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Modifiable one-dimensional materials are extremely desired in various applications, especially in room-temperature (RT) chemiresistive gas sensing. New one-dimensional (1D) CdS-based metal chalcogenide nanowires with a surface fully covered amino group (denoted as Cd-ATP) were prepared by the coordination self-assembly method. Featuring densely covered organic functional motifs, Cd-ATP is able to selectively recognize H2S through hydrogen bonding interaction between the amino group and H2S. Cd-ATP exhibits high sensitivity, an ultra-low limit-of-detection (116.49 ppt) and fast response/recovery among all reported room temperature H2S sensing non-composite materials. This work provides inspiration for the design and preparation of novel surface fully functionalized 1D materials for various chemical applications. [ABSTRACT FROM AUTHOR]

Organic small molecule semiconductor (OSMS) microporous crystals with strong π–π interactions are rare but have great potential in applications requiring both excellent mass and charge transport. To obtain such a microporous structure, effective molecule design and control over the packing of the OSMS are necessary but still challenging. Herein, we report three meso-tetrakis (4-carboxyphenyl) porphyrin (TCPP) based porous OSMS materials, 1, 2 and 3, whose porosity and π–π interactions among TCPPs were modulated by varying the H-bonding linkage nodes. The relationship among the hydrogen bonding structure, packing mode and sensing performances has been carefully studied. With the largest overlap between porphyrin rings and strongest face-to-face π–π interactions in the prepared compound, 1 showed the best performances. Moreover, it also represents the first RT NO2 chemiresistive sensing material that simultaneously achieved an experimental limit of detection as low as 20 ppb and a time of recovery as short as 0.6 min. This work revealed the key role of H-bonding linkage node in constructing a microporous OSMS and provides a new type of high-performance rt chemiresistive gas sensing material. [ABSTRACT FROM AUTHOR]

A new series of 2D catalytic materials whose inorganic surfaces are fully covered with pre-designed "promoter" groups are reported. One of them showed excellent biomimetic catalytic activity and provided the lowest detection limit to glucose among the reported 2D materials and their composite materials. [ABSTRACT FROM AUTHOR]

The important application of metal oxides (MOs) as a chemiresistive sensing material can be severely hampered by their poor selectivity towards analyte molecules that possess a similar sensing activity. In this work, a new metal oxide@metal–organic framework (MO@MOF) core–sheath nanowire array material was prepared. Using a post-synthetic modification of the pore size in the MOF sheath, the channel traffic of the analyte molecules with a similar sensing activity but different kinetic diameter was successfully modulated, which profoundly enhanced the selectivity of the MOs. As a result, the materials obtained showed the highest selective response to acetone in the presence of benzene in all the reported materials. [ABSTRACT FROM AUTHOR]

Crystalline materials possessing both porous and conductive properties would create a great opportunity for novel electrical applications in fuel cells, batteries and sensors. However, these kinds of materials are rarely reported. Here, we report a new type of conducting porous crystalline material constructed by long distance Coulomb interactions among inorganic and organic components. The compound in this work shows a microporous structure, typical semiconductive properties, selective adsorption and an interesting electrical response to methanol and ethanol. [ABSTRACT FROM AUTHOR]

Electrically bistable materials have important applications in memory, displays, switches, sensors, and quantum computation. This communication reports a metal–organic framework (MOF) material as a new type of electrically bistable material. Taking advantage of the flexible structure of MOF materials, the electrically bistable states of the MOF were reversibly modulated between its crystalline and amorphous phases. Interestingly, the material's amorphous phase exhibited anomalously higher conductivity than the crystalline phase. Our results illustrated a convenient method to develop electrically bistable materials from MOFs. [ABSTRACT FROM AUTHOR]

A room-temperature solution phase reaction was developed to synthesize a covalent organic framework (COF) for the first time. The synthesized azodioxy-linked porphyrin-based COF (POR-COF) possesses a 2D chess board-like structure in the ab-plane and a 1D channel with an open-window size of around 1.9 nm along the c-axis in the modeled crystal structure. The electrical conductivity of POR-COF increases by more than 3 orders of magnitude through I2 doping. The photoconductivity of the I2-doped COF material was also studied firstly. POR-COF shows interesting doping-enhanced photo-current generation. [ABSTRACT FROM AUTHOR]

Two new isostructural coordination compounds exhibit the rare difunctional properties of both electron-transfer (ET) photochromism and ET thermochromism, which are significantly affected by halogen atoms. The thermocrystallographic studies of the same single crystal have elucidated the electron-donating nature of the halogen atoms. [ABSTRACT FROM AUTHOR]

We investigate the impact of different derivatives of 1,4-diazabicyclo[2.2.2]octane on the crystal structures of iodoplumbates by systematically increasing the size of the same organic amine, and present two new 1-D iodoplumbates. Optical studies reveal the semiconductor characteristics of all as-synthesized iodoplumbate hybrids. [ABSTRACT FROM AUTHOR]

A new bifunctional tetrazolate-5-carboxylate ligand has been prepared and employed in assembling 2-D Eu(iii)–Zn(ii) and Tb(iii)–Zn(ii) isostructural heterometallic MOFs with a (3,6)-connected kgd topology. The ligand in Tb3+ MOFs not only shows an antenna effect to transfer absorbed energy to Tb3+ centers to emit characteristic luminescence but also maintains good blue luminescent properties. Further, we have realized a rational design strategy to construct a series of Eu3+-doped Tb3+ MOFs emitting tunable three primary colors (RGB: red–green–blue) towards white light with high color rendering index and favorable correlated color temperature. [ABSTRACT FROM AUTHOR]

Mid-far infrared (IR) non-linear optical (NLO) materials are of great importance in military and civil fields. However, commercial IR-NLO crystals (such as AgGaS 2 , AgGaSe 2 and ZnGeP 2 ) do not currently satisfy the requirements of large second-harmonic generation (SHG) and high laser induced damage thresholds (LIDTs), which seriously limits their practical applications. Herein, we have developed a new series of salt-inclusion chalcogenides, [A 3 X][Ga 3 PS 8 ] (A = K, Rb; X = Cl, Br), which are constructed from alternate stacking of adamantane-like [Ga 3 PS 10 ] 6- cluster layers and cationic [A 3 X] 2+ salt layers. Importantly, they display both large SHG responses of several-fold and high LIDTs for dozens of times that of commercial AgGaS 2 , which exhibit the highest LIDTs among the reported IR-NLO materials with a larger SHG conversion efficiency than that of AgGaS 2 . These properties together with wide transparent region, type I phase-matching features and congruent-melting behaviors indicate they are promising IR-NLO materials.

A series of rare-earth zirconium chalcogenides Ln(2)ZrQ(5) (Ln = La, Sm, Gd; Q = S, Se) synthesized by using boron as the reducing reagent show unprecedented single-crystal's intrinsic voltage-dependent effects and order antiferromagnetically.