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Searching for adaptable, versatile, and highly performing substances or building blocks is the goal of materials science. Owing to their exceptional structural modifiability, capability for supramolecular assembly, distinctive optoelectronic specialty, and superior device performance, various pyridazine-based (PD-based) heteroaromatic hydrocarbons (HAHs), which are embedded with the adjacent sp2-N pair (–N＝N–/＝N–N＝), have attracted increasing attention in the field of organic optoelectronic materials. In particular, organic field-effect transistors (OFETs), organic photovoltaic devices (OPVs), organic light-emitting diodes (OLEDs), fluorescence probes, luminescence, chromism, catalysis, and supramolecular assembly have witnessed notable advancements in recent years. This review categorized different molecular species, outlined structural traits, personality traits, and device performance and analyzed connections between those elements, including PD-based polymers, pure organic small molecules, pure organic complexes, and ligand–metal complexes as host materials, thermally active delayed fluorescence materials, electrode materials, chromism materials, fluorescence probes, organic catalysts, and energy materials. The aza-quantity, substituent, regioisomerism, dihydrogen bond, and dual-coordination effect were all summarized and expanded. In addition, the trends, challenges, and future aspects of PD-based HAHs were discussed and prospected. [ABSTRACT FROM AUTHOR]

Hard carbons (HCs) have great potential as anode material for high‐performance potassium ion batteries (PIBs). However, due to the complexity of HCs, the relationship between their structures and potassium (K) storage behaviors is still not quite clear. Here, three types of HCs with different structures are designed for further understanding the electrochemical storage processes. Among them, the carbon spheres (CS) exhibit impressive rate performance (161.6 mAh g−1 at 2 A g−1) and cycle stability (140.2 mAh g−1 at 2 A g−1 after 500 cycles). The superior performance of CS can be mainly ascribed to the intercalation into its locally‐ordered carbon nanocrystallites, and the charge/discharge processes are further characterized with significant pseudocapacitive dominating. Suitable nanocrystalline size and the ratio of defects with proper morphology are the key factors to improve K storage efficiency. This work will contribute to understanding the role of these factors in the K storage performance of carbon materials. [ABSTRACT FROM AUTHOR]

With the development of flexible devices, the demand for wearable power sources has increased and gradually become imperative. Zinc–air batteries (ZABs) have attracted lots of research interest due to their high theoretical energy density and excellent safety properties, which can meet the wearable energy supply requirements. Here, the flexibility of energy storage devices is discussed first, followed by the chemistries and development of flexible ZABs. The design of flexible electrodes, the properties of solid‐state electrolytes (SSEs), and the construction of deformable structures are discussed in depth. The researchers working on flexible energy storage devices will benefit from the work. [ABSTRACT FROM AUTHOR]

Shape‐selective catalysis plays a key role in chemical synthesis. Porous nanomaterials with uniform pore structures are ideal supports for metal nanoparticles (MNPs) to generate efficient shape‐selective catalysis. However, many commercial irregular porous nanomaterials face the challenge to realize satisfactory shape selectivity due to the lack of molecular sieving structures. Herein, we report a concept of creating shape selectivity in MNPs/porous nanomaterials through intentionally poisoning certain MNPs using suitable modifiers. The remaining MNPs within the substrates can cooperate with the channels to generate selectivity. Such a strategy not only applies to regular porous nanomaterials (such as MOFs, zeolites) but also extended to irregular porous nanomaterials (such as active carbon, P25). Potentially, the matching among different MNPs, corresponding modifiers, and porous nanomaterials makes our strategy promising in selective catalytic systems. [ABSTRACT FROM AUTHOR]

Despite many promising reports of plasmon-enhanced photocatalysis, the inability to identify the individual contributions from multiple enhancement mechanisms has delayed the development of general design rules for engineering efficient plasmonic photocatalysts. Herein, a plasmonic photocathode comprised of Au@SiO2 (core@shell) nanoparticles embedded within a Cu2O nanowire network is constructed to exclusively examine the contribution from one such mechanism: electromagnetic near-field enhancement. The influence of the local electromagnetic field intensity is correlated with the overall light-harvesting efficiency of the device through variation of the SiO2 shell thickness (5-22 nm) to systematically tailor the distance between the plasmonic Au nanoparticles and the Cu2O nanowires. A threefold increase in device photocurrent is achieved upon integrating the Au@SiO2 nanoparticles into the Cu2O nanowire network, further enabling a 40% reduction in semiconductor film thickness while maintaining photocathode performance. Photoelectrochemical results are further correlated with photoluminescence studies and optical simulations to confirm that the near-field enhancement is the sole mechanism responsible for increased light absorption in the plasmonic photocathode. [ABSTRACT FROM AUTHOR]

A multi-functional fluorescent probe based on PzDPM (10-ethyl-3,7-di(pyrimidin-4-yl)-10H-phenothiazine) for Hg2+, Cu2+ and ClO− has been synthesized and characterized. The probe comprises an electron-donating fluorophore core of 10-ethylphenothiazine and two Hg2+-specific chelating arms of pyrimidin-4-yl. The 10-ethylphenothiazine also acts as a Cu2+/ClO−-specific reactive moiety. PzDPM exhibits green fluorescence and selectively senses Hg2+/Cu2+ upon coordination/reaction in acetonitrile (MeCN), and behaves as a turn-off chemosensor or ratiometric chemodosimeter, respectively. On the other hand, PzDPM is very weakly emissive in aqueous solution but acts as an excellent turn-on chemodosimeter for ClO− in 1 : 4 (v/v) MeCN : Tris–HCl (10 mM, pH = 7.0) with a maximum fluorescent intensity increase of over 110-fold. The probe PzDPM allows the determination of Hg2+, Cu2+ and ClO− at 10−7 M levels with satisfactory selectivity. [ABSTRACT FROM AUTHOR]

Abstract: A novel fluorescent ratiometric chemosensor based on 4-pyren-1-yl-pyrimidine (PPM) has been designed and prepared for the detection of Hg2+ in the presence of other competing metal ions in acetonitrile. The photo exhibits fluorescence color change of PPM from blue to green without and with Hg2+, which red shift of wavelength about 105nm in fluorescence emission spectra. It can serve as a highly selective chemodosimeter for Hg2+ with ratiometric and naked-eye detection. The photophysical properties of PPM confirmed a 2:1 (PPM–Hg2+) binding model and the spectral response toward Hg2+ was proved to be reversible. [Copyright &y& Elsevier]

Abstract: A new neutral iridium (III) complex Ir(TBT)2(acac) based on 2-thiophen-2-yl-benzothiazole (TBTH) ligands has been synthesized and characterized. Ir(TBT)2(acac) exhibited color change from red to orange without and with Hg2+, at the same time has a blue shift about 23nm in fluorescent emission spectra. So it can serve as a highly selective chemodosimeter for Hg2+ with ratiometric and naked-eye detection. The sensor allowed determination of Hg2+ in the working range of 3μM–10μM with a detection limit of 2.14μM. The phosphorescent chemosensor exhibited excellent selectivity and sensitivity for Hg2+ detection. [Copyright &y& Elsevier]

Metal-organic frameworks (MOFs) with an ordered channel and porosity show great promise for a myriad of purposes. Unfortunately, the coordination bond of metal ions and organic ligands easily weakens in unfavorable environments, which poses a key problem in expanding the application of MOFs. Herein, we report a general and efficient strategy to enhance the stability and preserve the porosity of MOFs by coating them with reduced graphene oxide (rGO). The prepared hybrid material consisted of MOFs and rGO, as the core and the protective shell, respectively. It is worth noting that the obtained MOFs@rGO composite material maintained a well-defined crystal structure and showed good catalytic activity as well as enhanced stability. Notably, this novel and general method of coating MOFs with a thin protective rGO shell will broaden the application fields of MOFs and open up a new avenue for the research of MOFs., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)