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Front Cover: Well‐defined poly(p‐phenylene) (PPP) is successfully synthesized by Negishi catalyst‐transfer polycondensation (NCTP) using tBu4ZnLi2. The PPP samples possess molecular weight values in the range of 2100–22 000 and molar mass dispersity values in the range of 1.09–1.23. Additionally, block copolymers, PPP‐b‐poly(3‐hexylthiophene), are synthesized to confirm the feasibility of chain extension between the different monomers based on NCTP. Further details can be found in article number 1700155 by Y. Ochiai, E. Goto, and T. Higashihara*. [ABSTRACT FROM AUTHOR]

The precise synthesis of poly(thioester)s with diverse structures is still a significant challenge in the polymeric materials field. Herein, we report a novel approach to the synthesis of well-defined poly(thioester)s by the controlled alternating copolymerization of cyclic thioanhydrides and episulfides induced by simple organic ammonium salts. Both the cation and anion have strong effects on the copolymerization. [PPN]OAc ([PPN]=bis(triphenylphosphine)iminium) with a bulky cation was proven to be efficient in initiating this polymerization, yielding poly(thioester)s with a completely alternating structure, controlled molecular weight, and narrow polydispersity. The poly(thioester) obtained from succinic thioanhydride and propylene sulfide is a typical semicrystalline material, possessing a high refractive index of up to 1.78. Because it uses readily available monomers, this method is expected to open up a new route to poly(thioester)s with diverse structures and properties., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Shape- and size-controlled synthesis of micro/nanostructures is of fundamental importance in many applications of physics and chemistry. Wet chemical growth methods have achieved shape- and size-controlled synthesis of colloidal nanocrystals of various compositions. Compared with wet chemical methods, electrochemical deposition (ECD) yields micro/nanostructures affixed to a substrate, but the resulting structures are poorly controlled. Herein, the controllable electrochemical fabrication of well-defined silver-oxide clathrate micro/nanostructures is realized by intentionally manipulating the previously neglected electrocarving process during electrodeposition growth (MEDEG). Most importantly, the dominance of the electrocarving and the electrodeposition growth process can be immediately manipulated by varying the deposition voltage and/or the composition of the electrolyte. Unique delta-wing-, arrowhead-, and butterfly-like silver-oxide clathrate structures are created using the MEDEG method. MEDEG complements the capability of ECD for controllable synthesis of micro/nanostructures of various materials directly on a substrate. The study details the mechanisms that may enable MEDEG to become a competitive alternative to traditional wet chemical methods in the controllable synthesis of micro/nanostructures. This understanding of MEDEG should motivate applications in fields which demand well-defined micro/nanostructures affixed to a substrate., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Mesoporous organosilica materials with organo-bridged silsesquioxane and novel structures have attracted great attention due to combined or enhanced properties. Here, we achieved facile synthesis of uniform well-defined mesoporous organosilica nanobowls with ethane- or ethane&thioether-bridged silsesquioxane framework by one-pot reaction. The possible formation mechanism may be attributed to be a dynamic growth, dissolution and reassembly process, including a uniform coating of ethane-bridged organosilica on the surface of mesoporous silica nanoparticles (MSNs) or mesoporous organosilica nanoparticles (MONs), gradual dissolution of MSNs or MONs core for the collapse of hollow spheres, and regrowth and reassembly of a small portion of the dissolved species. The framework stability of MSNs can be regulated by adjusting the amount of introduction of thioether-bridged silsesquioxane in the framework from 0 to 100%, which determines the structures of finally obtained products (nanobowls or rough nanoparticle (NPs)). The interesting results shed light on fundamental mechanisms of growth and dissolution for design and synthesis of novel structured materials. The ethane&thioether-bridged nanobowls show good hemocompatibility and low cytotoxicity compared with ethane-bridged nanobowls and calcined MCM-41-typed MSNs. The unique nanobowl structure, worm-like mesochannels and silsesquioxane framework make it as potential candidates for nanobiomedical applications., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In the past decade, iron oxide nanoparticles (IONPs) have attracted more and more attention for their excellent physicochemical properties and promising biomedical applications. In this review, we summarize and highlight recent progress in the design, synthesis, biocompatibility evaluation and magnetic theranostic applications of IONPs, with a special focus on cancer treatment. Firstly, we provide an overview of the controlling synthesis strategies for fabricating zero-, one- and three-dimensional IONPs with different shapes, sizes and structures. Then, the in vitro and in vivo biocompatibility evaluation and biotranslocation of IONPs are discussed in relation to their chemo-physical properties including particle size, surface properties, shape and structure. Finally, we also highlight significant achievements in magnetic theranostic applications including magnetic resonance imaging (MRI), magnetic hyperthermia and targeted drug delivery. This review provides a background on the controlled synthesis, biocompatibility evaluation and applications of IONPs as cancer theranostic agents and an overview of the most up-to-date developments in this area., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Carbon dots (CDs) have tremendous potential applications in bioimaging, biomedicine, and optoelectronics. By far, it is still difficult to produce photoluminescence (PL) tunable CDs with high quantum yield (QY) across the entire visible spectrum and narrow the emission peak widths of CDs close to those of typical quantum dots. In this work, a series of CDs with tunable emission from 443 to 745 nm, quantum yield within 13-54%, and narrowed full width at half maximum (FWHM) from 108 to 55 nm, are obtained by only adjusting the reaction solvents in a one-pot solvothermal route. The distinct optical features of these CDs are based on their differences in the particle size, and the content of graphitic nitrogen and oxygen-containing functional groups, which can be modulated by controlling the dehydration and carbonization processes during solvothermal reactions. Blue, green, yellow, red, and even pure white light emitting films (Commission Internationale de L'Eclairage (CIE)= 0.33, 0.33, QY = 39%) are prepared by dispersing one or three kinds of CDs into polyvinyl alcohol with appropriate ratios. The near-infrared emissive CDs are excellent fluorescent probes for both in vitro and in vivo bioimaging because of their high QY in water, long-term stability, and low cytotoxicity., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An Ag I dimer capped with labile organometallic diphosphorus ligands [Cp 2 Mo 2 (CO) 4 (η 2 -P 2 )] (Cp=C 5 H 5 ) acts as a highly pre-organized molecular precursor to direct the construction of 1D or 2D, and 3D organometallic-organic hybrid coordination polymers upon reaction with ditopic pyridine-based linkers. The formation of the supramolecular aggregates can be controlled by the stoichiometry of the organic molecules, and the mechanism is supported by DFT calculations., (© 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Well-defined poly(2,5-dihexyloxyphenylene-1,4-diyl) (PPP) is successfully synthesized by the Negishi catalyst-transfer polycondensation (NCTP) using dilithium tetra(tert-butyl)zincate ( t Bu 4 ZnLi 2 ). The obtained PPP possesses the number-averaged molecular weight (M n ) values in the range of 2100-22 000 and the molar-mass dispersity (Ð M ) values in the range of 1.09-1.23. In addition, block copolymers containing PPP and poly(3-hexylthiophene) (P3HT) segments (PPP-b-P3HT) are synthesized to confirm the feasibility of chain extension between the different monomers based on NCTP., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Non-neutral layered crystals, another group of two-dimensional (2D) materials that lack a well-defined van der Waals (vdWs) gap, are those that form strong chemical bonds in-plane but display weak out-of-plane electrostatic interactions, exhibiting intriguing properties for the bulk counterpart. However, investigation of the properties of their atomically thin counterpart are very rare presumably due to the absence of efficient ways to achieve large-area high-quality 2D crystals. Here, high-mobility atomically thin Bi 2 O 2 Se, a typical non-neutral layered crystal without a standard vdWs gap, was synthesized via a facial chemical vapor deposition (CVD) method, showing excellent controllability for thickness, domain size, nucleation site, and crystal-phase evolution. Atomically thin, large single crystals of Bi 2 O 2 Se with lateral size up to ∼200 μm and thickness down to a bilayer were obtained. Moreover, optical and electrical properties of the CVD-grown 2D Bi 2 O 2 Se crystals were investigated, displaying a size-tunable band gap upon thinning and an ultrahigh Hall mobility of >20000 cm 2 V -1 s -1 at 2 K. Our results on the high-mobility 2D Bi 2 O 2 Se semiconductor may activate the synthesis and related fundamental research of other non-neutral 2D materials.

Nanohybrids composed of two or more components exhibit many distinct physicochemical properties and hold great promise for applications in optics, electronics, magnetics, new energy, environment protection, and biomedical engineering. Microfluidic systems exhibit many advantages due to their unique characteristics of narrow channels, variable length, controllable number of channels and multiple integrations. Particularly their spatial-temporarily splitting of the formation stages during nanomaterials formation along the microfluidic channels favors the online control of the reaction kinetic parameters and in situ tuning of the product properties. This Review is focused on the features of the current types of microfluidic devices in the synthesis of different types of nanohybrids based on the classification of the four main kinds of materials: metal, nonmetal inorganic, polymer and composites. Their morphologies, compositions and properties can be adjusted conveniently in these synthesis systems. Synthesis advantages of varieties of microfluidic devices for specific nanohybrids of defined surfaces and interfaces are presented according to their process and microstructure features of devices as compared with conventional methods. A summary is presented, and challenges are put forward for the future development of the microfluidic synthesis of nanohybrids for advanced applications., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Green synthesis of nanoparticles (NPs) is a major developing field. In this study, we utilised Whitania somnifera leaves as a green source to synthesise platinum (Pt) NPs. Synthesised Pt NPs resulted from controlled synthesis of 12nm spherical particles. The synthesised Pt NPs were subjected to anti-diabetic applications resulting in a significant decrease in plasma glucose levels after injecting the Pt NPs into streptozotocin-induced diabetic rats., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Size tunable cobalt hollow nanospheres with high catalytic activity for the ammonia borane (AB) hydrolysis have been synthesized by using the solvothermal method. The complexation between Co 2+ and ethylenediamine is observed to be critical for the formation of the cobalt hollow nanospherical structure. The morphology of the cobalt hollow nanospheres can be regulated by adjusting the original ethylenediamine/ethanol volume ratio, reaction time and temperature. Impressively, the magnetic property study reveals that the coercivity of the as-synthesized cobalt hollow nanospheres is much enhanced compared with that of bulk cobalt materials. Meanwhile, Co/Pt bimetal hollow nanospheres (CoPtHS) and graphene-cobalt hollow composite nanospheres (CoHS-rGO) have also been explored. In comparison with the cobalt hollow nanospheres, both the CoPtHS and CoHS-rGO show higher catalytic activities and better repeatability for the catalytic hydrogen generation from AB hydrolysis. Moreover, it is noted that these catalysts could be recycled by using the magnetic separation method., (Copyright © 2017 Science China Press. Published by Elsevier B.V. All rights reserved.)

Information tagging and processing are vital in information-intensive applications, e.g., telecommunication and high-throughput drug screening. Magnetic suspension array technology may offer intrinsic advantages to screening applications by enabling high distinguishability, the ease of code generation, and the feasibility of fast code readout, though the practical applicability of magnetic suspension array technology remains hampered by the lack of quality administration of encoded microcarriers. Here, a logic-controlled microfluidic system enabling controlled synthesis of magnetic suspension arrays in multiphase flow networks is realized. The smart and compact system offers a practical solution for the quality administration and screening of encoded magnetic microcarriers and addresses the universal need of process control for synthesis in microfluidic networks, i.e., on-demand creation of droplet templates for high information capacity. The demonstration of magnetic suspension array technology enabled by magnetic in-flow cytometry opens the avenue toward point-of-care multiplexed bead-based assays, clinical diagnostics, and drug discovery., (© 2016 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

High-quality organic and inorganic van der Waals (vdW) solids are realized using methylammonium lead halide (CH3 NH3 PbI3 ) as the organic part (organic perovskite) and 2D inorganic monolayers as counterparts. By stacking on various 2D monolayers, the vdW solids exhibit dramatically different light emissions. Futhermore, organic/h-BN vdW solid arrays are patterned for red-light emission., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A preliminary study of the growth of 0D, 1D, and 2D nanostructures of uranium oxides with feature sizes from several nanometers down to 1 nm are presented. Cerium is successfully doped into these oxides and its influence on the growth dynamics and electrochemical performance investigated., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Site-selective biomineralization of Au nanostructures in the interior channel of Tobacco Mosaic Virus (TMV) is achieved by mutating threonine 103 in TMV to cysteine (T103C-TMV) to introduce the strong coordination interaction between the arrayed sulfhydryl ligands and gold species. By finely tuning the reaction conditions, Au nanoparticle chains and Au nanorods are successfully and exclusively synthesized inside the T103C-TMV nanotubes., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, a novel type of nanomedical platform, the double-walled Au nanocage/SiO(2) nanorattle, is successfully fabricated by combining two "hollow-excavated strategies"--galvanic replacement and "surface-protected etching". The rational design of double-walled nanostructure based on gold nanocages (AuNCs) and hollow SiO(2) shells functionalized respectively with p-aminothiophenol (pATP) and Tat peptide simultaneously renders the nanoplatforms three functionalities: 1) the whole nanorattle serves as a high efficient drug carrier thanks to the structural characteristics of AuNC and SiO(2) shell with hollow interiors and porous walls; 2) the AuNC with large electromagnetic enhancement acts as a sensitive surface-enhanced Raman scattering (SERS) substrate to track the internalization process of the nanorattles by human MCF-7 breast cancer cells, as well as an efficient photothermal transducer for localized hyperthermia cancer therapy due to the strong near-infrared absorption; 3) Tat-functionalized SiO(2) shell not only improves biocompatibility and cell uptake efficiency resulting in enhanced anticancer efficacy but also prevents the AuNCs from aggregation and provides the stability of AuNCs so that the SERS signals can be used for cell tracking in high fidelity. The reported chemistry and the designed nanostructures should inspire more interesting nanostructures and applications., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)