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Element doping and interface modification strategy are effective methods to regulate the electrical properties of SnO2 electron transport material, SnO2/perovskite (PVK) interface, and PVK crystal growth. Herein, rubidium fluoride (RbF) is introduced into SnO2 colloidal dispersion, and then an ultra‐thin layer of 4‐carboxy‐3‐fluorobenzoboric acid (FBCA) is applied to the SnO2 layer surface. This synergistic modification strategy can improve the electrical conductivity of the electron transport layer, increase the chemical connection of the buried interface, improve the crystallization and grain growth of PVK, and thus promote the performance and stability of devices. The results show that the PVK solar cells (PSCs) with the synergistic‐modified SnO2 electron transport material (M‐SnO2) obtain an optimum power conversion efficiency of 21.92% and the unencapsulated PSCs sustain 91% and 87% of the original value, which stored in a nitrogen atmosphere and ambient atmosphere (25 ± 5 °C, 30–50% relative humidity) more than 1000 h, respectively. [ABSTRACT FROM AUTHOR]

One of the most essential chemical processes that is utilized in the manufacturing of a great deal of contemporary goods is called heterogeneously catalyzed reactions, and it is also one of the most fascinating. Metallic nanostructures are heterogeneous catalysts for range reactions due to their huge surface area, large assembly of active surface sites, and quantum confinement effects. Unprotected metal nanoparticles suffer from irreversible agglomeration, catalyst poisoning, and limited life cycle. To circumvent these technical disadvantages, catalysts are frequently spread on chemically inert materials like as mesoporous Al2O3, ZrO2, and different types of ceramic material. In this research, plentiful bauxite residue is used to create a low-cost alternative catalytic material. We have hydrogenated p-Nitrophenol to p-Aminophenol on bauxite residue (BR) supported silver nanocomposites (Ag NCs). The phase and crystal structure, bond structure and morphological analysis of the developed material will be done XRD, FTIR, and SEM-EDX respectively. The ideal conditions were 150 ppm of catalyst, 0.1 mM of p-NP, and 10 minutes overall up-to 99% conversion of p-NP to p-AP. A multi-variable predictive model created using Response Surface Methodology (RSM) and a data-based Artificial Neural Network (ANN) model were found to be the best ways to predict the maximum conversion efficiency. ANN models predicted efficiency more accurately than RSM models, and the strong agreement between model predictions and experimental data was indicated by their low relative error (RE0.10), high regression coefficient (R2>0.97), and Willmott-d index (dwill-index > 0.95) values. [ABSTRACT FROM AUTHOR]

Hybridisation of the cavity modes and the excitons to polariton states together with the coupling to the vibrational modes determine the linear optical properties of organic semiconductors in microcavities. In this article we compute the refractive index for such system using the Holstein–Tavis–Cummings model and determine then the linear optical properties using the transfer matrix method. We first extract the parameters for the exciton in our model from fitting to experimentally measured absorption of a 2,7-bis[9,9-di(4-methylphenyl)-fluoren-2-yl]-9,9-di(4-methylphenyl) fluorene (TDAF) molecular thin film. Then we compute the reflectivity of such a thin film in a metal clad microcavity system by including the dispersive microcavity mode to the model. We compute susceptibility of the model systems evolving just a single state vector by using the non-Markovian quantum state diffusion. The computed location and height of the lower and upper polaritons agree with the experiment within the estimated errorbars for small angles (≤ 30 °) . For larger angles the location of the polariton resonances are within the estimated error. [ABSTRACT FROM AUTHOR]

Optical control is achieved on the excited state energy transfer between spatially separated donor and acceptor molecules, both coupled to the same optical mode of a cavity. The energy transfer occurs through the formed hybrid polaritons and can be switched on and off by means of ultraviolet and visible light. The control mechanism relies on a photochromic component used as donor, whose absorption and emission properties can be varied reversibly through light irradiation, whereas in-cavity hybridization with acceptors through polariton states enables a 6-fold enhancement of acceptor/donor contribution to the emission intensity with respect to a reference multilayer. These results pave the way for synthesizing effective gating systems for the transport of energy by light, relevant for light-harvesting and light-emitting devices, and for photovoltaic cells. [ABSTRACT FROM AUTHOR]

Abstract Production of liquid fertilizers containing nitrogenous nutrients and biostimulants from sewage sludge (SS-NB) has been attracting increasing attention due to its excellent fertilization effect and resource recycling attributes. To better understand the functional effects of nutrients and biostimulants in SS-NB on soil, the adsorption capacity and mechanism of straw biochar (SB) and wood chip biochar (WCB) for alkaline and neutral SS-NB components were investigated. The adsorption of total organic carbon (TOC) from alkaline and neutral SS-NB by WCB was 61.14% and 89.73%, respectively, higher than that by SB, which was 56.25% and 83.36%. Moreover, TOC from neutral SS-NB was more readily adsorbed, especially for fulvic and humic acids. SB had a strong adsorption capacity for calcium ions and nitrogen (TKN, nitrate N, protein, amino acid) and released large amounts of P. In addition, WCB and SB showed a strong affinity for macromolecules (proteins) and reducing substances (lignin and lipids) and excellent fixation ability for phytohormones and allelochemicals. However, WCB adsorbed more types of molecular substances than SB while maintaining a high immobilization rate. Analysis of the adsorption mechanism showed that surface amino groups of the biochar were involved in adsorption, while WCB had additionally high adsorption efficiencies through pore adsorption, hydrogen bonding adsorption and pore size-exclusion effects. The study revealed that biochar can be used as an efficient adsorption carrier for SS-NB to improve soil fertility management. Graphical Abstract

Abstract In materials science, accurately computing properties like viscosity, melting point, and glass transition temperatures solely through physics-based models is challenging. Data-driven machine learning (ML) also poses challenges in constructing ML models, especially in the material science domain where data is limited. To address this, we integrate physics-informed descriptors from molecular dynamics (MD) simulations to enhance the accuracy and interpretability of ML models. Our current study focuses on accurately predicting viscosity in liquid systems using MD descriptors. In this work, we curated a comprehensive dataset of over 4000 small organic molecules’ viscosities from scientific literature, publications, and online databases. This dataset enabled us to develop quantitative structure–property relationships (QSPR) consisting of descriptor-based and graph neural network models to predict temperature-dependent viscosities for a wide range of viscosities. The QSPR models reveal that including MD descriptors improves the prediction of experimental viscosities, particularly at the small data set scale of fewer than a thousand data points. Furthermore, feature importance tools reveal that intermolecular interactions captured by MD descriptors are most important for viscosity predictions. Finally, the QSPR models can accurately capture the inverse relationship between viscosity and temperature for six battery-relevant solvents, some of which were not included in the original data set. Our research highlights the effectiveness of incorporating MD descriptors into QSPR models, which leads to improved accuracy for properties that are difficult to predict when using physics-based models alone or when limited data is available. Graphical Abstract

Exploring organic semiconductor gas sensors with high sensitivity and selectivity is crucial for the development of sensor technology. Herein, for the first time, a promising chemiresistive organic polymer P‐BNT based on a novel π‐conjugated triarylboron building block is reported, showcasing an excellent responsivity over 30 000 (Ra/Rg) against 40 ppm of NH3, which is ≈3300 times higher than that of its B‐N organic small molecule BN‐H. More importantly, a molecular induction strategy to weaken the bond dissociation energy between polymer and NH3 caused by strong acid‐base interaction is further executed to optimize the response and recovery time. As a result, the BN‐H/P‐BNT system with rapid response and recovery times can still exhibit a high responsivity of 718, which is among the highest reported NH3 chemiresistive sensors. Supported by in situ FTIR spectroscopy and theoretical calculations, it is revealed that the N‐H fractions in BN‐H small molecule promoted the charge distribution on phenyl groups, which increases charge delocalization and is more conducive to gas adsorption in such molecular systems. Notably, these distinctive small molecules also promoted charge transfer and enhanced electron concentration of the P‐BNT sensing polymer, thus achieving superior B‐N‐containing organic molecules with excellent sensing performance. [ABSTRACT FROM AUTHOR]

Solar radiation that arrives on the surface of Mars interacts with organic molecules present in the soil. The radiation can degrade or transform the organic matter and make the search for biosignatures on the planet's surface difficult. Therefore, samples to be analyzed by instruments on board Mars probes for molecular content should be selectively chosen to have the highest organic preservation content. To support the identification of organic molecules on Mars, the behavior under UV irradiation of two organic compounds, undecanoic acid and L-phenylalanine, in the presence of vermiculite and two chloride salts, NaCl and MgCl, was studied. The degradation of the molecule's bands was monitored through IR spectroscopy. Our results show that, while vermiculite acts as a photoprotective mineral with L-phenylalanine, it catalyzes the photodegradation of undecanoic acid molecules. On the other hand, both chloride salts studied decreased the degradation of both organic species acting as photoprotectors. While these results do not allow us to conclude on the preservation capabilities of vermiculite, they show that places where chloride salts are present could be good candidates for in situ analytic experiments on Mars due to their organic preservation capacity under UV radiation. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have made significant strides in recent years. However, there are still challenges in terms of photoelectric conversion efficiency and long-term stability associated with perovskite solar cells. The presence of defects in perovskite materials is one of the important influencing factors leading to subpar film quality. Adopting additives to passivate defects within perovskite materials is an effective approach. Therefore, we first discuss the types of defects that occur in perovskite materials and the mechanisms of their effect on performance. Then, several types of additives used in perovskite solar cells are discussed, including ionic compounds, organic molecules, polymers, etc. This review provides guidance for the future development of more sustainable and effective additives to improve the performance of solar cells. [ABSTRACT FROM AUTHOR]

In materials science, accurately computing properties like viscosity, melting point, and glass transition temperatures solely through physics-based models is challenging. Data-driven machine learning (ML) also poses challenges in constructing ML models, especially in the material science domain where data is limited. To address this, we integrate physics-informed descriptors from molecular dynamics (MD) simulations to enhance the accuracy and interpretability of ML models. Our current study focuses on accurately predicting viscosity in liquid systems using MD descriptors. In this work, we curated a comprehensive dataset of over 4000 small organic molecules’ viscosities from scientific literature, publications, and online databases. This dataset enabled us to develop quantitative structure–property relationships (QSPR) consisting of descriptor-based and graph neural network models to predict temperature-dependent viscosities for a wide range of viscosities. The QSPR models reveal that including MD descriptors improves the prediction of experimental viscosities, particularly at the small data set scale of fewer than a thousand data points. Furthermore, feature importance tools reveal that intermolecular interactions captured by MD descriptors are most important for viscosity predictions. Finally, the QSPR models can accurately capture the inverse relationship between viscosity and temperature for six battery-relevant solvents, some of which were not included in the original data set. Our research highlights the effectiveness of incorporating MD descriptors into QSPR models, which leads to improved accuracy for properties that are difficult to predict when using physics-based models alone or when limited data is available. [ABSTRACT FROM AUTHOR]

Photosensitizer systems play a crucial role in light absorption and charge transfer processes. Designing and selecting dye molecules with exceptional photoelectric features remains a significant scientific challenge in the realm of solar cell research. The paper explores the photovoltaic properties of two D-A'-π-A dyes (CS-70 and CS-72) both individually and after co-sensitization with chlorophyll derivatives, utilizing density functional theory (DFT) and time-dependent density-functional theory (TD-DFT) methods. The monomeric dye molecules share the same donor and conjugated bridge but differ in their auxiliary receptors (benzothiadiazole and naphthobisthiadiazole). Firstly, the study investigates the impact of various auxiliary acceptors on the properties of the dye molecules by analyzing their geometrical structure, frontier molecular orbitals, spectral properties, chemical reaction parameters, intramolecular charge transfer, electron injection, density of projected states, and dye regeneration. A detailed explanation for the superior performance of CS-72 is provided. Furthermore, a solar cell evaluation model was developed for the short circuit current density (Jsc), open circuit voltage (Voc), and photoelectric conversion efficiency (PCE) of the single dye molecule. Subsequently, simulations of the co-sensitized molecules with chlorophyll are performed, focusing on structure, excited state properties and charge transfer, suggesting that co-sensitization enhances spectral properties, light-trapping, and regeneration abilities, and long-range charge transfer between the dye molecules and chlorophyll can be found. The results also demonstrate that the Jsc of the co-sensitized molecules were improved, which facilitates the realization of a higher PCE. This study provides theoretical support for the potential of co-sensitizing dye molecules with chlorophyll to enhance solar cell efficiency, offering valuable insights for the future development of green, cost-effective, and efficient solar cells.

We selected 145 reference organic molecules that include model fragments used in computer-aided drug design. We calculated 158 conformational energies and barriers using force fields, with wide applicability in commercial and free softwares and extensive application on the calculation of conformational energies of organic molecules, e.g. the UFF and DREIDING force fields, the Allinger's force fields MM3-96, MM3-00, MM4-8, the MM2-91 clones MMX and MM+, the MMFF94 force field, MM4, ab initio Hartree–Fock (HF) theory with different basis sets, the standard density functional theory B3LYP, the second-order post-HF MP2 theory and the Domain-based Local Pair Natural Orbital Coupled Cluster DLPNO-CCSD(T) theory, with the latter used for accurate reference values. The data set of the organic molecules includes hydrocarbons, haloalkanes, conjugated compounds, and oxygen-, nitrogen-, phosphorus- and sulphur-containing compounds. We reviewed in detail the conformational aspects of these model organic molecules providing the current understanding of the steric and electronic factors that determine the stability of low energy conformers and the literature including previous experimental observations and calculated findings. While progress on the computer hardware allows the calculations of thousands of conformations for later use in drug design projects, this study is an update from previous classical studies that used, as reference values, experimental ones using a variety of methods and different environments. The lowest mean error against the DLPNO-CCSD(T) reference was calculated for MP2 (0.35 kcal mol−1), followed by B3LYP (0.69 kcal mol−1) and the HF theories (0.81–1.0 kcal mol−1). As regards the force fields, the lowest errors were observed for the Allinger's force fields MM3-00 (1.28 kcal mol−1), ΜΜ3-96 (1.40 kcal mol−1) and the Halgren's MMFF94 force field (1.30 kcal mol−1) and then for the MM2-91 clones MMX (1.77 kcal mol−1) and MM+ (2.01 kcal mol−1) and MM4 (2.05 kcal mol−1). The DREIDING (3.63 kcal mol−1) and UFF (3.77 kcal mol−1) force fields have the lowest performance. These model organic molecules we used are often present as fragments in drug-like molecules. The values calculated using DLPNO-CCSD(T) make up a valuable data set for further comparisons and for improved force field parameterization. [ABSTRACT FROM AUTHOR]

Abstract Exploring organic semiconductor gas sensors with high sensitivity and selectivity is crucial for the development of sensor technology. Herein, for the first time, a promising chemiresistive organic polymer P‐BNT based on a novel π‐conjugated triarylboron building block is reported, showcasing an excellent responsivity over 30 000 (Ra/Rg) against 40 ppm of NH3, which is ≈3300 times higher than that of its B‐N organic small molecule BN‐H. More importantly, a molecular induction strategy to weaken the bond dissociation energy between polymer and NH3 caused by strong acid‐base interaction is further executed to optimize the response and recovery time. As a result, the BN‐H/P‐BNT system with rapid response and recovery times can still exhibit a high responsivity of 718, which is among the highest reported NH3 chemiresistive sensors. Supported by in situ FTIR spectroscopy and theoretical calculations, it is revealed that the N‐H fractions in BN‐H small molecule promoted the charge distribution on phenyl groups, which increases charge delocalization and is more conducive to gas adsorption in such molecular systems. Notably, these distinctive small molecules also promoted charge transfer and enhanced electron concentration of the P‐BNT sensing polymer, thus achieving superior B‐N‐containing organic molecules with excellent sensing performance.

The forward osmosis (FO) process is currently being studied more despite other energy-consuming processes. In addition, several works show the performance of FO membranes as its major challenges, the study of the rejection of different molecules, energy consumption, and modelling of different objectives related to this process. The main purpose of our study was to evaluate the impact of the FO membranes characteristics on the rejection of organic molecules (neutral) by modelling of the latter. However, the current work deals with the application of Support Vector Machines (SVM) for predicting the rejection of organic molecules (53) by the FO membranes. In addition, the SVM model was compared with two other models: Artificial Neural Network (ANN) and Multiple Linear Regression (MLR). The coefficient of correlation (R) for the testing data was applied to display the best SVM model. The SVM model generated with Radial Basis Function (RBF) as the kernel function showed the best R value equal to 0.8526. MLR and ANN models had R values of 0.7630 and 0.8723, respectively.

Our ability to perceive the correlation of different substances in the world is one of the key aspects of human intelligence. The passing of this faculty to artificial intelligence (AI) represents arguably one of the long-standing challenges in the application of AI to scientific problems. To meet this challenge in the burgeoning field of AI for chemistry, we may adopt the paradigm of knowledge graph. Herein, focusing on catalytic chemical reactions, we have developed a semantic knowledge graph framework based on both structured and unstructured data, the latter of which are extracted from the text of 220,000 articles on catalysts for organic molecules. The framework captures the latent knowledge of reactant-catalyst-product relationships and can therefore provide accurate recommendation on potential catalysts for targeted reaction, which especially facilitates the research involving large molecules. This study presents a viable pathway towards the implementation of literature-based data management in a catalyst recommendation platform.

Perovskite solar cells have made significant strides in recent years. However, there are still challenges in terms of photoelectric conversion efficiency and long-term stability associated with perovskite solar cells. The presence of defects in perovskite materials is one of the important influencing factors leading to subpar film quality. Adopting additives to passivate defects within perovskite materials is an effective approach. Therefore, we first discuss the types of defects that occur in perovskite materials and the mechanisms of their effect on performance. Then, several types of additives used in perovskite solar cells are discussed, including ionic compounds, organic molecules, polymers, etc. This review provides guidance for the future development of more sustainable and effective additives to improve the performance of solar cells.

Photovoltaics has become one of the emerging alternatives to progressively supply/replace conventional energy sources, considering the potential exploitation of solar energy. Depending on the nature of the light harvester to influence on its light-absorption capability and the facility to produce electricity, different generations of solar devices have been fabricated. Early studies of organic molecules (dye sensitizers) with good absorption coefficients, going through metal chalcogenides and, lastly, the timely emergence of halide perovskites, have promoted the development of novel and low-cost solar cells with promising photoconversion efficiency (PCE), close to the well-established Si-based devices. However, main drawbacks such as the degradation/photocorrosion of the active layer, the existence of intrinsic defect sites, and the inherent toxicity of the material due to the presence of some harmful elements have blocked the future commercialization of the above kind of solar cells. In this review, we highlight the current progress in achieving efficient photomaterials for organic, chalcogenides and halide perovskites-based solar cells with the purpose of achieving high PCE values, some of which are breakthroughs in this research topic, and the diverse approaches used to extend the stability of the active layer and improve the performance of the solar devices. [ABSTRACT FROM AUTHOR]

Two‐dimensional nanomaterials, as one of the most widely used substrates for energy storage devices, have achieved great success in terms of the overall capacity. Despite the extensive research effort dedicated to this field, there are still major challenges concerning capacitance modulation and stability of the 2D materials that need to be overcome. Doping of the crystal structures, pillaring methods and 3D structuring of electrodes have been proposed to improve the material properties. However, these strategies are usually accompanied by a significant increase in the cost of the entire material preparation process and also a lack of the versatility for modification of the various types of the chemical structures. Hence in this work, versatile, cheap, and environmentally friendly method for the enhancement of the electrochemical parameter of various MXene‐based supercapacitors (Ti3C2, Nb2C, and V2C), coated with functional and charged organic molecules (zwitterions—ZW) is introduced. The MXene‐organic hybrid strategy significantly increases the ionic absorption (capacitance boost) and also forms a passivation layer on the oxidation‐prone surface of the MXene through the covalent bonds. Therefore, this work demonstrates a new, cost‐effective, and versatile approach (MXene‐organic hybrid strategy) for the design and fabrication of hybrid MXene‐base electrode materials for energy storage/conversion systems. [ABSTRACT FROM AUTHOR]

Over the past few decades, molecular self-assembly has witnessed tremendous progress in a variety of biosensing and biomedical applications. In particular, self-assembled nanostructures of small organic molecules and peptides with intriguing characteristics (e.g., structure tailoring, facile processability, and excellent biocompatibility) have shown outstanding potential in the development of various biosensors. In this review, we introduced the unique properties of self-assembled nanostructures with small organic molecules and peptides for biosensing applications. We first discussed the applications of such nanostructures in electrochemical biosensors as electrode supports for enzymes and cells and as signal labels with a large number of electroactive units for signal amplification. Secondly, the utilization of fluorescent nanomaterials by self-assembled dyes or peptides was introduced. Thereinto, typical examples based on target-responsive aggregation-induced emission and decomposition-induced fluorescent enhancement were discussed. Finally, the applications of self-assembled nanomaterials in the colorimetric assays were summarized. We also briefly addressed the challenges and future prospects of biosensors based on self-assembled nanostructures. [ABSTRACT FROM AUTHOR]

We present a simple method for modification of 2D materials by drop-casting of the organic molecule in solution on the 2D material under ambient conditions. Specifically, we investigated the adsorption of 6-(4,5-Dihydro-1H-imidazol-3-ium-2-yl)-2-(naphthalene-2-yl)benzothiazole methanesulfonate (L63MS) organic molecule on 2D MoS 2 . To better understand the effect of the organic molecule on the 2D material, we also investigated the impact of solvents alone on the materials' properties. The MoS 2 samples were synthesized using ambient pressure chemical vapor deposition. Atomic force microscopy, Raman spectroscopy, photoluminescence spectroscopy and optical microscopy were used to characterize the samples. The measurements were performed after synthesis, after the drop-casting of solvents and after the drop-casting of organic molecule solutions. Our results indicate that the used organic molecule effectively adsorbs on and prompts discernible changes in the (opto)electronic properties of the 2D material. These changes encompass variations in the Raman spectra shape, alterations in the photoluminescence (PL) signal characteristics and modifications in excitonic properties. Such alterations can be linked to various phenomena including doping, bandgap modifications, introduction or healing of defects and that the solvent plays a crucial role in the process. Our study provides insights into the modification of 2D materials under ambient conditions and highlights the importance of solvent selection in the process. [ABSTRACT FROM AUTHOR]

Indole analogues are very significant and useful heterocycles, with numerous applications in synthetic organic chemistry, material chemistry, medicinal chemistry, and natural product chemistry. Based on existing data, researchers have been focusing on developing indole-based molecules with new biological and pharmacological effects, since many well-known drugs like tadalafil, sumatriptan, rizatriptan, Fluvastatin etc have indole core. In this review article, we have described the general features and reactivity pattern at different positions of indole ring. In addition to this, different synthetic approaches for the preparation of a series of biologically as well as synthetically challenging complex heterocyclic molecules having indole is also discussed. [ABSTRACT FROM AUTHOR]

The forward osmosis (FO) process is currently being studied more despite other energy-consuming processes. In addition, several works show the performance of FO membranes as its major challenges, the study of the rejection of different molecules, energy consumption, and modelling of different objectives related to this process. The main purpose of our study was to evaluate the impact of the FO membranes characteristics on the rejection of organic molecules (neutral) by modelling of the latter. However, the current work deals with the application of Support Vector Machines (SVM) for predicting the rejection of organic molecules (53) by the FO membranes. In addition, the SVM model was compared with two other models: Artificial Neural Network (ANN) and Multiple Linear Regression (MLR). The coefficient of correlation (R) for the testing data was applied to display the best SVM model. The SVM model generated with Radial Basis Function (RBF) as the kernel function showed the best R value equal to 0.8526. MLR and ANN models had R values of 0.7630 and 0.8723, respectively. [ABSTRACT FROM AUTHOR]

Although cyclic voltammetry (CV) measurements in solution have been widely used to determine the highest occupied molecular orbital energy (EHOMO) of semiconducting organic molecules, an understanding of the experimentally observed discrepancies due to the solvent used is lacking. To explain these differences, we investigate the solvent effects on EHOMO by combining density functional theory and molecular dynamics calculations for four donor molecules with a common backbone moiety. We compare the experimental EHOMO values to the calculated values obtained from either implicit or first solvation shell theories. We find that the first solvation shell method can capture the EHOMO variation arising from the functional groups in solution, unlike the implicit method. We further applied the first solvation shell method to other semiconducting organic molecules measured in solutions for different solvents. We find that the EHOMO obtained using an implicit method is insensitive to solvent choice. The first solvation shell, however, produces EHOMO values that are sensitive to solvent choices and agrees with published experimental results. The solvent sensitivity arises from a hierarchy of three effects: (1) the solute electronic state within a surrounding dielectric continuum, (2) ambient temperature or solvent atoms changing the solute geometry, and (3) electronic interactions between the solute and solvents. The implicit method, on the other hand, only captures the effect of a dielectric environment. Our findings suggest that EHOMO obtained by CV measurements should account for the influence of solvent when the results are reported, interpreted, or compared to other molecules. [ABSTRACT FROM AUTHOR]

The excited triplet state of a molecule (T1) is one of the principal intermediate products in various photochemical processes due to its high reactivity and relatively long lifetime. The T1 quantum yield ( φ T ) is one of the most important characteristics in the study of photochemical reactions. It is of special interest to determine the φ T of various photoactive compounds (photosensitizer, PS) used in photodynamic therapy (PDT). PDT is an effective medical technique for the treatment of serious diseases, such as cancer and bacterial, fungal and viral infections. This technique is based on the introduction of a PS to a patient's organism and its further excitation by visible light, producing reactive oxygen species (ROS) via electron or energy transfer from the PS T1 state to the biological substrate or molecular oxygen. Therefore, information on the φ T value is fundamental in the search for new and effective PSs. There are various experimental methods to determine φ T values; however, these methods demonstrate a high discrepancy between φ T values. This stimulates the analysis of various factors that can affect the determined φ T . In this study, we analyze the effect of the intensity profile of the exciting laser pulse on the calculation of the φ T value obtained by the Laser Flash Photolysis technique. The φT values were determined by analyzing the variation of a sample transient absorption in the function of the exciting laser pulse intensity, in combination with the spectral and kinetic PS characteristics obtained in nonlinear optical experiments by solving the rate equations of a five-level-energy diagram. Well-studied PSs: meso-tetra(4-sulfonatophenyl) (TPPS4) porphyrins, its zinc complex (ZnTPPS4) and the zinc complex of meso-tetrakis(N-methylpyridinium-4-yl) (ZnTMPyP) were chosen as test compounds to evaluate the proposed model. The φ T values were determined through a comparison with the φ T , T M P y P = 0.82 of meso-tetrakis(N-methylpyridinium-4-yl) (TMPyP), used as a standard. The obtained results ( φ T , T P P S 4 = 0.75 ± 0.02 , φ T , Z n T M P y P = 0.90 ± 0.03) , and φ T , Z n T P P S 4 = 0.89 ± 0.03 ) are highly compatible with the medium φ T values obtained using the known methods. [ABSTRACT FROM AUTHOR]

Graphite is widely used as a solid lubricant due to its layered structure, which enables ultralow friction. However, the lubricity of graphite is affected by ambient conditions and previous studies have shown a sharp contrast between frictional behavior in vacuum or dry environments compared to humid air. Here, we studied the effect of organic gaseous species in the environment, specifically comparing the adsorption of phenol and pentanol vapor. Atomic force microscopy experiments and reactive molecular dynamics simulations showed that friction was larger with phenol than with pentanol. The simulation results were analyzed to test multiple hypotheses to explain the friction difference, and it was found that mechanically driven chemical bonding between the tip and phenol molecules plays a critical role. Bonding increases the number of phenol molecules in the contact, which increases the adhesion as well as the number of atoms in registry with the topmost graphene layer acting as a pinning site to resist sliding. The findings of this research provide insight into how the chemistry of the operating environment can affect the frictional behavior of graphite and layered materials more generally.

Titan is a key planetary body for astrobiology, with the presence of a subsurface ocean and a dense atmosphere, in which complex chemistry is known to occur. Approximately 1-Titan-year after the Cassini-Huygens mission arrived in the saturnian system, Dragonfly rotorcraft will land on Titan's surface by 2034 for an exhaustive geophysical and chemical investigation of the Shangri-La organic sand sea region. Among the four instruments onboard Dragonfly, the Dragonfly Mass Spectrometer (DraMS) is dedicated to analyze the chemical composition of surface samples and noble gases in the atmosphere. One of the DraMS analysis modes, the Gas Chromatograph-Mass Spectrometer (GC-MS), is devoted to the detection and identification of organic molecules that could be involved in the development of a prebiotic chemistry or even representative of traces of past or present life. Therefore, DraMS-GC subsystem should be optimized to detect and identify relevant organic compounds to meet this objective. This work is focused on the experimental methods employed to select the chromatographic column to be integrated in DraMS-GC, to assess the analytical performances of the column selected, and also to assess the performances of the second DraMS-GC column, which is devoted to the separation of organic enantiomers. Four different stationary phases have been tested to select the most relevant one for the separation of the targeted chemical species. The results show that the stationary phase composed of polymethyl (95%) diphenyl (5%) siloxane is the best compromise in terms of efficiency, robustness, and retention times of the molecules. The combination of the general and the chiral columns in DraMS is perfectly suited to in situ chemical analysis on Titan and for the detection of expected diverse and complex organic compounds. [ABSTRACT FROM AUTHOR]

The role of biochar–microbe interaction in plant rhizosphere mediating soil-borne disease suppression has been poorly understood for plant health in field conditions. Chinese ginseng (Panax ginseng C. A. Meyer) is widely cultivated in Alfisols across Northeast China, being often stressed severely by pathogenic diseases. In this study, the topsoil of a continuously cropped ginseng farm was amended at 20 t ha−1, respectively, with manure biochar (PB), wood biochar (WB), and maize residue biochar (MB) in comparison to conventional manure compost (MC). Post-amendment changes in edaphic properties of bulk topsoil and the rhizosphere, in root growth and quality, and disease incidence were examined with field observations and physicochemical, molecular, and biochemical assays. In the 3 years following the amendment, the increases over MC in root biomass were parallel to the overall fertility improvement, being greater with MB and WB than with PB. Differently, the survival rate of ginseng plants increased insignificantly with PB but significantly with WB (14%) and MB (21%), while ginseng root quality was unchanged with WB but improved with PB (32%) and MB (56%). For the rhizosphere at harvest following 3 years of growing, the total content of phenolic acids from root exudate decreased by 56, 35, and 45% with PB, WB, and MB, respectively, over MC. For the rhizosphere microbiome, total fungal and bacterial abundance both was unchanged under WB but significantly increased under MB (by 200 and 38%), respectively, over MC. At the phyla level, abundances of arbuscular mycorrhizal and Bryobacter as potentially beneficial microbes were elevated while those of Fusarium and Ilyonectria as potentially pathogenic microbes were reduced, with WB and MB over MC. Moreover, rhizosphere fungal network complexity was enhanced insignificantly under PB but significantly under WB moderately and MB greatly, over MC. Overall, maize biochar exerted a great impact rather on rhizosphere microbial community composition and networking of functional groups, particularly fungi, and thus plant defense than on soil fertility and root growth. [ABSTRACT FROM AUTHOR]

Arsenic is a toxic non-metallic element that is widely found in nature. In addition, arsenic and arsenic compounds are included in the list of Group I carcinogens and toxic water pollutants. Therefore, rapid and efficient methods for detecting arsenic are necessary. In the past decade, a variety of small molecule fluorescent probes have been developed, which has been widely recognized for their rapidness, efficiency, convenience and sensitivity. With the development of new nanomaterials (AuNPs, CDs and QDs), organic molecules and biomolecules, the conventional detection of arsenic species based on fluorescence spectroscopy is gradually transforming from the laboratory to the portable kit. Therefore, in view of the current research status, this review introduces the research progress of both traditional and newly developed fluorescence spectrometry based on novel materials for arsenic detection, and discusses the potential of this technology in the rapid screening and field testing of water samples contaminated with arsenic. The review also discusses the problems that still exist in this field, as well as the expectations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The presence of urea favors anion adsorption but decreases cation adsorption. • The urea as H-bond donor stabilizes the H-bonded network. • The stable H-bonded network close to the anode can accommodate anions. Capacitive deionization as a promising electrochemical technology has been tried to recover valuable nitrogen resource from urine solution. Such urine solution is usually complex in component, leading to competitive adsorption between target ions and organic molecules. To elucidate this competitive behavior at the atomic scale, we used the molecular dynamics simulation method under constant electrode potential to simulate NaCl solutions under different concentrations of urea. The presence of urea enhances the adsorption of anions at the anode but weakens the adsorption of cations at the cathode. In addition, urea molecules tend to replace water molecules near the two poles, and its electrostatic distribution characteristics cause urea molecules to adsorb parallel to the anode and perpendicular to the cathode, thus affecting the ion adsorption behavior. Furthermore, the urea molecules at the anode as H-bond donors favor the stability of the network, hence accommodating more anions, but the urea molecules with the hydrogen segment orienting to the cathode impede their H-bond donating and further push the cation adsorption layer away from the cathode. This work reveals atomistic details of the competitive adsorption between target ions and organic molecules, thereby supporting the improvement of CDI in treating complex wastewater. [ABSTRACT FROM AUTHOR]

The combination of the generical molecular maps of atom‐level properties (MOLMAPs) encoding approach and the Random Forest algorithm (RF) is applied in order to model, predict, and interpret the structural motifs responsible for a certain organic molecule's melting point (mp) profile. A high‐quality database is used for model build‐up and evaluation of predictive ability. The obtained results for the complete independent test set (R2 = 0.811, MAE = 31.99 K, RMS = 43.98 K) are comparable or better than reference works. The form of codification represents implicitly the structure of a given molecule and highlights the interactions responsible for a certain melting point profile. This generical encoding approach groups different structural motifs based on its calculated atomic‐based properties leading to good predictive ability for structurally different chemical systems not contained in the training set. [ABSTRACT FROM AUTHOR]

The Sample Analysis at Mars (SAM) suite instrument on board NASA's Curiosity rover has characterized the inorganic and organic chemical composition of seven samples from the Glen Torridon (GT) clay‐bearing unit. A variety of organic molecules were detected with SAM using pyrolysis (up to ∼850°C) and wet chemistry experiments coupled with evolved gas analysis (EGA) and gas chromatography‐mass spectrometry. SAM EGA and GCMS analyses revealed a greater diversity and abundance of sulfur‐bearing aliphatic and aromatic organic compounds in the sediments of this Gale crater unit than earlier in the mission. We also report the detection of nitrogen‐containing, oxygen‐containing, and chlorine‐containing molecules, as well as polycyclic aromatic hydrocarbons found in GT, although the sources of some of these organics may be related to the presence of chemical reagents in the SAM instrument background. However, sulfur‐bearing organics released at high temperature (≥600°C) are likely derived from Martian sources (e.g., igneous, hydrothermal, atmospheric, or biological) or exogenous sources and consistent with the presence of recalcitrant organic materials in the sample. The SAM measurements of the GT clay‐bearing unit expand the inventory of organic matter present in Gale crater and is also consistent with the hypothesis that clay minerals played an important role in the preservation of ancient refractory organic matter on Mars. These findings deepen our understanding of the past habitability and biological potential of Gale crater. Plain Language Summary: Organic molecules are essential to all life as we know it. Clay minerals are known on Earth for their high organic preservation potential and can be key indicators of past habitable environments. On Mars, the Glen Torridon (GT) region in Gale crater was first identified from orbit as a priority target for the Mars Science Laboratory mission due to its abundant clay minerals. To evaluate the organic preservation potential of this region, seven rock samples were collected and characterized using the Sample Analysis at Mars (SAM) instrument onboard the Curiosity rover. The SAM investigation indicated the presence of various organic compounds, including the first observation on Mars of some sulfur‐containing and ring‐structured organics and the highest abundance of sulfur organics observed to date. Our investigation of the sources of these organics revealed that while some of the sulfur‐bearing organics are likely Martian, a portion may also be related to the presence of chemical reagents carried in SAM, making attribution to a definitive source challenging. Nevertheless, these new SAM results confirm that ancient organic matter is preserved in the clay mineral bearing sediments of GT. Its origin—either meteoritic, abiotic or biotic—has yet to be established. Key Points: Curiosity explored the Glen Torridon region of Gale crater, which has a smectite‐rich mineralogy with high organic preservation potentialThe greatest diversity and abundance of sulfur‐bearing organics to date were detected in the solid samples by the SAM instrumentS‐bearing organics extracted ≥600°C and some aromatic compounds likely come from martian refractory organic matter [ABSTRACT FROM AUTHOR]

As a direct-bandgap semiconductor, single-layer MoS2 has gained great attention in optoelectronics, especially wearable photodetectors. However, MoS2 exhibits poor photoresponsivity on a stretchable substrate due to intrinsic low carrier density and a large number of scattering centers on polymer substrates. Few air-stable yet strong dopants on MoS2 has been reported. In addition, the roughness, hydrophobicity and susceptibility to organic solvents of polymer surface are critical roadblocks in the development of stretchable high-performance MoS2 photodetectors. Here, we realize a stretchable and stable photodetector with high photoresponsivity by combining n-type dopant ((4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl) phenyl) dimethylamine, N-DMBI) with MoS2 and assembly transfer technique. It is found electron tends to transfer from N-DMBI to MoS2 and the effect is maintained after the integrable photodetector transferred directly by elastic substrate styrene-ethylene-butylene-styrene (SEBS), even after being exposed to the air for 20 days, which benifits greatly from the encapsulation of SEBS. The increased carrier density greatly promotes carrier injection efficiency and photogenerated electron-hole separation efficiency at the metal-semiconductor interface, thus offering a significantly improved photoresponsivity in MoS2 photodetectors. Moreover, such photodetector shows great durability to stretch, which can remain functional after stretched 100 cycles within its stretch limit. Our strategy opens a new avenue to fabricate high-photoresponsivity stretchable electronics or optoelectronics of two-dimensional (2D) materials. [ABSTRACT FROM AUTHOR]

A multi-template molecularly imprinting polymer (MT-MIP) strategy has been proposed and is increasingly utilised to synthesise MIP with multiple recognition sites in a single polymer using multiple target species as templates. This approach can expand MIP applications for simultaneous recognition and extraction of more than one analyte. The advantages of MT-MIP are simultaneous analyte extraction in one process, lower solvent consumption, cost-effectiveness, and short analysis time. The use of multiple templates to prepare a MIP reduces the effort required to prepare different MIPs for different analytes separately. Although there are many studies about developing MT-MIP, there are no review articles that discuss the success rate of MT-MIP. Therefore, in this review, we summarise MT-MIP synthesis, including the polymerisation method being used, the important factors that affect the quality of MT-MIP, and MT-MIP applications. MT-MIP has great potential in chemical isolation and analysis. MT-MIP produces a product that has good sensitivity, selectivity, and reusability. Furthermore, many templates, functional monomers, and crosslinkers can be formulated as MT-MIP and have a high success rate. This is evidenced by the good values of the maximum absorption capacity (Qmax), imprinting factor (IF), and reusability. We expect that the evidence presented in this review can encourage additional research on the development and application of MT-MIP. [ABSTRACT FROM AUTHOR]

In contrast to the widely reported excited-state single proton-transfer, excited-state multiple proton transfer (ESMPT) containing two or more intra- or inter-molecular proton transfers has greatly expanded the research scope of the excited-state proton transfers. In recent decades, ESMPT-active organic molecules have attracted much attention owing to their unique photophysical properties, such as large magnitude Stokes shifts and dual emission. These photophysical properties facilitate the application of the organic molecules in organic solid-state lasers, fluorescent probes and sensors, and molecular switches. Herein, we introduce the fundamentals of the ESMPT and review the recent advances in different types of ESMPTs in organic molecules. Finally, we present our conclusions and the future development prospects of the ESMPT in organic molecules. [ABSTRACT FROM AUTHOR]

In the past decades, the invention of scanning probe microscopy (SPM) as the versatile surface-based characterization of organic molecules has triggered significant interest throughout multidisciplinary fields. In particular, the bond-resolved imaging acquired by SPM techniques has extended its fundamental function of not only unraveling the chemical structure but also allowing us to resolve the structure-property relationship. Here, we present a systematical review on the history of chemical bonds imaged by means of noncontact atomic force microscopy (nc-AFM) and bond-resolved scanning tunneling microscopy (BR-STM) techniques. We first summarize the advancement of real-space imaging of covalent bonds and the investigation of intermolecular noncovalent bonds. Beyond the bond imaging, we also highlight the applications of the bond-resolved SPM techniques such as on-surface synthesis, the determination of the reaction pathway, the identification of molecular configurations and unknown products, and the generation of artificial molecules created via tip manipulation. Lastly, we discuss the current status of SPM techniques and highlight several key technical challenges that must be solved in the coming years. In comparison to the existing reviews, this work invokes researchers from surface science, chemistry, condensed matter physics, and theoretical physics to uncover the bond-resolved SPM technique as an emerging tool in exploiting the molecule/surface system and their future applications.

The Asian tiger mosquito Aedes albopictus is well adapted to urban environments and takes advantage of the artificial containers that proliferate in anthropized landscapes. Little is known about the physicochemical, pollutant, and microbiota compositions of Ae. albopictus-colonized aquatic habitats and whether these properties differ with noncolonized habitats. We specifically addressed this question in French community gardens by investigating whether pollution gradients (characterized either by water physicochemical properties combined with pollution variables or by the presence of organic molecules in water) influence water microbial composition and then the presence/absence of Ae. albopictus mosquitoes. Interestingly, we showed that the physicochemical and microbial compositions of noncolonized and colonized waters did not significantly differ, with the exception of N2O and CH4 concentrations, which were higher in noncolonized water samples. Moreover, the microbial composition of larval habitats covaried differentially along the pollution gradients according to colonization status. This study opens new avenues on the impact of pollution on mosquito habitats in urban areas and raises questions on the influence of biotic and abiotic interactions on adult life-history traits and their ability to transmit pathogens to humans., (© The Author(s) 2024. Published by Oxford University Press on behalf of FEMS.)

Due to their excellent thermal stability and suitable bandgap, all‐inorganic CsPbI x Br3−x perovskite solar cells (PSCs) have attracted extensive attention in the photovoltaic field. However, iodine vacancies and undercoordinated Pb2+ lead to serious nonradiative recombination losses on the surface of CsPbI x Br3−x perovskite film, resulting in lower open‐circuit voltage. At the same time, the cubic phase (α phase) tends to transform into the yellow phase (δ phase) with nonphotoactive in an environment of higher humidity and lower temperature, which limits its further commercial development. In order to solve the above problems, a lot of research work is focused on interface modification and precursors doping to improve the crystallinity, surface hydrophobicity, and phase stability of perovskite films. In this review, the application of organic molecules in all‐inorganic CsPbI x Br3−x PSCs and prospected the research direction in the future to further improve the performance and stability are summarized.

Merging the light- harvesting and emitting capability of inorganic materials with the versatile excited-state properties of organic molecules leveraging triplet energy transfer (TET) has recently become an important design strategy for light-driven applications ranging from energy conversion, biomedicine, to photoredox catalysis, and understanding the rules that govern such phenomena is essential. Recent years have witnessed some breakthroughs of TET as well as significant advances for regulating this photochemical process, but it still needs more integrated research at the center. In particular, efficient TET between semiconductor nanocrystals (or quantum dots) and organic molecules, which combines nanoscale size effect of the former and molecular versatility of the latter, has been demonstrated as a promising enabler for breaking the Shockley-Queisser limit in solar energy conversion, controlling photon emission, and driving photochemical reactions in the years to come. Here we review the fundamentals of TET mechanism and some of its emerging applications, with special focus on recent progress towards the understanding and application of TET in nanocrystal-molecule hybrids and highlight some challenges for the field. Work is currently aimed at providing insights in controlling TET dynamics with a view to making the process as efficient as possible according to expected designs.

Photovoltaics has become one of the emerging alternatives to progressively supply/replace conventional energy sources, considering the potential exploitation of solar energy. Depending on the nature of the light harvester to influence on its light-absorption capability and the facility to produce electricity, different generations of solar devices have been fabricated. Early studies of organic molecules (dye sensitizers) with good absorption coefficients, going through metal chalcogenides and, lastly, the timely emergence of halide perovskites, have promoted the development of novel and low-cost solar cells with promising photoconversion efficiency (PCE), close to the well-established Si-based devices. However, main drawbacks such as the degradation/photocorrosion of the active layer, the existence of intrinsic defect sites, and the inherent toxicity of the material due to the presence of some harmful elements have blocked the future commercialization of the above kind of solar cells. In this review, we highlight the current progress in achieving efficient photomaterials for organic, chalcogenides and halide perovskites-based solar cells with the purpose of achieving high PCE values, some of which are breakthroughs in this research topic, and the diverse approaches used to extend the stability of the active layer and improve the performance of the solar devices.

Over the past few decades, molecular self-assembly has witnessed tremendous progress in a variety of biosensing and biomedical applications. In particular, self-assembled nanostructures of small organic molecules and peptides with intriguing characteristics (e.g., structure tailoring, facile processability, and excellent biocompatibility) have shown outstanding potential in the development of various biosensors. In this review, we introduced the unique properties of self-assembled nanostructures with small organic molecules and peptides for biosensing applications. We first discussed the applications of such nanostructures in electrochemical biosensors as electrode supports for enzymes and cells and as signal labels with a large number of electroactive units for signal amplification. Secondly, the utilization of fluorescent nanomaterials by self-assembled dyes or peptides was introduced. Thereinto, typical examples based on target-responsive aggregation-induced emission and decomposition-induced fluorescent enhancement were discussed. Finally, the applications of self-assembled nanomaterials in the colorimetric assays were summarized. We also briefly addressed the challenges and future prospects of biosensors based on self-assembled nanostructures.

We present a simple method for modification of 2D materials by drop-casting of the organic molecule in solution on the 2D material under ambient conditions. Specifically, we investigated the adsorption of 6-(4,5-Dihydro-1H-imidazol-3-ium-2-yl)-2-(naphthalene-2-yl)benzothiazole methanesulfonate (L63MS) organic molecule on 2D MoS2. To better understand the effect of the organic molecule on the 2D material, we also investigated the impact of solvents alone on the materials’ properties. The MoS2 samples were synthesized using ambient pressure chemical vapor deposition. Atomic force microscopy, Raman spectroscopy, photoluminescence spectroscopy and optical microscopy were used to characterize the samples. The measurements were performed after synthesis, after the drop-casting of solvents and after the drop-casting of organic molecule solutions. Our results indicate that the used organic molecule effectively adsorbs on and prompts discernible changes in the (opto)electronic properties of the 2D material. These changes encompass variations in the Raman spectra shape, alterations in the photoluminescence (PL) signal characteristics and modifications in excitonic properties. Such alterations can be linked to various phenomena including doping, bandgap modifications, introduction or healing of defects and that the solvent plays a crucial role in the process. Our study provides insights into the modification of 2D materials under ambient conditions and highlights the importance of solvent selection in the process.

The high defect density on the surface of AlGaN material with high Al composition limits its application in the field of solar-blind ultraviolet (UV) detection. In this work, a surface modification method for AlGaN has been proposed to enhance the performance of AlGaN metal–semiconductor–metal (MSM) solar-blind UV photodetectors (PDs). The 5,10,15,20-T(4-OH P)P (C44H30N4O4) organic molecules are chemically adsorbed on the surface of high-Al-content Al0.6Ga0.4N MSM PD, which can reduce the interface potential caused by material defects and increase the photogenerated carriers of the device. Compared with the control unmodified PD, the C44H30N4O4 modification method significantly increases the photocurrent and responsivity of the PD, which is beneficial to improve the optoelectronic performances of III-nitride-based PDs. [ABSTRACT FROM AUTHOR]

The words organic and synthesis originate with Aristotle (meaning 'instrumental' and 'put together', respectively) but had different meanings over time. The iatrochemists prepared numerous pharmaceutical remedies in the 1600s but had no concept of organic chemistry. Buffon, Bergman and Gren defined organic bodies as living things in the 1700s, but discrete organic compounds remained unknown. In the late 1700s and early 1800s, organic natural products were isolated by Scheele, and Chevreuil separated carboxylic acids from saponification of fats. Organic chemistry had started. Lavoisier invented and Berzelius improved combustion analysis for organic characterization. Descartes' dictum that synthesis is required to prove an analysis was enacted by Bergman and others. The concept of organic chemistry changed radically when Wöhler and Kolbe prepared organic compounds from the elements. Berthelot's syntheses of non‐natural fats in 1853 started modern synthetic organic chemistry as the chemistry of carbon compounds, regardless of whether occurring in Nature or not. [ABSTRACT FROM AUTHOR]

Molecular doping is an excellent instrument to modify the electronic properties of two−dimensional materials. In our work, the structure and electronic properties of the adsorption systems of g−ZnO adsorbed by organic molecules (including Tetracyanoethylene (TCNE), Tetracyanoquinodimethane (TCNQ), and Tetrahydrofulvalene (TTF)) were investigated computationally using Density Functional Theory (DFT). The results showed that the TCNE and TCNQ, as electron receptors, doped the LUMO energy level above the valence band maximum (VBM) of the g−ZnO band structure, demonstrating effective p−type doping. The n−type doping of g−ZnO was obtained that the TTF molecules, as electron donors, doped the HOMO energy level below the conduction band minimum (CBM) of the band structure for g−ZnO. In addition, the TCNE, TCNQ, and TTF breathed additional holes or electrons into the monolayer g−ZnO, creating surface dipole moments between the g−ZnO and organic molecules, which caused work function to be adjustable, ranging from 3.871 eV to 5.260 eV. Our results prove that organic molecular doping was instrumental in improving the performance of g−ZnO−based nano−electronic devices, providing theoretical support for the fabrication of p−doping or n−doping nano−semiconductor components. The tunable range of field emission capability of g−ZnO−based electronic devices was also extended. [ABSTRACT FROM AUTHOR]

Molecular electronic devices based on few and single-molecules have the advantage that the electronic signature of the device is directly dependent on the electronic structure of the molecules as well as of the electrode-molecule junction. In this work, we use a two-step approach to synthesise functionalized nanomolecular electronic devices (nanoMoED). In first step we apply an organic solvent-based gold nanoparticle (AuNP) synthesis method to form either a 1-dodecanethiol or a mixed 1-dodecanethiol/ ω -tetraphenyl ether substituted 1-dodecanethiol ligand shell. The functionalization of these AuNPs is tuned in a second step by a ligand functionalization process where biphenyldithiol (BPDT) molecules are introduced as bridging ligands into the shell of the AuNPs. From subsequent structural analysis and electrical measurements, we could observe a successful molecular functionalization in nanoMoED devices as well as we could deduce that differences in electrical properties between two different device types are related to the differences in the molecular functionalization process for the two different AuNPs synthesized in first step. The same devices yielded successful NO2 gas sensing. This opens the pathway for a simplified synthesis/fabrication of molecular electronic devices with application potential. [ABSTRACT FROM AUTHOR]