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Patchy nanoparticles (NPs) show many important applications, especially for constructing structurally complex colloidal materials, but existing synthetic strategies generate patchy NPs with limited types of symmetry. This article describes a versatile copolymer ligand‐based strategy for the scalable synthesis of uniform Au‐(SiO2)x patchy NPs (x is the patch number and 1 ≤ x ≤ 5) with unusual symmetry at high yield. The hydrolysis and condensation of tetraethyl orthosilicate on block‐random copolymer ligands induces the segregation of copolymers on gold NPs (AuNPs) and hence governs the structure and distribution of silica patches formed on the AuNPs. The resulting patchy NPs possess unique configurations where the silica patches are symmetrically arranged at one side of the core NP, resembling the geometry of polar small molecules. The number, size, and morphology of silica patches, as well as the spacing between the patches and the AuNP can be precisely tuned by tailoring copolymer architectures, grafting density of copolymers, and the size of AuNPs. Furthermore, it is demonstrated that the Au‐(SiO2)x patchy NPs can assemble into more complex superstructures through directional interaction between the exposed Au surfaces. This work offers new opportunities of designing next‐generation complex patchy NPs for applications in such as biomedicines, self‐assembly, and catalysis. [ABSTRACT FROM AUTHOR]

Ultrasmall silica‐based nanoparticles (SNPs) are attractive for application in many fields, but existing synthetic approaches show limited control over the size and morphology of these SNPs. This study describes a general single copolymer chain‐mediated strategy for the scalable synthesis of highly monodispersed symmetric and asymmetric SNPs with sub‐50 nm diameter. Random copolymers of poly(acrylic acid‐r‐styrene) intramolecularly collapse into ultrasmall single‐chain nanoparticles and serve as seeds to template the hydrolysis of silica precursors to produce uniform SNPs. It is shown in experiments and simulations that the composition and random architecture of the copolymers are crucial to the formation of ultrasmall seeds and the uniform deposition of silica. Furthermore, tailoring the architecture of copolymers can be used to produce ultrasmall asymmetric Janus‐like and dumbbell‐like SNPs with well‐defined polymer and silica domains. This study paves a new route to the scalable production of ultrasmall SNPs with tailored morphologies. [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]

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]

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]