanoparticles (NPs) is an essential tool for constructing structured materials with a wide range of applications. However, achieving ordered assembly structures with externally programmable properties in binary NP systems remains challenging. In this work, we assemble binary inorganic NPs into hierarchically pH‐responsive alternating copolymer‐like nanostructures in an aqueous medium by engineering the interparticle electrostatic interactions. The polymer‐grafted NPs bearing opposite charges are viewed as nanoscale monomers ("nanomers"), and copolymerized into alternating nano‐copolymers (ANCPs) driven by the formation of interparticle "bonds" between nanomers. The resulting ANCPs exhibit reversibly responsive "bond" length (i.e. the distance between nanomers) in response to the variation of pH in a range of ~7–10, allowing precise control over the surface plasmon resonance of ANCPs. Moreover, specific interparticle "bonds" can break up at pH≥11, leading to the dis‐assembly of ANCPs into molecule‐like dimers and trimers. These dimeric and trimeric structures can reassemble to form ANCPs owing to the resuming of interparticle "bonds", when the pH value of the solution changes from 11 to 7. The hierarchically responsive nanostructures may find applications in such as biosensing, optical waveguide, and electronic devices. [ABSTRACT FROM AUTHOR]

Colloidal molecules (CMs) are precisely defined assemblies of nanoparticles (NPs) that mimic the structure of real molecules, but externally programming the precise self‐assembly of CMs is still challenging. In this work, we show that the photo‐induced self‐assembly of complementary copolymer‐capped binary NPs can be precisely controlled to form clustered ABx or linear (AB)y CMs at high yield (x is the coordination number of NP‐Bs, and y is the repeating unit number of AB clusters). Under UV light irradiation, photolabile p‐methoxyphenacyl groups of copolymers on NP‐A*s are converted to carboxyl groups (NP‐A), which react with tertiary amines of copolymers on NP‐B to trigger the directional NP bonding. The x value of ABx can be precisely controlled between 1 and 3 by varying the irradiation duration and hence the amount of carboxyl groups generated on NP‐As. Moreover, when NP‐A* and NP‐B are irradiated after mixing, the assembly process generates AB clusters or linear (AB)y structures with alternating sequence of the binary NPs. This assembly approach offers a simple yet non‐invasive way to externally regulate the formation of various CMs on demand without the need of redesigning the surface chemistry of NPs for use in drug delivery, diagnostics, optoelectronics, and plasmonic devices. [ABSTRACT FROM AUTHOR]

Herein we describe the self‐assembly of an achiral molecule into macroscopic helicity as well as the emergent chiral‐selective spin‐filtering effect. It was found that a benzene‐1,3,5‐tricarboxamide (BTA) motif with an aminopyridine group in each arm could coordinate with AgI and self‐assemble into nanospheres. Upon sonication, symmetry breaking occurred and the nanospheres transferred into helical nanofibers with strong CD signals. Although the sign of the CD signals appeared randomly, it could be controlled by using the as‐made chiral assemblies as a seed. Furthermore, it was found that the charge transport of the helical nanofibers was highly selective with a spin‐polarization transport of up to 45 %, although the chiral nanofibers are composed exclusively from achiral building blocks. This work demonstrates symmetry breaking under sonication and the chiral‐selective spin‐filtering effect. [ABSTRACT FROM AUTHOR]

Among the enticing issues of chiral origins are: how chirality is born from the initial achiral units and the mechanisms for the transfer of chiral information. In this work, by combining a physical vortex and chiral seeds, a general process is revealed to generate chiral supramolecular polymers from achiral C3‐symmetric molecules. The symmetry‐broken assemblies from the achiral molecules could work as chiral seeds to initiate the polymerization of either homologous or heterologous achiral monomers. Concomitantly, the fragmentation of the polymer caused by the vortex during the nucleation‐elongation stages is shown to enlarge the domains of the chiral nuclei and then guide the polymer to grow into the predominant helicity with a high reactivity ratio. Moreover, the chiral structural information can be stored in different forms of assemblies. These new polymerization modes will provide guidance for the preparation of chiral materials. [ABSTRACT FROM AUTHOR]

In an article published in Angewandte Chemie, researchers Zhihong Nie, Yutao Sang, and their team discuss the UV light-induced generation of colloidal molecules with controlled structures. They use photolabile copolymer ligands to control the self-assembly of complementary copolymer-capped binary nanoparticles, resulting in clustered ABx or linear (AB)y structures. This research provides insights into the potential applications of photo-induced polymers in the field of nanotechnology. [Extracted from the article]

Zhihong Nie, Yutao Sang, and their colleagues have published a research article in Angewandte Chemie International Edition on the photo-induced self-assembly of copolymer-capped nanoparticles into colloidal molecules. They use photolabile copolymer ligands to control the self-assembly of binary nanoparticles A and B into clustered ABx or linear (AB)y structures. This research demonstrates the ability to generate colloidal molecules with precise structures using UV light. [Extracted from the article]

By constructing a supramolecular light‐harvesting chiral nanotube in the aqueous phase, we demonstrate a cooperative energy and chirality transfer. It was found that a cyanostilbene‐appended glutamate compound (CG) self‐assembled into helical nanotubes exhibiting both supramolecular chirality and circularly polarized luminescence (CPL). When two achiral acceptors, ThT and AO, with different energy bands were co‐assembled with the nanotube, the CG nanotube could transfer its chirality to both of the acceptors. The excitation energy could be transferred to ThT but only be sequentially transferred to AO. During this process, the CPL ascribed to the acceptor could be sequentially amplified. This work provides a new insight into the understanding the cooperative chirality and energy transfer in a chiral supramolecular system, which is similar to the natural light‐harvesting antennas. [ABSTRACT FROM AUTHOR]