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With the increase in demand of electronic devices in the modern civilization, research in material science is being projected to grow in faster rate. In this facet, coordination polymer (CP) based electronic device is one of the promising candidates to the material researchers. Herein, two new Zn(II) and Cd(II) based one‐dimensional (1D) CPs, denoted as [Zn(4‐avp)2(5‐nip)] ⋅ (solvent)x (1) and [Cd(4‐avp)(5‐nip)(CH3OH)] (2) have been synthesized using relatively less explored highly conjugated polycyclic aromatic hydrocarbon (PAH) based monodentate ligand, 4‐[2‐(9‐anthryl)vinyl]pyridine (4‐avp) and bidentate linker 5‐nitroisophthalic acid (H25‐nip). In this instance, the CP 1 creates 1D chain polymer, while CP 2 is made up with 1D ladder polymer. It is interesting to note that both the CPs exhibit semiconducting nature and generate metal‐semiconductor (MS) junction Schottky barrier diodes (SBDs). However, Cd‐based CP 2 shows higher charge transport as compared to Zn‐CP 1, which could be due to stronger π⋅⋅⋅π contacts as well as larger size of Cd metal in CP 2. The experimental results are well corroborated with theoretical density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

In this study, we report the synthetic method of two distinct supramolecular metallogels, namely Mn-BDA and Cd-BDA, using Mn(II) acetate tetrahydrate, Cd(II) acetate dihydrate and butane-1,4-dicarboxylic acid (BDA). DMF, a polar aprotic solvent, was immobilized in both metallogel-networks for their synthesis. The metallogelation of Mn-BDA was successfully attained through the instant mixing of a Mn(II)-source and BDA in DMF solvent media. By applying ultrasonication, a Cd-BDA metallogel was prepared. The stoichiometry of gel-forming components concerning metal salts and the LMWG are accountable to obtain respective stable metallogels. Rheological parameters such as storage modulus (G′) and loss modulus (G′′) explored the mechanical flexibility of the synthesized metallogels through amplitude and angular frequency sweep experiments. Both the metallogels possess significant mechanical stability, which was determined by monitoring diverse gel-to-sol transition shear strain values (γ%). Distinctive morphological visualizations of both of these metallogels (i.e., Mn-BDA and Cd-BDA) were made via field emission scanning electron microscopic (FESEM) studies, demonstrating a fibrous inter-connected network with a hierarchical self-assembled arrangement for Mn(II)-based metallogels and a typical stacked-flake-like association with hierarchical motifs for Cd(II)-based metallogels. EDAX elemental mapping substantiated the presence of metallogel-forming agents such as individual metal acetate salts, BDA acting as a low-molecular weight gelator, and gel-immobilized solvents such as DMF. Furthermore, Fourier transform infrared spectroscopy and ESI-mass spectroscopy were performed for both these supramolecular metallogels. FT-IR spectroscopic and ESI-mass spectroscopic results clearly substantiate the possible non-covalent supramolecular interactions among basic molecular repeating moieties, i.e., butane-1,4-dicarboxylic acid (the low-molecular weight gelator), individual metal salts and gel-immobilized polar aprotic solvent DMF for the construction of distinct stable supramolecular metallogel-systems. The semiconducting property of the fabricated metallogels was investigated. Two Schottky diodes (SDs) composed of ITO/Cd-BDA/Al and ITO/Mn-BDA/Al in a sandwich pattern with Al serving as the metal electrode were fabricated. Both these metallogel-based devices effectively offer significant semiconducting diode features with non-linear J–V characteristics. The non-ohmic conduction protocol of the fabricated metallogel-based devices was explored. Mn-BDA and Cd-BDA metallogel-based fabricated devices have rectification ratios of 6.67 and 23.50, respectively. The gel-based diode performances were examined by observing the voltage-dependent current density, charge transportation and rectification ratio. [ABSTRACT FROM AUTHOR]

A photoactive two-dimensional coordination polymer (2D CP) [Zn2(4-spy)2(bdc)2]n (1) [4-spy = 4-styrylpyridine and H2bdc = 1,4-benzendicarboxylic acid] undergoes a photochemical [2 + 2] cycloaddition reaction upon UV irradiation. Interestingly, the crystals of 1 show different photomechanical effects, such as jumping, swelling, and splitting, during UV irradiation. In addition, the CP was employed for conductivity measurements before and after UV irradiation via current density–voltage characteristics and impedance spectroscopy, which suggest that they are semiconducting in nature and can be used as Schottky diodes. Thus, this work demonstrates the potential dual applications of a 2D CP based on photosalient and conductivity properties. [ABSTRACT FROM AUTHOR]

Three mixed-valence trinuclear cobalt(III)–cobalt(II)–cobalt(III) complexes, [CoII{(μ-L1)(μ-OAc)CoIII(OAc)}2]·2.67H2O (1), [CoII{(μ-L1)(μ-OOCPh)CoIII(DMSO)0.8(OOCPh)0.2}2](ClO4)1.6 (2) and [CoII{(μ-L2)(μ-OOCPh)CoIII(DMSO)0.75(OOCPh)0.25}2](ClO4)1.5 (3), have been synthesized using two tetradentate N2O2 donor 'reduced Schiff base' ligands, H2L1 {1,3-bis(2-hydroxybenzylamino)2,2-dimethylpropane} and H2L2 {2,2′-[1,1′-(propane-2,2-diyldiimino)diethylidene]diphenol}, and acetate or benzoate as anionic co-ligands. These complexes have been characterized by spectroscopic measurements and their solid state structures have been determined by single crystal X-ray diffraction analysis. The cobalt(III)–cobalt(II)–cobalt(III) skeletons of complexes 1 and 2 are linear, centrosymmetric; but in complex 3, it is non-centrosymmetric. Both the central cobalt(II) and terminal cobalt(III) atoms are hexa-coordinated in all three complexes. The structure directing role of several noncovalent interactions in the solid state of the complexes has been investigated focusing on the H-bonding interactions mediated by the co-crystallized water molecules in 1 and the perchlorate counterions in 2 and 3. Thermo-gravimetric analysis (TGA) provided a thermal driven pathway to observe the loss of lattice water molecules from complex 1. All the complexes show good electrical conductivity, which has been rationalized by band gap measurements. The band gap in the solid state was determined experimentally and also by DFT calculations and it confirms that each of the complexes behaves as a semiconductor. These complexes have been used to fabricate Schottky barrier diodes. [ABSTRACT FROM AUTHOR]

Different aliphatic amine (including triethylamine (TEA), ethylenediamine (EN), N,N,N0, N0-tetramethylethylenediamine (TEMED), diethylenetriamine (DETA), triethylenetetramine (TETA)) directed Mg(II)-metallogels have been successfully achieved. Amines with single or multiple N-site(s) are utilized for the origination of stable Mg(II)-metallogels. Exhaustive rheological investigations establish the mechanical stability of the Mg(II)- metallogels. The thixotropic properties of the rheological experiments clarify the self-healing nature of different Mg(II)-metallogels. The morphological variations of different aliphatic-amine-directed metallogels are verified through scanning electronic microscopic images. The presence of metallogel-forming chemicals has been experimentally checked through elemental analyses. The electrical properties of the self-healable Mg(II)- metallogel-based systems have been explored. The I-V characteristics of different metallogels show a Schottky device nature for a gel-directed sandwich configuration with an ITO/metallogels/Al structure. The metallogelmediated fabricated metal-semiconductor junction devices show very prominent rectification ratios (on-off ratio). [ABSTRACT FROM AUTHOR]

A Cu(II)-based metal–organic framework (MOF) [Cu(muco)(3,5-DCP)]n (1) has been synthesized by using linear rigid aliphatic dicarboxylic acid, trans,trans-muconic acid (H2muco) and 3,5-dichloropyridine (3,5-DCP) as an auxiliary ligand. The MOF adopts a square-grid two-dimensional (2D) structure with paddle-wheel [Cu2(OOC)4] robust secondary building units (SBUs). The 3,5-DCP ligands are perpendicularly projected from the SBUs at both sides and undergo interdigitation via antiparallel π⋯π stacking interactions among 3,5-DCP ligands to fabricate three-dimensional (3D) supramolecular architecture. The π⋯π interactions favour the formation of Cl⋯Cl stacking contacts. These non-covalent interactions are further validated by density functional theory (DFT) calculation. In addition, the synthesized MOF is tested for conductivity measurements via current density–voltage characteristics, as well as impedance spectroscopy, which reveal that the MOF is semiconducting in nature and can be used as a Schottky diode. [ABSTRACT FROM AUTHOR]

A coordination polymer (1) and a trinuclear complex (2) have been synthesized using a compartmental N2O2O2′ donor Schiff base ligand. Both complexes are characterized using different spectroscopic techniques and their structures are determined using single crystal X-ray diffraction analyses. Energies associated with different non-covalent (S⋯O chalcogen bonds, C–H⋯H–C, C–H⋯I and C–H⋯π) interactions in the solid state of both complexes have been calculated using the Turbomole program. Investigations of electrical conductivity and photosensitivity of both complexes reveal that suitable Schottky diode devices could be fabricated from both complexes. The current vs. voltage plots of the complex based devices have been used to calculate the conductivity under dark and irradiation conditions. In both complexes the charge transportation mainly occurs through space which involves the hopping process. Standard band theory has been used to compare the experimental and theoretical results of optoelectronic measurements. The calculations confirm that both are direct band gap (2.78 and 3.30 eV) semiconductors and that complex 1 exhibits a lower band gap, in line with the experimental results (3.21 and 3.43 eV in 1 and 2, respectively). [ABSTRACT FROM AUTHOR]

The systematic understanding of structure‐property correlations of coordination compounds can be utilized for their potential applications. To rationalize this concept, a mixed ligand based Cu(II) compound [Cu2(nac)4(4‐nvp)2] (1) (Hnac=3‐(1‐naphthyl)acrylic acid and 4‐nvp=4‐(1‐naphthylvinyl)pyridine) has been synthesized and single crystal is obtained by the simple layering technique. Compound 1 has fascinating paddle wheel structure which undergoes weak C−H⋅⋅⋅π interactions to generate a three‐dimensional (3D) supramolecular aggregate. An electrical analysis, i. e. current‐voltage (I–V) measurement of this material, exhibited rectifying behavior in the forward bias, which affirms the formation of a Schottky diode. Impedance spectroscopy (IS) analysis has also been performed to get insight into the diode application. Besides, the fluorescence emission of 1 is quenched by 2,4,6‐trinitrophenol (TNP) and 2,4‐dinitrophenol (DNP), among other nitroaromatics, and the maximum quenching efficiency is observed for TNP (98 %). The limits of detection (LOD) are determined by following 3σ methods and are found to be 0.77 μM (TNP), and 0.85 μM (DNP). Interestingly, compound 1 also exhibits biomimetic catechol oxidase‐like activity for the oxidation of catechol to quinone. Therefore, the synthesized compound can be considered as a promising candidate for multi‐functional applications in material science. [ABSTRACT FROM AUTHOR]

Bovine Serum Albumin protein-based two fascinating functional self-healing Cu(II) metallohydrogel scaffolds (MD1 and MD2) have been studied for the development of metal-semiconductor junction based Schottky diode device. Multiple metal-semiconductor (MS) junction devices, offering the sandwich-like configuration of Indium tin oxide (ITO)/ metallogel/Aluminium (Al), have been made-up to investigate the electrical properties of the synthesized metallohydrogel materials. Optical characterizations including optical band gap measurement have been carried out using Tauc's equation for both the metallohydrogels. The current-voltage (I-V) characteristics of just made-up devices are studied under irradiation and non- irradiation conditions to explore the electrical features through investigating the charge transport phenomenon. The electrical conductivity gets estimated as 3.13 × 10−5 S.m−1 and 2.69 × 10−5 S.m−1 for MD1 and MD2 under dark condition, and 11.06 × 10−5 S.m−1 and 5.99 × 10−5 S.m−1 for MD1 and MD2, respectively, in photo-irradiation. The measured optical and electrical properties of MD1 and MD2 metallohydrogels are thoroughly investigated and the data indicates that MD1 and MD2 metallohyrogels are semiconducting in nature with excellent photo-responsive behaviour. Moreover, the representative I − V characteristic of the MD1 and MD2 metallohydrogels at both irradiation and non-irradiation conditions represents the nonlinear rectifying behaviour, a typical signature for Schottky diode (SD). • The metal-semiconductor junction based Schottky diode device has been executed by protein based metallohydrogels. • Optical characterizations including optical band gap measurement have been carried out using Tauc's equation. • I - V characteristics of just made-up devices are studied under irradiation and non-irradiation conditions. • Photo-responsive Schottky Barrier Diode type electronic devices with excellent charge transport property are explored. • I − V characteristic represents the nonlinear rectifying behaviour, a typical signature for Schottky diode (SD). [ABSTRACT FROM AUTHOR]

Herein, we have presented the crystal structure, supramolecular structure and band structure along with dielectric, electrical transport and optoelectronic properties of a [Mg(H2O)6]2+ templated 3D hydrogen bonded supramolecular framework (HSF) {[Co(2,5-Pdc)2,(H2O)2]2−·[Mg(H2O)6]2+·4(H2O)} (where 2,5-pdc = 2,5-pyridinedicarboxylate) synthesized by reflux method. The complex crystallizes in the P1¯ space group. The 3D network of the complex has been built up by hydrogen bonding interactions between 2D supramolecular sheets of the complex. The proton conductivity and activation energy of the complex are ∼10−4 S cm−1 at 40 °C and ∼0.3 eV, respectively, under vacuum. It exhibits anomalous dielectric behavior due to the gradual release of guest water molecules above 40 °C. The complex is a semiconductor with a band gap of 1.626 eV and is capable of absorbing electromagnetic radiation in the range of 355–730 nm. The ITO/complex/Al sandwiched device exhibits Schottky barrier diode (SBD)-like behaviour with a rectification ratio of 13 in the dark and 34 under visible light at 1 V. When exposed to visible light (AM 1.5G) the value of its conductivity enhances 1.35 times, compared to that in the dark. It has been shown that the complex is a semiconducting proton conducting photoresponsive HSF. [ABSTRACT FROM AUTHOR]

A new Cd(II)-based two-dimensional coordination polymer (2D CP) [{Cd2(cis-1,4-chdc)2(1,10-phen)2}·5H2O]n (1) has been synthesized at room temperature by a slow diffusion technique using a 1,4-cyclohexanedicarboxylic acid (1,4-H2chdc) and 1,10-phenanthroline (1,10-phen) mixed-ligand system. CP 1 was characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffraction (PXRD) analysis, single crystal X-ray diffraction (SCXRD) and thermogravimetric analysis (TGA) techniques. The structural analysis has revealed that CP 1 forms a 2D layer structure with guest water molecules encapsulated in the cavity generated by the Cd(II) centers and 1,4-chdc anions. Interestingly, CP 1 shows electrical conductivity in the semiconductor region and behaves as a Schottky barrier diode. In order to compare the conductivity with a similar type of CP made of another d10 metal ion Zn(II), a reported CP {Zn(cis-1,4-chdc)(1,10-phen)(H2O)}n (2) with a 1D helical structure was synthesized and its conductivity was compared. CP 2 also exhibits electrical conductivity and reveals Schottky barrier diode behavior. However, it has been found that CP 1 shows better properties for electronic device application as compared to CP 2. [ABSTRACT FROM AUTHOR]

A functionally advanced Ni(II)-metallogel (Ni-D-TA) was prepared through the sonication of nickel(II) chloride hexahydrate and 4,4′-dipyridyl and triethyl amine in an N,N-dimethyl formamide solvent at room temperature under ambient conditions. The rheological investigation proves the mechanical stability of the functional Ni-D-TA metallogel. FESEM microstructural analysis unveils a rock-like morphology with a self-assembled architecture of the Ni-D-TA metallogel. The optical and electrical properties of the metallogel were thoroughly examined, and the results indicate the semiconducting nature of Ni-D-TA. Electrical conductivity and photosensitivity show its capability in optoelectronic device application. Also, it is seen from the experimental studies that light irradiation endows the metallogel with better device parameters and charge transport properties. The rectification ratio increases to two-fold under illumination. This type of metallogel with photosensing Schottky behaviour advances the area of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Herein, we report the crystal structure, supramolecular structure, electronic transport properties and optoelectronic behaviour of a co-crystal made of tetrabromoterephthalic acid (TBTA) and quinoxaline (QUIN) (1 : 1). The sample has been characterized using thermogravimetric analysis and spectral techniques. Moreover, theoretical analyses of noncovalent interactions, optical properties and the band structure of the co-crystal have been performed. The co-crystal has been crystallized in an orthorhombic system with the Pnma space group and the constituent molecules assemble in the solid state by using O–H⋯N hydrogen bonding, π⋯π, Br⋯π and Br⋯O interactions. The ground state geometry optimization over the hydrogen bonded dimer by DFT method indicates that TBTA acts as the donor and QUIN as the acceptor within the self-assembled co-crystal. According to UV-vis spectroscopic study the bandgap of the co-crystal is ∼3.18 eV. In the solid state it exhibits a broad emission band with a maximum at 405 nm while in aqueous medium its photoluminescence emission peaks are obtained at 350 and 403 nm. The values of the average fluorescence lifetime of the sample in aqueous medium are 3.38 ns at 352 nm and 4.94 ns at 403 nm. Under UV-irradiation, the co-crystal emits violet-blue light. The emission spectrum in solution phase shows a relative quantum yield of 0.018. Band structure calculation indicates that the co-crystal is a p-type semiconductor with a bandgap of 2.835 eV. Due to its semiconducting character, the ITO/co-crystal/Al sandwiched structured device acts as a Schottky barrier diode with rectification ratio, ideality factor, barrier height and series resistance of 41, 1.36, 0.70 eV, and 26.97 kΩ, respectively. The current through the device increases substantially under visible light exposure. Upon visible light illumination the values of electrical conductivity, mobility and carrier concentration increase by 35 (±0.5), 54 (±0.5) and 6 (±0.5)%, respectively, with respect to dark conditions. It has been shown that π⋯π and hydrogen bonding interactions can play a crucial role in producing the donor–acceptor (D–A) type co-crystal, semiconducting behaviour can be incorporated in the organic co-crystal utilizing π⋯π and hydrogen bonding interactions and weak intermolecular π⋯π, Br⋯π and Br⋯O interactions can act as the pathway for electrical conduction. [ABSTRACT FROM AUTHOR]

Summary: Terephthalic acid‐based supramolecular metallogel of Cu(II) (ie, Cu‐TA) is developed by sonicating the mixture of copper(II) acetate monohydrate and terephthalic acid in N,N‐dimethyl formamide solvent. The rheological study is performed to expose the mechanical property of metallogel. The flake‐like morphological patterns are found through FESEM microstructural investigations. The formation strategy, crystalline nature, and thermal behavior of the Cu‐TA metallogel are also studied. The optical and electrical properties of Cu‐TA metallogel are exhaustively scrutinized, and the measured data show that Cu‐TA metallogel is semiconducting in nature. The electrical analysis indicates that the conductivity of Cu‐TA metallogel increased up to ~four times under illumination (7.49 × 10−5 S m−1) rather than the nonirradiation condition (1.83 × 10−5 S m−1). The measured I‐V characteristics of Cu‐TA metallogel‐based thin‐film metal‐semiconductor (MS) junction devices under irradiation and nonirradiation conditions show a nonlinear rectifying behavior, typical of a Schottky diode (SD). [ABSTRACT FROM AUTHOR]

A nitro-functionalized Cu(II)-based one-dimensional coordination polymer (1D CP) [Cu(nip)(4-phpy)2]n (1) (H2nip = 5-nitroisophthalic acid and 4-phpy = 4-phenylpyridine) was synthesized and characterized by elemental analysis, powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SCXRD). In the solid-state self-assembly of 1, two sets of weak intermolecular forces, CH⋯π interaction among the axially bound 4-phpy ligands and π⋯π interaction among bridging nip ligands from adjacent 1D coordination polymeric chains led to 3D supramolecular packing. Interestingly compound 1 exhibited electrical conductivity in the semiconducting regime and behaved as a Schottky barrier diode. [ABSTRACT FROM AUTHOR]

Two mononuclear iron(III) complexes, [Fe(L1)(N3)] and [Fe(L2)(N3)], {H2L1 = N,N′-bis(3-methoxysalicylidene)diethylenetriamine and H2L2 = N,N′-bis(3-ethoxysalicylidene)diethylenetriamine} have been synthesized and characterized by elemental, spectral and X-ray crystallographic studies. Structural features have been examined in detail that reveal the formation of interesting supramolecular networks generated through weak non-covalent interactions. The current–voltage characteristic curves for an Al/complex Schottky-barrier diode (SBD) exhibit non-ohmic behavior. Important parameters like ideality factor, barrier height and series resistance are measured with the help of thermionic emission (TE) theory. Space-charge-limited current (SCLC) theory is employed to evaluate the charge transport parameters such as effective carrier mobility and transit time for both complexes. Complex 1 is found to be more conductive. To obtain insight into the physical nature of weak non-covalent interactions, Bader's quantum theory of atoms-in-molecules (QTAIM) is used extensively. Additionally, the non-covalent interaction reduced density gradient (NCI-RDG) methods established nicely the presence of such non-covalent intermolecular interactions. [ABSTRACT FROM AUTHOR]

Two new coordination polymers (CPs), namely [Co(adc)(4-ppy)(H2O)2]n, (1) and [Co(adc)(4-bppy)(H2O)2]n, (2) (H2adc = acetylenedicarboxylic acid, 4-ppy = 4-phenylpyridine and 4-bppy = 4-(4-bromophenyl)pyridine), have been synthesized and characterized via numerous techniques including elemental analysis, infrared spectroscopy, powder X-ray diffraction (PXRD), single crystal X-ray diffraction (SCXRD), and thermogravimetric analysis (TGA). Both the compounds form one-dimensional (1D) chain-like structures constructed by linear dicarboxylate and pyridyl-based organic linkers and show significant non-covalent interactions. Both the compounds exhibit electrical conductivity and reveal Schottky barrier diode behavior. However, compound 1 shows a slightly better electrical conductivity (2.61 × 10−5 S m−1) than compound 2 (2.52 × 10−6 S m−1). The optical band gaps of both compounds in the solid state have also been determined via experimental measurements and compared with the theoretical values obtained from DFT calculations. [ABSTRACT FROM AUTHOR]

Here, we analyze inhomogeneities in the barrier height (BH) of Al/Cu5FeS4 Schottky device from the electrical (I – V) measurements with a temperature range between 303 and 408 K. The temperature-dependent performance of our fabricated device is analyzed by using the thermionic emission (TE) theory. Some important diode parameters like BH (Φbo), ideality factor (η), and series resistance (RS) are evaluated from the forward current–voltage characteristic curves. The calculated η and RS of the Schottky barrier diode (SBD) decrease, whereas the Φbo of the device increases with the increase in temperature. The value of Richardson constant (A*) for our material is obtained as 1.94 × 10−4 A cm−2 K−2 in the temperature range 303–408 K, which is found as much lesser than the theoretical value of 29.90 A cm−2 K−2. The discrepancy of A* from the theoretical value has been well explained by TE theory with the assumption of Gaussian distribution (GD) of BHs due to the existence of BH inhomogeneities at metal semiconductor (MS) junction. The obtained values of the mean BH Φbo and the standard deviation σs are 1.026 eV and 173 mV in the corresponding temperature range. The mean BH (1.199 eV) and Richardson constant (29.73 A cm−2K−2) are determined from the modified Richardson plot depending on the inhomogeneity of BHs. Apparent BH consists of mean BH (Φbo) and standard deviation (σs). The σs contributes significantly to the modification of Richardson constant and mean BH. The calculated value of the modified Richardson constant is in close agreement with the theoretical value. From C – V measurements built-in voltage and effective BH of this structure were calculated as a function of frequency. [ABSTRACT FROM AUTHOR]

A hetero-dinuclear cobalt(III)/sodium complex with a compartmental Schiff base ligand has been synthesized and characterized. Cobalt(III) is placed in the inner N2O2 compartment and sodium resides in the outer O2O2′ compartment of the Schiff base. The complex shows interesting C–H⋯π(N3) interactions. The opto-electronic properties of the complex have been studied and it has been found that the complex can be used to construct photosensitive Schottky devices. The solid state UV measurement implies the semiconductor behavior of the complex with an optical band gap energy of 2.85 eV. [ABSTRACT FROM AUTHOR]

A novel mechanically stable supramolecular Co(II)-metallohydrogel has been synthesized. Cobalt(II) nitrate hexahydrate and monoethanolamine, as a low molecular weight organic gelator, are used to get the gel. The mechanical stability of the supramolecular hydrogel was analyzed. The morphology of the supramolecular metallohydrogel was scrutinized. The semiconducting features of the metallohydrogel were studied. The conducting properties of the Co(II)-metallohydrogel establish a Schottky barrier diode type nature. The catalytic nature of the Co(II)-metallohydrogel based room temperature single pot aryl–S coupling reaction was explored. Most interestingly, the Co(II)-metallohydrogel based catalytic aryl–S coupling reaction does not require any column-chromatographic purification protocol to get pure aryl-thioethers. Thus, through this work a semiconducting Schottky barrier diode application and catalytic role in the room temperature single pot aryl–S coupling reaction of a supramolecular Co(II)-metallohydrogel have been explored. [ABSTRACT FROM AUTHOR]

Two novel coordination polymers (CPs) [Zn(cis-1,4-chdc)(4-phpy)]n, (1) and [Zn(cis-1,4-chdc)(py)]n, (2) (1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, 4-phpy = 4-phenylpyridine and py = pyridine) were synthesized and characterized by elemental analysis, infrared spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction and thermogravimetric analyses. Both compounds formed a one-dimensional (1D) chain-like structure constructed by Zn2(CO2)4 paddle-wheel dimers interconnected via double strands of cis-1,4-chdc-bridges, whereby pyridine-based ligands were decorated as arms on both sides of Zn2 dimers. In compound 1, polymeric 1D chains underwent self-assembly via π⋯π stacking interactions among 4-phpy ligands to form a 2D network, whereas this type of interaction was absent in 2. Interestingly, both compounds exhibited electrical conductivity and revealed Schottky barrier diode behavior. However, compound 1 showed better electrical conductivity (1.09 × 10−3 S m−1) with respect to compound 2 (6.01 × 10−5 S m−1) because of π⋯π interactions. [ABSTRACT FROM AUTHOR]

An intriguing rapid self-healing functional Mg(OH)2 metallogel was instantaneously developed through the direct mixing of monoethanolamine and magnesium nitrate hexahydrate as the source of magnesium ions in a water medium at room temperature under atmospheric pressure. The rheological properties of the Mg(OH)2 metallogel were scrutinized, and this revealed the mechanical toughness of the semi-solid metallogel material. The outcome of the rheological experiment showed the self-healing property of the metallogel. The self-healing feature was rapid and it occurred within a few minutes of the insertion of a crack into the metallogel or the association of two separate metallogel parts. The morphology of the metallogel was visualized through field emission scanning electron microscopy and EDX spectral investigations. The experimentally estimated optical band gap suggested the semiconducting nature of the material. The semiconducting nature of the metallogel was further verified from the electrical properties. Finally, a technologically challenging device-type application was also realized by the successful fabrication of a Schottky barrier diode, and different device parameters were investigated to verify the performance. The fabricated diode based on the Mg(II) metallogel showed a very high ON/OFF ratio of 85.52. [ABSTRACT FROM AUTHOR]

(E)-N′-((7-Hydroxy-4-methyl-2-oxo-2H-chromen-8-yl)methylene)picolinohydrazide (H-CPh), a greenish yellow emitter in the solid state, aggregates in DMSO solution upon increasing the percentage of water (>50%) and the maximized emission intensity was reached at 90% water–DMSO medium. Upon excitation at 400 nm in pure aquatic medium (HEPES buffer, pH 7.2) H-CPh shows fluorescence sensitivity to Al3+ (λem, 470 nm) and forms a 1 : 1 complex, [(CPh)Al(OH)(H2O)]NO3, with a limit of detection (LOD) of 6.99 nM. The complex, [(CPh)Al(OH)(H2O)]NO3 shows sensitivity to nitroaromatics by quenching the strong emission of the fluorogenic complex and the LODs are: 2,4-dinitrophenol (DNP), 1.67 μM and 2,4,6-trinitrophenol (TNP) 0.99 μM. The H-CPh is electronically a semiconductor and the experimental (2.78 eV) and the DFT derived (2.75 eV) band gaps are comparable. The H-CPh forms a Schottky diode and its photoconductivity (19.98 × 10−4 S m−1) is three times higher than the dark phase conductivity (6.42 × 10−4 S m−1). [ABSTRACT FROM AUTHOR]

An X-ray characterized tetranuclear nickel(ii)/lead(ii) complex has been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction studies. Single crystal X-ray analysis confirms that the complex contains two [(NiO2)Pb] cores joined with two DMF molecules. The complex shows interesting electrical properties. The optical band gap energy of the synthesized ligand and the complex has been evaluated as 3.87 and 3.08 eV, respectively. The solid state UV measurement implies the semiconductor behavior of the complex. The complex based device has been determined experimentally to behave as a Schottky diode. [ABSTRACT FROM AUTHOR]

A functional supramolecular gel of oxalic acid and monoethanolamine (OXMEA) has been achieved through direct instant mixing of N,N‐dimethyl formamide (DMF) solution of oxalic acid and pure monoethanolamine at room temperature under ambient condition. The rheological analysis established the viscoelastic semi‐solid type nature of mechanically stable OXMEA supramolecular gel. The morphological pattern, imaged through field emission scanning electron microscopic investigation, explores the bean‐seed like hierarchical architecture of the gel network. The semiconducting property of the gel was verified from band gap energy and conductivity estimation. The electrical charge transport property was also analyzed in the form of OXMEA gel based metal‐semiconductor junction thin film device. The obtained nonlinear current‐voltage characteristics of the device signify Schottky barrier diode nature of the synthesized gel. Overall, this work has been proof of development of semiconducting electronic device by OXMEA gel based gel medium. Through the direct mixing of oxalic acid and monoethanolamine with N,N‐dimethylformamide solvent, a stable supramolecular gel (OXMEA) has been achieved. The mechanical stability of the gel was scrutinized by rheological analysis. The intriguing bean‐seed type morphology of OXMEA gel was observed by FESEM study. The experimentally found charge transport parameters of OXMEA‐thin film device are noteworthy to achieve the intriguing semiconductive feature i. e. the Schottky barrier diode application of OXMEA gel at room temperature. [ABSTRACT FROM AUTHOR]

A novel 1D Cd(ii) based coordination polymer (complex 1) has been synthesized involving an 8-aminoquinoline based Schiff base ligand and cyanate ion. It has been characterized by elemental analysis, different spectroscopy methods and X-ray single crystal diffraction technique. Most interestingly it exhibits unique properties like electrical conductivity and photosensitivity which shows its potential in optoelectronic device application. We prove both experimentally and theoretically that electrical conduction under irradiation of visible light increases many fold in comparison with that under dark condition. Our synthesized material based device shows some paramount behaviour under irradiance of light which is obvious in light sensing Schottky devices. The rectification ratio of our complex based device was found to be 12.44 and 27.74 under dark and photoirradiation conditions respectively. The discovery of such type of coordination polymer advances the area of optoelectronic devices. [ABSTRACT FROM AUTHOR]

A new Cu(ii) based one-dimensional coordination polymer (1D CP), [Cu(fum)(4-phpy)2(H2O)] (1) (H2fum = fumaric acid and 4-phpy = 4-phenyl pyridine), has been synthesized and well characterized using elemental analysis, infrared spectra, single crystal X-ray diffraction (SCXRD) techniques, powder X-ray diffraction (PXRD) patterns, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). In the solid state structure, 1D chains are self-assembled through strong intermolecular hydrogen bonding to give a 2D sheet structure. These 2D sheets are further accumulated to fabricate 3D supramolecular aggregates via weak CH…π interactions. The band gap measurement which is equivalent to the HOMO–LUMO gap calculated by density functional theory (DFT) computations confirms the semiconducting properties of the material. To gain insight into the charge transport mechanism of the compound, its mobility, lifetime and diffusion length have been estimated. The analysis indicates that compound 1 may be applied in active electronic devices. Finally, a metal–CP junction Schottky barrier diode has been successfully fabricated and studied in detail. [ABSTRACT FROM AUTHOR]

A Cd(ii) based 2D metal–organic framework (MOF), [Cd(4-bpd)(SCN)2]n (1) where 4-bpd = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, has been synthesized and characterized by standard methods including single crystal X-ray diffraction analysis. When it is sandwiched between ITO coated glass and Al, 1 shows interesting conduction properties. The I–V characteristics of the ITO/1/Al configuration measured in the dark and under illumination of incident light exhibit a highly non-linear rectifying behavior, which signifies its Schottky diode character. The conductivity of the configuration is 2.90 × 10−4 S m−1 and 7.16 × 10−4 S m−1 under dark and photoirradiation conditions, respectively. Different parameters have been analyzed and these indicate that 1 can be a promising candidate for light sensing electronic devices. This material has good sensitivity to the light source when switched on/off. Theoretical calculations have been performed to understand the reason for the enhancement of conductivity under illumination of incident light. It has been found that upon irradiation, slight changes in the bond distances of 4-bpd in 1 occur. These changes are related to the considerable decrease in the energy needed for the allowed electronic transition. This may influence the increase of conductivity along with other factors. [ABSTRACT FROM AUTHOR]

A metal-organic framework (MOF) of cadmium(II) is reported here which is the first example of an experimentally achieved MOF based electronic device, and in the present case it is a Schottky diode. [ABSTRACT FROM AUTHOR]

[Display omitted] • HF treatment on hydrothermally derived TiO 2. • Study Al/TiO 2 Schottky junction. • Device performance increased. • Study mobility, carrier concentration, ideality factor and barrier potential. Having ascertained the improvement of band gap and conductivity of the synthesized TiO 2 after HF treatment under consideration, it occurred to us that the materials may perform as the better Schottky barrier diode. To verify our presumption, we studied the I-V characteristic of the device fabricated in a sandwich configuration of FTO/sample/Al. The comparative studies show better potentiality of the material in subject to study the qualitative and quantitative measures of the Schottky devices. The work is concluded by examined the various characteristic parameters related with performance of device that is fabricated with HF treated and untreated TiO 2. [ABSTRACT FROM AUTHOR]

• Findings of both classical (O‒H•••O) and non-classical (C‒H•••O) hydrogen bonding interactions along with anti-parallel π•••π stacking. • Supramolecular networks inside the title complexes comprise the π-stacked self-assemblies analysed by QTAIM and NCI plot. • Presence of very strong ring motifs in agreement with the MEP analysis. • Fabrication of schottky barrier diode and conductivity studies. Two new complexes [Ni(C 7 H 3 NO 5) (C 15 H 11 N 3)]. 4(H 2 O) (1) and [Cu(C 7 H 3 NO 5) (C 15 H 11 N 3)]. 4(H 2 O) (2) have been synthesized using mixed chelating ligands [4-hydroxypyridine-2,6-dicarboxylic acid (chelidamic acid) (C 7 H 5 NO 5) and 2,2′:6′,2′′-terpyridine (C 15 H 11 N 3)] in aqueous medium. The two complexes were characterized by UV–visible, IR spectroscopy as well as by single-crystal X-ray diffraction analysis. The geometries of both the complexes are distorted octahedral with N 4 O 2 chromophore. The non-covalent interactions found in the solid state architectures of complexes 1 and 2 have been described focusing on π•••π stacking and hydrogen bonding interactions. These non-covalent interactions played an imperative role in building of multi-dimensional supramolecular architectures. These interactions have been explored theoretically by density functional theory (DFT) focusing on the antiparallel π-π stacking in self-assembled dimers and the hydrogen bonding networks mediated by the lattice water molecules. MEP surface calculations combined with QTAIM and NCI plot analysis were used to rationalize and characterize the non covalent interactions involved in the assemblies. The low optical band gaps of the two complexes exhibit semiconducting property leading to potentially fabricate Schottky Barrier Diode. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigates a supramolecular metallogel formed using an ultrasonication technique and employing manganese acetate tetrahydrate as a metal salt, 2-amino terephthalic acid (ATA) as an organic gelator, and N,N′-dimethyl formamide and dimethyl sulfoxide as mixed solvents. The mechanical toughness and viscoelastic parameters of the metallogel material were well demonstrated by rheology-based experimental values of storage and loss moduli with rotational frequency, shear strain, and shear stress of the Mn(II)-metallogel (Mn-ATA). The microstructural analysis along with chemical composition were shown using field emission scanning electron microscopy and energy dispersive X-ray analysis-based elemental research. Analysis of the infrared spectrum aided in determining how Mn-ATA was formed. Electrospray ionization mass investigation of Mn-ATA demonstrated the existence of several metallogel components and their engagement in producing the metallogel structure. Different diode parameters (i.e. photosensitivity, photoconductivity sensitivity, responsivity, specific detectivity, ideality factor, barrier height, and series resistance were measured, revealing the semiconducting property of the metallogel. The current–voltage characteristics of a Mn-ATA-based thin-film type metal–semiconductor junction device demonstrated non-linear rectifying behavior, indicating Schottky diode behavior with dominating electronic-charge transport features. The device displayed an improved rectifying property under illumination, which also implied higher conductivity. The device's measured conductivity in the low-voltage domain (equivalent to ohmic behavior) was 1.03 × 10−5 and 4.12 × 10−5 Sm−1 under darkness and illumination, respectively, implying photo-responsive behavior. [Display omitted] • A supramolecular Mn(II)-metallogel of 2-amino terephthalic acid is prepared. • The microstructural novelty is explored through FESEM investigation. • The mechanical property of the metallogel has been scrutinized. • The semiconducting diode application of the metallogel based systems is investigated. • The photo-responsiveness of the diode has been explored. [ABSTRACT FROM AUTHOR]

An intriguing strategy for the instantaneous synthesis of monoethanolamine and ferric ion based metallohydrogel through direct mixing in water medium has been achieved at room temperature under atmospheric pressure. The mechanical property of the metallohydrogel was investigated through rheological study. The hierarchical architecture of the metallohydrogel was visualized through field emission scanning electron microscopic and EDX spectral investigations. The possible hydrogel formation strategy has been scrutinized through infrared spectroscopic study. Powder X-ray diffraction study of the metallohydrogel has been explored. Optical band gap was estimated which suggests the semiconducting nature of the material. The semiconducting nature of the metallohydrogel was further verified from the electrical property. Finally the technologically challenging device application was realized by the successful fabrication of Schottky barrier diode and different device parameters were estimated to verify the performance. The fabricated diode showed very high On/Off ratio of 375. A monoethanolamine and Fe(III) based metallohydrogel offers an electronic devices of Schottky barrier diode at room temperature. Unlabelled Image • Monoethanolamine and Fe(III) based metallohydrogel has been synthesized. • The mechanical property of the metallohydrogel is investigated. • The morphological patterns have been imaged through the FESEM analyses. • Schottky barrier diode nature of metallohydrogel is explored. [ABSTRACT FROM AUTHOR]

In this report, we have synthesized Bornite (Cu 5 FeS 4 ) material by hydrothermal synthesis technique. The interface characteristics of Al/Cu 5 FeS 4 /FTO Schottky barrier diode (SBD) are investigated by using ac impedance spectroscopy (IS) analysis (under dark condition) and dc current-voltage (I–V) measurements (under dark and light both condition). IS is a powerful tool to identify the interface regions of SBDs. Ac impedance spectra of Al/Cu 5 FeS 4 SBD are recorded in the frequency range 40 Hz-20 MHz during dc bias scanning from -0.6 V to 0.6 V under dark condition. The diode parameter including ideality factor and barrier height is calculated from the conventional I–V measurement based on thermionic emission (TE) theory. Space charge limited current (SCLC) theory has been employed to further exemplify the improved performance of Cu 5 FeS 4 based SBD, which points out that the carrier mobility is enhanced ∼2-fold after irradiation of light. [ABSTRACT FROM AUTHOR]

Molybdenum Tungsten Di-Sulphide is a semiconducting alloy of different TMD (transition metal dichalcogenide) materials that has enormous tunable structural, optical, and electrical attributes. In this research, we have performed the hydrothermal synthesization of Mo 1-x W x S 2 nanocomposites with different molar concentration of tungsten (i.e. x = 0, 0.1, 0.2, 0.3) and fabricated Al/Mo 1-x W x S 2 /ITO structured Schottky Barrier diodes. Characterization of their structural, optical, and charge transport attributes are compared. In this alloy formation, the amount of W (tungsten) concentration has a great impact on the particle size of composites. The transportation of charges via the metal-semiconductor junction is the basis for the superiority of thin film semiconductor devices like the Schottky diode. The diode parameters as well as charge transfer characteristics were analyzed by Impedance Spectroscopy and the theory of SCLC (space charge limited current). The calculated mobility and transit time for the Mo 0.8 W 0.2 S 2 device are 5.65 × 10−4 m2 V−1 s−1 and 1.59 ns respectively. These results are better than the rest of the devices. Dramatic conductivity enhancement for the Mo 0.8 W 0.2 S 2- based Schottky device is observed. As a result, this work not only investigates Al/MoWS 2 interface in detail but also explains the faster and better charge transport of the Mo 0.8 W 0.2 S 2 -based device from a structural perspective. [Display omitted] • Hydrothermal Synthesis of MoWS 2 nanocomposites and comparative study with pure MoS 2. • Fabrication of Al/Mo 1-x W x S 2 /ITO device and investigation of charge transportation. • Significant variation of charge kinetics by incorporating W into MoS 2. • Diode parameters and interfacial properties analyzed by Impedance Spectroscopy. • Mo 0.8 W 0.2 S 2 -based SBD exhibited 1493% improvement in conductivity compared to MoS 2. [ABSTRACT FROM AUTHOR]

In this work, we have prepared copper (II) oxide (CuO) nanoparticles (NPs) via reflux (CuO (R)) and hydrothermal (CuO (H)) methods. The electrical parameters like rectification ratio, ideality factor and barrier height were compared between two synthesized CuO NPs after fabricating Al/CuO/ITO schottky barrier diode (SBD). Under dark, rectification ratio increased by 37% for CuO (H) than CuO (R). In a similar manner, photoresponse also significantly improved by a huge 93%. Impedance Spectroscopy measurements establish that CuO (H) shows better charge transport and lower carrier recombination compared to CuO (R). The enhanced device performance of the hydrothermally synthesized CuO based schottky diode can be attributed to the reduction in lattice defect density and its good thin film properties. [ABSTRACT FROM AUTHOR]

Here we report the temperature dependent performance of Al/rGO-ZnCdS Schottky barrier diode(SBD) in the range of 303 K–453 K. Ideality factor( n ) and Series resistance( R s ) of the SBD decreased, while barrier height (BH)( ϕ b0 ) increased with increasing temperature. Richardson constant ( A ∗ ) was obtained as 2 × 10 −8 A/cm 2 K 2 and 1.4 × 10 −7 A/cm 2 K 2 in the temperature range 303–363 K and 378–423 K respectively, which are much lower than the theoretical value of 32 A/cm 2 K 2 . The strong temperature dependence of BH and the large discrepancy in A ∗ has been precisely explained by assuming a Gaussian distribution (GD) of the BHs due to BH inhomogeneities at the metal-semiconductor interface. The results reveal the existence of a double GD with mean BH values ( ϕ b 0 ‾ ) of 1.47 eV and 1.26 eV and standard deviations( σ s ) of 0.22 V and 0.18 V. The modified activation energy plot of ln ( I 0 / T 2 ) - ( q 2 σ 2 / 2 k 2 T 2 ) yields ϕ b 0 ‾ and A ∗ values as 1.49 and 1.26 eV, and 59.18 A/cm 2 K 2 and 32.29 A/cm 2 K 2 , respectively. Particularly the A ∗ value of 32.29 A/cm 2 K 2 is extremely close to the theoretical value. The analysis confirmed that temperature dependent I - V characteristics of our SBD can be successfully explained with a double GD of the BHs. [ABSTRACT FROM AUTHOR]

• Low molecular weight gelator directed supramolecular Zn(II)-metallogel is developed. • The microstructural pattern of the metallogel has been imaged by FESEM and TEM. • The rheological characterization of the Zn-TA is performed. • Photo-sensitivity of metal-semiconductor junction based Schottky diode are explored. An supramolecular Zn(II)-metallogel (Zn@TA) is formed by ultra-sonication using Zinc(II) acetate dihydrate and terephthalic acid in N,N-dimethyl formamide medium. The visco-elastic nature of semi-solid Zn@TA metallogel is established through rheological investigations. Field Emission Scanning Electron Microscopic (FESEM) and Transmission Electron Microscopic (TEM) images establish the morphology and network of metallogel. The gel formation-strategy is scrutinized through Mass and infrared spectral analysis. Promising electronic charge transport property and photo-sensitivity of metal-semiconductor junction based Schottky diode are explored by metallogel-based devices. The direct optical band gap of Zn@TA is calculated as 3.19 eV. Significantly, the electrical conductivities of Zn@TA based semiconducting device were measured as 7.77 × 10−6 and 17.66 × 10−6S m−1 under no-light and light conditions, respectively. Rectification ratio of that device under dark at ±2 V was computed as 37.06, whereas with AM 1.5 G (light-irradiation) condition the ratio was found as 79.63. Terephthalic acid based a supramolecular Zn(II)-metallogel has been synthesized through ultra-sonication technique and the metallogel is being executed for fabricating the photo-responsive metal-semiconductor junction based Schottky diode device with marked Rectification Ratios. [Display omitted] [ABSTRACT FROM AUTHOR]

An efficient supramolecular metallogel of Cobalt(II) has been synthesized through the ultra-sonication technique. Cobalt(II)-salt (Cobalt acetate tetrahydrate), organic acid like terephthalic acid along with N,N-dimethyl formamide solvent are the key ingredients of the Co(II)-metallogel. The rheology-based experimental values of storage and loss modulus of the Co(II)-metallogel prove the mechanical efficiency of the metallogel-material. The chemical compositions are found through elemental investigations. The infrared spectral results help to realize the metallogel formation strategy. The electrical characteristics of the synthesized metallogel have been properly investigated. The semiconducting feature of the metallogel-material has been experimentally verified. The measured current-voltage characteristics of Cobalt(II)-metallogel (Co-TA) based thin film type metal-semiconductor (MS) junction-device shows a non-linear rectifying behaviour, representing a Schottky diode (SD) performance with promising electronic charge transport property. An efficient supramolecular metallogel of Co(II) (Co-TA) has been developed by mixing of Cobalt(II)-salt and terephthalic acid in N,N-dimethyl formamide solvent, and the mechanically flexible metallogel based thin film metal-semiconductor (MS) junction device is fabricated and characterized by I–V measurement which typically dictates a Schottky diode (SD) behaviour with predominant charge transport property. [Display omitted] • Synthetic strategy of an organic acid based Co(II)-metallogel has been achieved. • STEM based microstructural and elemental studies have been performed. • The mechanical stability of the metallogel has been tested by rheological experiments. • The metallogel-based thin film type metal-semiconductor (MS) junction-device has been fabricated. • The diode-device shows Schottky diode performance with promising electronic charge transport property. [ABSTRACT FROM AUTHOR]

In this work, we report two different synthesis process of semiconducting ZnO which modifies the morphology of the ZnO materials and its impact in photosensing Schottky diode. Hydrothermal and co-precipitation method were used to synthesize ZnO which gave rise to rod like (ZnO HT) and particle like ZnO (ZnO COP), respectively. From UV–Vis analysis, ZnO HT exhibited greater optical absorption. Al/ZnO (HT and COP)/ITO Schottky diodes were fabricated and the photoresponse as well as diode parameters were investigated by current-voltage and capacitance voltage measurements. Then charge transport properties were determined by space charge limited current theory and impedance spectroscopy. The results showed that the ZnO HT based SBD delivered a responsivity of 0.144 A/W which is 121% higher than the responsivity showed by ZnO COP based SBD (0.065 A/W). The specific detectivity of ZnO HT was measured at 7.54 × 109 Jones, a noticeable improvement from the 4.10 × 109 Jones of ZnO COP. The carrier mobility, lifetime and diffusion length of the ZnO HT based device were found to be 0.0014 cm2 V−1s−1, 72.35 μs and 72.37 μm respectively which are again superior to its counterpart. The faster and better charge transport is facilitated by the rod like morphology of the former. The study demonstrates improved device performance of rod like ZnO based Schottky diode and provides detail analysis of the Al/ZnO interface which can be beneficial for future research on metal-semiconductor junction. [Display omitted] [ABSTRACT FROM AUTHOR]

A new halopyridine appended Co(II) based coordination polymer (CP), [Co(3-clpy) 2 (fum) 2 (H 2 O) 2 ] n (1) {3-clpy = 3-Chloropyridine and H 2 fum = fumaric acid} has been synthesized and characterized by elemental analysis and single crystal X-ray diffraction (SCXRD) technique. The carboxylate linker, H 2 fum propagates to form of a one dimensional (1D) polymeric structure. The 1D chains are interconnected via hydrogen bonding interactions leading to 2D sheet. The 3-clpy ligands of one chain facilitate π⋯π stacking interactions with adjacent chain leading to 3D supramolecular assembly. Hirshfeld surface analysis has also been performed to check the non covalent interactions in the crystal packing. Compound 1 shows electrical conductivity and reveals Schottky barrier diode behavior. [Display omitted] A new halopyridine appended Co(II) based coordination polymer (CP), [Co(3-clpy) 2 (fum) 2 (H 2 O) 2 ] n (1) {3-clpy = 3-Chloropyridine and H 2 fum = fumaric acid} has been synthesized and characterized by elemental analysis and single crystal X-ray diffraction (SCXRD) technique. Compound 1 crystallizes in monoclinic space group P 2 1 / c. Herein, the ditopic linker H 2 fum acts as bridging ligand in the formation of a one dimensional (1D) CP. The 1D chains are interconnected via hydrogen bonding interactions leading to 2D sheet. The 3-clpy ligands of one chain facilitate π⋯π stacking interactions with adjacent chain leading to 3D supramolecular assembly which generally promotes better charge transport in the material. Hirshfeld surface analysis has also been performed to check the non covalent interactions in the crystal packing. Interestingly, the compound 1 shows electrical conductivity and reveals Schottky barrier diode behavior. [ABSTRACT FROM AUTHOR]

Copper Indium Selenide (CuInSe 2) has been synthesized by solvothermal synthesis method. The Schottky diode (SD) has been fabricated by using the material and the interface characteristics of Al/CuInSe 2 /ITO have been investigated with the help of ac impedance spectroscopy (IS) analysis (under dark condition) and dc current-voltage (I–V) measurements (under both dark and photo condition). IS is a very important and powerful technique to investigate and analyze the impedance at the boundary regions of SDs. Ac impedance spectra of Al/CuInSe 2 SD have been recorded in the wide range of frequency from 40 Hz to 20 MHz during dc bias scanning from −0.5 V to 0.5 V under dark condition. From forward I–V characteristics, important parameters such as ideality factor (η), photosensitivity, barrier height (Φ b), series resistance (R S) of SD were obtained under dark and photo condition. The photosensitivity of the Al/CuInSe 2 SD was found to be 3.36. For better realization of charge transport phenomena through the MS junction, space charge limited current (SCLC) theory has been employed. The effective mobility of the carrier is evaluated in dark and photo condition as 0.42 × 10−3 m2V−1s−1 and 2.11 × 10−3 m2V−1s−1 respectively. It has been observed that the mobility is improved 5 times under illumination compared to the dark condition. • Copper Indium Selenide (CuInSe 2) was synthesized by solvothermal synthesis method. • Electrical properties of Al/CuInSe 2 Schottky diode were studied by using I-V and Impedance Spectroscopy analysis. • Metal-semiconductor interfaces were properly identified with the help of Impedance Spectroscopy analysis. • The Impedance Spectroscopy data was interpreted with the help of a proper ac equivalent circuit. • The charge transport mechanism through Al/CuInSe 2 was analyzed by utilizing space charge limited current (SCLC) theory. [ABSTRACT FROM AUTHOR]

In this paper we report the photophysical and electrical characteristics of our synthesized imidazole derivative namely l-alkyl-2-(arylazo) imidazole (AAI) organized in Langmuir-Blodgett (LB) films towards the development of organic Schottky barrier diode (SBD). Presence of long alkyl chain in the molecule make it suitable for LB technology and may favour aggregations of the molecules in LB films under barrier compression. The interfacial properties of the formation of Langmuir monolayer of AAI at air-water interface have been studied by surface pressure versus area per molecule (π-A) isotherm and compressibility modulus. Hysteresis study of the isotherm confirmed the formation of stable monolayer of AAI molecular assemblies at air-water interface. The aggregation of AAI molecules in LB films is confirmed by Ultraviolet–visible (UV–vis) absorption, fluorescence emission spectroscopy and Atomic force microscopic (AFM) methods. AAI molecules also formed network type morphology in LB films due to their closure association and aggregations or cluster of molecules which were evidenced by AFM technique. The compression induced aggregations of AAI is reflected as broadened nature of monomeric absorption band along with the emergence of a new absorption band at longer wavelength side for LB film deposited at surface pressure of 25 mN/m. The optical absorption bands of AAI and the corresponding transitions between different electronic states have been simulated by density functional theoretical (DFT) analysis and is compared with the experimental results. Nonlinear behaviour of the current-voltage characteristics and various relevant electrical parameters of the LB film device at the interface of metal electrode (gold) satisfy the necessary conditions showing the properties of a Schottky barrier diode. Image 1 • l-alkyl-2-(arylazo) imidazole (AAI) forms Langmuir monolayer at air-water interface. • Barrier compression induces π-π stacking interactions between the aromatic moieties. • Organic Schottky barrier diode is fabricated from AAI based Langmuir-Blodgett film. • AFM and Photophysical studies support the formation of aggregates of AAI in LB film. • The ideality factor of the fabricated Schottky device is slightly greater than unity. [ABSTRACT FROM AUTHOR]

Graphene and its nanocomposites with different semiconductor materials have attracted significant research interest in the last decade due to their improved performance in various fields. In this report, SnO 2 and a reduced graphene oxide (rGO)-SnO 2 composite is synthesized via hydrothermal method. Structural, optical and electrical characterization of the material is performed. Incorporation of rGO increases the light absorption and reduces the band gap of SnO 2. Schottky barrier formation at metal-semiconductor junction is important for various applications. Here, we describe the performance of SnO 2 and rGO-SnO 2 based Schottky diode. Important diode parameters like rectification ratio, ideality factor, barrier height and series resistances are calculated from forward Current density-voltage (J-V) characteristics. rGO-SnO 2 shows much better performance compared to SnO 2. Analysis of Photoresponse behavior reveals that rGO-SnO 2 shows photosensitivity of about 9.95 which is higher than that of SnO 2 (2.42). After incorporation of rGO, other diode parameters and transport properties were also improved. To gain better insight on charge transport properties, space charge limited current theory has been utilized. In rGO-SnO 2 , carrier mobility is increased by 62% compared to SnO 2 , implying that rGO-SnO 2 has better charge transport due to enhanced electron hole separation which is attribute to the presence of graphene. Image 1 • I–V characteristics is well described by Cheung's model. • Charge transport parameters are obtained using Space charge limited current theory. • The role of rGO in enhancement of electron transfer are clarified from Nyquist plot. [ABSTRACT FROM AUTHOR]

• MoS 2 and MoS 2 -Graphene (MGC) composite have been synthesized by hydrothermal process. • Electrical properties of Al/MoS 2 /ITO and Al/MGC/ITO Schottky diode were studied by conventional current-voltage measurement. • The photosensitivity of composite based diode increased by almost 33 times compared to pure MoS 2 based diode. • The charge transport mechanism of Schottky barrier diode was discussed by employing space charge limited current (SCLC) theory. In this work, MoS 2 and MoS 2 -Graphene (MGC) composite have been synthesized by hydrothermal process followed by their structural, optical and electrical characterization. The current density-voltage measurements have been performed at room temperature by fabricating Al/MoS 2 and/or MGC/ITO configured sandwich structured metal-semiconductor (MS) thin film Schottky devices. Under light and dark conditions, various parameters of our synthesized material based devices like rectification ratio, series resistance, barrier height, etc. have been measured and compared between the two. All the measured electrical properties show improvement for the composite based diodes, noteworthy the photosensitivity which has been increased by almost 33 times, signifying its potential application in photosensitive devices. [ABSTRACT FROM AUTHOR]