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A simple and efficient cross-coupling of aryl halides with different alkyl disulfides under mild conditions was developed. This C–S bond formation method was carried out in the absence of transition-metal and external photosensitizer under air. Excellent yields were obtained with a broad substrate scope under mild conditions, tolerating various functional groups.

Alcohols are versatile structural motifs of pharmaceuticals, agrochemicals and fine chemicals. With respect to green chemistry, the development of more sustainable and cost-efficient processes for converting ketones/aldehydes to alcohols is highly desired. Herein, a direct light-driven strategy for reducing ketones/aldehydes to alcohols using isopropanol as the reducing agent and solvent, in the presence of t-BuOLi, under an air atmosphere at room temperature is developed. This operationally simple light-promoted Meerwein–Ponndorf–Verley (MPV) type reduction can be used to produce various benzylic alcohol derivatives as well as applied to bioactive molecules and PEEK model compounds, demonstrating its application potential.

The poor visible light utilization and inferior charge separation efficiency of the TiO2 photoanode restrict its photoelectrochemical (PEC) activity for water oxidation. Therefore, herein, we report a dual-regulation charge separation strategy with a synergistic effect between a 1D/0D heterostructure and inserted ferroelectric layer in a TiO2/SrTiO3/CdS (nanorod/ferroelectric/quantum dot) composite photoanode to boost the PEC performance of TiO2. The ferroelectric SrTiO3 (STO) nanolayer exhibited a polar charge-induced electric field from the STO/CdS interface toward the TiO2/STO interface, resulting from strong and endurable spontaneous polarization. The polar charge-induced electric field, assisted by the TiO2/STO/CdS ternary heterojunction with cascade energy band alignment, simultaneously endowed persistent and rapid charge separation in the bulk and at TiO2/STO/CdS interfaces, which enhanced the charge separation efficiency by 148% compared to that of pure TiO2. Meanwhile, the obtained TiO2/STO/CdS photoanode allowed the integration of boosted charge carrier density, easier hole extraction and increased active sites from the outer CdS 0D quantum dots. Consequently, the TiO2/STO/CdS photoanode presented a prominently improved photocurrent of 1.85 mA cm−2 (at 1.23 V vs. RHE), which was 7.4 times that of TiO2. Thus, this integrated regulation strategy may open an avenue to pursue enhanced charge separation assisted by broadened light absorption for converting solar energy into fuel.

A method of constructing BiFeO3/Cu2O heterojunction on the surface of BiFeO3 is reported by using sol–gel and magnetron sputtering. The photocurrent density of BiFeO3 with heterostructure is 6.8 times the original BiFeO3. The photoelectrochemical performance improvement of BiFeO3/Cu2O was due to the effective construction of heterojunctions, which improves the light absorption capacity, reduces the resistance in charge transfer and also effectively accelerates the separation and collection of photogenerated electron–hole pairs. This work provides a promising strategy to develop high-efficiency PEC electrodes, and has potential to be applied in the visible-light water splitting area.

Recently, all-inorganic cesium lead halide perovskite CsPbX3 (X = Cl, Br, and I) colloidal nanoparticles (NPs) have attracted tremendous attention owing to their potential applications in light-emi...

Using an advanced cryogenic thermal desorption spectroscopy (ACTDS) apparatus together with the temperature-programmed desorption (TPD) methodology, three MOF materials with different textural characteristics were examined for the separation of an equimolar H2/D2 mixture through quantum sieving. Finally, a universal fundamental correlation between the separation performance of (equilibrium) quantum sieving and pore size with temperature is established, which, for specific pore apertures, results in a subordinate local optimal operational temperature (LOOT) phenomenon that is dominant at local temperatures; the influence of the textural characteristics of different materials on this correlation is also illustrated in detail and clearly demonstrates that a good material for efficient H2/D2 quantum sieving should possess homogeneous hydrophilic pores with only one strong adsorption site. These results will exert great directive significance on defining the optimal operational conditions and suitable materials for more effective H2/D2 quantum sieving performance in a practical way.

A palladium-catalyzed hydroalkylation reaction of methylenecyclopropanes via highly selective C–C σ-bond scission was achieved under mild conditions, in which simple hydrazones served as carbanion equivalents. This method featured good functional group compatibility, affording high yields of C-alkylated terminal alkenes., A palladium-catalyzed hydroalkylation of methylenecyclopropanes via selective C–C σ-bond scission was achieved, in which simple hydrazones served as carbanion equivalents. This method affords high yields of C-alkylated terminal alkenes with good functional group compatibility.

Aldehydes and ketones are widely found in biomass resources and play important roles in organic synthesis. However, the direct deoxygenative coupling of aldehydes or ketones to construct C(sp3)−C(sp3) bond remains a scientific challenge. Here we report a nickel−catalyzed reductive homo-coupling of moisture- and air-stable hydrazones generated in-situ from naturally abundant aldehydes and ketones to construct challenging C(sp3)−C(sp3) bond. This transformation has great functional group compatibility and can suit a broad substrate scope with innocuous H2O, N2 and H2 as the by-products. Furthermore, the application in several biological molecules and the transformation of PEEK model demonstrate the generality, practicability, and applicability of this novel methodology.

Great efforts have been paid to enhance the photoelectrochemical performances of LaFeO3. However, there have rarely been reported about modifying of LaFeO3 with transitional metal borides for enhanced photoelectrochemical activities. Herein, we prepared LFO/Ni–B composite electrodes by immersing LFO into the prepared electroless plating solution. The optimized LFO/Ni–B composite exhibits a 373% improvement of the photocurrent density and exhibits an anodic shift of onset potential. Systematic studies reveal that the improvement of PEC activity should be attributed to enhanced electrochemically active surface area and electrocatalytic properties, reduced resistance of the PEC system, and a more pronounced downward band bending at the photoelectrode/electrolyte interface.

Identifying effective means to improve the charge separation performance assisted by adequate surface reaction represents a significant challenge for developing a highly efficient TiO2 photoanode. Here we report a structural synergistic strategy between a close contact heterojunction and a surface oxygen vacancy to significantly boost the charge separation efficiency and charge injection efficiency of TiO2 nanowires (NWs) in PEC water splitting. To accomplish this task, a TiO2/SrTiO3 (TiO2/STO) heterojunction was first constructed by in situ conversion, resulting in close contact between interface, promoting separation of the photoinduced charge carriers, which increased charge separation efficiency by 107% compared to TiO2. After the amorphous layer was established on the surface of the SrTiO3 coating, the resulting TiO2/SrTiO3/r-SrTiO3 (TiO2/STO/r-STO) improved the light absorption property of the photoelectrodes and boosted the ability to adsorb the reactant hydroxide ions, resulting in charge injection efficiency improvement by 67.3% compared with pure TiO2. This complementary modification for enhancing charge separation and boosting the surface reaction demonstrates a significant capacity to improve the photoelectrochemical (PEC) performance of one photoanode, which could be instructive for other fields including photocatalysis and PEC carbon dioxide reduction.

Construction of plasmon-based nanostructures is an effective way to enhance the photocatalytic activities of semiconductor photocatalysts for water-splitting. However, the synergistic effect of plasmon-related hot electrons and holes for water splitting in the plasmon-hybrid photocatalyst is rarely considered. Herein, we construct a plasmon-based Au/LaFeO3 composite photocatalyst to investigate the complex roles of hot electrons and holes for solar water splitting. Benefiting from the formation of Schottky junction and surface plasmon resonance effect of the Au nanoparticles, the synthesized photocatalyst exhibits an excellent photocatalytic activity for each half-reaction of water splitting, and the rates for H2 and O2 generation are obtained as high as 202 μmol g−1 h−1 and 23 μmol g−1 h−1, respectively. Moreover, an in-depth investigation reveals that the improved hydrogen evolution is caused by the hot electron injection from Au to LaFeO3, and the hot holes in Au induced by the separation of hot charges can initiate the water oxidation directly on the surface of gold. Thus, this work provides a new insight into the synergistic effect of plasmon-related hot electrons and holes for boosting the photocatalytic reactions.

Graphene has aroused continual and tremendous interest in gas sensing applications because of its unique properties. However, the graphene-based sensors still meet limitations such as inconvenient device fabrication, sustained power supply, specific measuring equipment, etc. Here, we find that fluorinated graphene (FG) shows an obvious color change (from white to dark yellow) in the presence of NH3 which can be observed directly by the naked eye. PL measurement shows that the sensitivity of color change can reach a high value of ca. 4.05% ppm−1. The density functional theory calculations reveal that the F atoms on FG increase the adsorption ability and charge transfer of NH3 molecules, resulting in the efficient color change. This work develops a naked-eye sensor which needs no device fabrication, power supply or measuring equipment, thus, can be potentially used to manufacture a cheap, sensitive and miniaturized NH3 sensor.

Fluorination is a feasible method to modify the properties of graphene. However, the fluorination methods still meet different limitations such as inconvenient, low-yield, high-cost, etc. Here, a room-temperature method at ambient conditions was presented to synthesize fluorinated graphene oxide (FGO). The obtained FGO had the F content of ca. 28.6 at%. The mechanism of the reaction at ambient conditions was discussed by theoretical calculations, which showed that the oxygen groups facilitated to generate stable C F bonds by overcoming a low reaction barrier. This work provides an easy synthesis of FGO, broadening the applications of functionalized graphene, for example, increasing the magnetic inducing efficiency to ca. 1.03 × 10−2 μB/F.

An umpolung strategy for the cross-coupling of polyfluoroarenes with various substituted hydrazones to construct C(sp2)-C(sp3) bonds is developed. In this strategy, the C-F bond of polyfluoroarenes is cleaved and coupled with moisture- and air-stable hydrazones under mild conditions with good to excellent yields. This method provides a useful tool for synthesizing polyfluorinated pharmaceuticals and functional materials.

Fluorination and N-doping are two feasible routes to modify the properties of graphene. However, it’s difficult to modulate the F-distribution and N-configuration. Here, we found that by the mutual influence between F and N atoms, F-distribution and N-configuration can be facilely modulated. In brief, by annealing F and N dual-functionalized graphene, (i) F-distribution tended to be discrete, and (ii) graphitic N-configuration was progressively converted to pyridinic, and pyridinic to pyrrolic N-configuration. Theoretical calculations indicated that the modulation of F-distribution was due to the adsorptive ability of N atoms, and N-configuration was modulated because F decreased the stability of N-configuration. Furthermore, we found that the mutual modulation of F-distribution and N-configuration could reinforce the radiative recombination of electron-hole pairs, which increased the photoluminescence intensity to 320.69%. This work provides a facile strategy to modulate the distribution and configuration of heteroatoms, broadening the potential applications of dual-functionalized graphene.

Due to an appropriate band gap of 2.07 eV, perovskite LaFeO3 (LFO) is an alternative candidate for high-efficiency photoelectrochemical (PEC) systems. However, the photocurrent of the LFO photocathode is too low to be practical. Herein, we prepared a LFO film with high crystal quality by inserting an Au thin layer between LFO and FTO in the LFO/FTO photocathode. Accordingly, an effective improvement PEC performance could be obtained and the photocurrent density of the FTO/Au/LFO electrode was increased to −19.60 μA cm−2 at 0.6 V vs. RHE, which is 4.1 times higher than that of pristine FTO/LFO electrode. Based on the experimental and theoretical analysis, the enhancement of the photocurrent was attributed to the strong light harvesting, enhanced charge separation, and increased charge-collection efficiency of the Au/LFO structure. This work provides a promising strategy to develop high-efficiency PEC electrodes, and has potential to be applied in the visible-light water splitting area.

Carbazole is an essential building block in various pharmaceuticals, agrochemicals, natural products, and materials. For future sustainability, it is highly desirable to synthesize carbazole derivatives directly from renewable resources or cheap raw materials. Phenolic compounds are a class of degradation products of lignin. On the other hand, ammonia is a very cheap industrial inorganic chemical. Herein, an efficient dearomatization-rearomatization strategy has been developed to directly cross-couple 2,2'-biphenols with ammonia by dual C(Ar)-OH bond cleavages. This strategy provides a greener pathway to synthesize valuable carbazole derivatives from phenols.

Etalon features in infrared spectra of stratified samples, their influence on the interpretation, and methods to circumvent their presence in infrared spectra have been in discussion for decades. This paper focuses on the application of a method originally developed to remove interference fringes in the mid-infrared spectra for far-infrared Fourier transform spectroscopy on thin polymer films. We show that the total transmittance reflectance technique, commonly used for mid-infrared, also works successfully in the far-infrared spectral range where other approaches fail. Experimental spectra obtained by such technique are supported by model calculations and reveal the possibility and limits to obtain almost undisturbed far-infrared spectra which are suitable to determine low-energy vibrations of ionomer salts under certain sample conditions.

Plasma ethanol precipitation process is an important step in the biopharmacy production process, and near infrared spectroscopy (NIRS) is an effective process analytical technology (PAT) tool in detecting the key quality attribute: the total protein (TP) content. But establishing a robust model is pretty complex. The aim of this study was to explore the calibration transfer strategy between master and slave spectrometers with the biopharmacy. Firstly, 8 batches of ethanol precipitation process were experimented. The changing spectra were collected by two spectrometers, reference values were measured by biuret method. Then, calibration transfer based on the PRS algorithm was carried out. Finally, before establishment of the optimal TP content partial least squares regression (PLSR) model of calibration transfer, rank sample set partitioning based on joint x-y distance (Rank-SPXY) and spectral pretreatment methods were selected after comparison. The determination coefficients of prediction (Rp2) and root mean squares error of prediction (RMSEP) were 0.934 and 0.8395 g/L, respectively. The results showed that Rank-SPXY-PRS was an effective calibration transfer strategy with different NIRS spectrometers. To some extent, the predictive capability of PLSR model was improved after calibration transfer, and it could provide reference for the further research in biopharmacy production process.

The conversion of renewable resources and inexpensive inorganic chemicals directly into higher value-added organic chemicals is becoming more and more important for our society’s future sustainable development. Lignin, being the second most abundant organic carbon renewable resource on Earth, has been treated as waste in the pulp and paper industry. The 4-O-5 linkage diaryl ether bond is the strongest among the three types of ether linkages in lignins. Selective cleavage of this linkage can potentially generate smaller processable bio-based aromatic polymeric materials and compounds. Furthermore, there has been a long synthetic interest in coupling reactions with aryl ethers via C(Ar)–O bond cleavage, for example, for polyphenylene oxide (PPO) waste recycling. On the other hand, ammonia is a very inexpensive industrial inorganic chemical. Herein, we report a direct conversion of diaryl ethers and ammonia into aniline derivatives and arenes, providing a model for selective lignin 4-O-5 linkage modification...

The composition of nanoparticles (NPs) and graphene has aroused tremendous attention because it can synergistically combine the advantages of NPs and graphene. However, manipulating the distribution of NPs and identifying the effect of the distribution of NPs on the properties of the composites remain challenges. Here, we used graphene oxide (GO) of different oxidation degrees as the platform to prepare the Mn3O4/reduce GO composites. We found that the distribution of Mn3O4 NPs could be manipulated by adjusting the oxygen content of GO. Then we investigated the effect of Mn3O4 distribution on the capacitive and magnetic properties of the composites. The results showed that the distribution of Mn3O4 NPs could change the active sites, charge transfer, uncompensated spins, and spin coupling of the composites, resulting in the distribution-dependent capacitive and magnetic properties. Especially, with discrete Mn3O4 distribution, the composites exhibited the high specific capacitance of 1626.0 F g−1 and mass magnetization of ca. 85.3 emu g−1 normalized to the portion of Mn3O4. This work will help in understanding the interaction of NPs and graphene for fundamental research, and push the way for potential capacitive and magnetic applications of graphene-based composites.

Lignin is the second most abundant organic matter on Earth, and is an underutilized renewable source for valuable aromatic chemicals. For future sustainable production of aromatic compounds, it is highly desirable to convert lignin into value-added platform chemicals instead of using fossil-based resources. Lignins are aromatic polymers linked by three types of ether bonds (α-O-4, β-O-4, and 4-O-5 linkages) and other C-C bonds. Among the ether bonds, the bond dissociation energy of the 4-O-5 linkage is the highest and the most challenging to cleave. To date, 4-O-5 ether linkage model compounds have been cleaved to obtain phenol, cyclohexane, cyclohexanone, and cyclohexanol. The first example of direct formal cross-coupling of diaryl ether 4-O-5 linkage models with amines is reported, in which dual C(Ar)-O bond cleavages form valuable nitrogen-containing derivatives.

An ultramicroporous MOF material, {[Fe(OH)(H2bta)](H2O)}n, was diligently selected for the experimental investigations of ultralow-temperature separation of H2/D2 through quantum sieving. With an extreme two-dimensional confinement experienced by hydrogen molecules, an extraordinary separation factor as high as 41.4 ± 0.4 at 20 K was for the first time obtained from experiment.

A transition-metal-free synthetic strategy has been developed for the synthesis of N-aryl amides. The present amination reaction of aryltriazenes with acetonitrile was carried out with acetonitrile as nitrogen donor, stable aryltriazenes as aryl precursors by the cleavage of C N bond, water as oxygen source, and Bronsted acidic ionic liquids (BAILs) as potential promoter under ambient conditions. Remarkably, the practicality of this method was further proved through the reusability of the promoter BAILs. The environmentally benign nature, stable and readily available starting materials make the protocol more attractive for preparing N-aryl amides than traditional methods.

Efficient extraction of photogenerated charge carriers is of significance for acquiring a high efficiency for perovskite solar cells. In this paper, a systematic strategy for effectively engineering the charge extraction in inverted structured perovskite solar cells based on methylammonium lead halide perovskite (CH3NH3PbI3−xClx) is presented. Intentionally doping the chlorine element into the perovskite structure is helpful for obtaining a high open circuit voltage. The engineering is carried out by modifying the aluminium cathode with zirconium acetylacetonate, doping the hole transport layer of nickel oxide (NiOx) with copper and using an advanced fluorine doped tin oxide (FTO) substrate. This improves the bandgap alignment of the whole device, and thus, is of great benefit for extracting the charge carriers by promoting the transport rate and reducing the trap states. Consequently, an optimized power conversion efficiency of 20.5% is realized. Insights into how to extract charge carriers efficiently with a minimum energy loss are discussed.

We report the first Bronsted acidic ionic liquid (IL) promoted reaction of 5-pyrazolones with aryltriazenes to prepare arylazopyrazolones. The reaction was carried out with the aryltriazenes as diazotizing agents, water as the solvent, and the ionic liquid as the promoter at room temperature under air and metal-free conditions. The desired products were obtained in good to excellent yields. Notably, a gram-scale experiment and a late-stage diazenylation reaction of a pharmaceutical derivative also furnished the desired products under mild conditions.

P-type Cu 2 O has long been regarded as an advantageous material in photoelectrochemistry, owing to the suitable band gap structure and cost-effective production. However, such promising material is suffering from corrosion in aqueous electrolytes. To address this issue and attain a high photoelectrochemical performance, protective oxide layers and expensive catalysts have to be adopted. The complicacy of such additional procedures, however, limits the further applications. Instead of utilizing surface protecting oxide layers and expensive catalysts, herein, we report that the surface treatment of Cu 2 O photocathodes using trisodium citrate (TSC) could also greatly enhance the photoelectrochemical performance. In comparison with the electrode without TSC, the photocathode of FTO/Au/Cu 2 O/TSC/TiO 2 /Pt presents a pronounced increment in photocurrent with a factor of about 2. Therefore, this paper provides a novel but convenient methodology to optimize the performance of solar energy conversion systems employing p-type Cu 2 O by modifying the surface with functional molecules.

To pursue high photocatalytic activity in visible-light region, the Fe(III) modified BiOCl ultrathin nanosheet (Fe(III)@BOC NS) has been firstly synthesized via a facile solvothermal approach. The morphological and compositional characterizations reveal that the thickness of the as-prepared Fe(III)@BOC NS is less than 5 atomic layer with the exposure of active [001] facets. And the Fe(III) doping and surface grafting result in a 0.58 eV down-shift of the BiOCl conduction band minimum extending the light absorption from ultraviolet light to visible light region, as well as a promoted interfacial charge transfer upon visible light irradiation. Meanwhile, the Fe(III) modification introduces unique active sites on the surface of ultrathin nanosheet facilitating the surface reaction. Moreover, both of the appropriate self-induced electric field of [001] facets, and the shortened charge carrier diffusion length of ultrathin nanosheet enhance the separation and transfer efficiency of charge carriers. Therefore, by taking those advantages, we experimentally demonstrate that the Fe(III)@BOC NS is a high-efficiency visible-light photocatalyst for both of environment remediation and water splitting.

We herein report a simple and clean photo-induced metal-free reduction of C-X bond under an atmosphere of air at room temperature. Isopropanol is used as both the reducing reagent and solvent. Various functional groups (acids, esters, alcohols, anilines, phenols, indoles, pyridines, cyano and trifluoromethyl groups) and other heterocyclic compounds are tolerated. Different organic halides (including C-I, C-Br and C-Cl bonds) can be dehalogenated with moderate to excellent yields. Polyhalides are also reduced chemoselectively and efficiently. DFT calculation suggests a six-membered ring transition state via C-XH-O hydrogen bonding to decrease the activation energy.

The ultra-low loading amount of Pt nanoparticles on three-dimensional bacterial cellulose derived carbon nanofibers (BCF) was achieved by using a modified atomic layer deposition (ALD) process for hydrogen evolution reaction (HER). The only 5 cycles of ALD led to a high dispersion of Pt nanoparticles on BCF surfaces with an average size of 2 nm, possessing an as low as 0.87 wt% of mass loading. The HER catalytic performance revealed that the as-prepared Pt/BCF have good catalytic activity and stability. The present work provides a general strategy for minimizing the demand of precious-metal catalysts while maintaining their high catalytic efficiency.

To fully utilize the multiple exciton generation effects in quantum dots and improve the overall efficiency of the corresponding photovoltaic devices, nanostructuralizing the electron conducting layer turns out to be a feasible strategy. Herein, PbS quantum dot solar cells were fabricated on the basis of morphologically optimized TiO2 nanorod arrays. By inserting a thin layer of CdSe quantum dots into the interface of TiO2 and PbS, a dramatic enhancement in the power conversion efficiency from 4.2% to 5.2% was realized and the resulting efficiency is one of the highest values for quantum dot solar cells based on nanostructuralized buffer layers. The constructed double heterojunction with a cascade type-II energy level alignment is beneficial for promoting photogenerated charge separation and reducing charge recombination, thereby responsible for the performance improvement, as revealed by steady-state analyses as well as ultra-fast photoluminescence and photovoltage decays. Thus this paper provides a good buffer layer to the community of quantum dot solar cells.

To date, technical development has boosted the efficiencies of energy converting/storing devices with conventional planar architectures to be close to the corresponding theoretical values, which are hard to be further improved without reforming the device structures. Alternatively, ordered nanostructure arrays have recently emerged as efficacious scaffolds to construct devices for converting or storing energy more efficiently. To meet the global energy requirements for producing energy renewably and unitizing energy portably, herein we provide a comprehensive summarization on ordered nanostructure arrays for energy applications. This review starts with a brief introduction of techniques for realizing ordered nanostructure arrays and then recent progress on energy-related devices equipped with such advanced architectures will be reviewed. Particular emphasis will be placed on how to develop efficient devices via theoretical simulation and structural optimization.

Unlike conventional investigations that focus on the manipulation of optical absorption band edge for a single componential material through quantum confinement effects, in this paper, we study the optical absorption properties of well-ordered ZnO/ZnS core/shell nanotube arrays. Our data point out that the profile of the absorbance spectrum of ZnO/ZnS nanotube arrays is determined by the two components and geometrical parameters of the nanostructure arrays. We find that both of the ZnO and ZnS show a decrease in the optical band gap with the increase in ZnS thickness and the diameter of the nanotube arrays, which is interestingly out of explanation from the material aspect. The subsequent finite-difference-time-domain simulations support such observations and illustrate that the geometrical and periodical parameters could also impact the optical absorption of the core/shell nanostructure arrays, even without concerning the quantum effects.

In view of the disadvantages of the conventional photocathodic materials, we focus on exploiting new candidates for a high-efficiency photoelectrochemical (PEC) system. Herein, we report on the fabrication of CuBi2O4 (CBO) films on FTO (fluorine doped tin oxide) and FTO/Au substrates, respectively, through the electrochemical deposition approach. It was observed that the presence of a Au thin layer could help to improve the crystal quality of the grown CBO films, promote the separation of photo-generated charges in the corresponding material and reduce the resistance of the system. In comparison with the FTO/CBO, the FTO/Au/CBO photocathode presents a remarkable improvement in the photocurrent, from −0.23 mA cm−2 to −0.50 mA cm−2 at 0.1 V vs. RHE. After optimizing the PEC system by depositing Pt nanoparticles on the CBO films, the plateau photocurrent was further amplified to −1.24 mA cm−2. These data indicate an attractive p-type material in photoelectrochemistry, without concern for the corrosion problem in aqueous electrolytes.

Lead halide perovskites have attracted tremendous attention recently due to their great success in the fields of photovoltaic technologies and light-emitting devices. In this work, the excitonic photoluminescence (PL) properties of all-inorganic perovskite CsPbBr3 were investigated in detail via temperature-dependent PL and Raman spectroscopy in the range of 87 K–297 K, benefiting from our recent work on solution growth of high-quality CsPbBr3 single crystals. The exciton binding energy was extracted as 37 ± 2.7 meV from temperature-dependent PL emission intensity. Furthermore, the PL emission peak energy showed complicated behaviors compared to common semiconductors. With the increase of temperature, the PL emission spectrum blueshifted below 223 K, while it was redshifted in the range of 223 K–293 K. Theoretical research indicated that the thermal expansion governs the energy bandgap evolution of CsPbBr3 below 223 K, while for higher temperatures, the contribution of electron-phonon interaction became dominant. Meanwhile, the broadening of the PL emission spectrum was mainly attributed to the exciton-longitudinal optical phonon scattering. Our results may contribute to a better understanding of the luminescence behaviors in all-inorganic perovskite CsPbBr3-based light-emitting devices in the future.

1D ZnO nanostructures have been widely explored due to their potential applications in ultraviolet (UV) region photodetectors because of their unique structural and optoelectronic properties. However, a large number of surface defect states leading to a noticeable dark current hinders their practical applications in UV photodetection. In this work, we have shown improved ZnO/Al2O3 core-shell microrod photodetectors, whose performance is significantly enhanced by defect passivation and the introduction of trap states by atomic layer deposition grown thin amorphous Al2O3 shell layer, as evidenced by steady-state and transient photoluminescence investigations. The photodetectors demonstrated suppressed dark current and increased photocurrent after capping the Al2O3 layer. Specifically, the ZnO/Al2O3 core-shell microrod photodetector exhibited a photoresponsivity as high as 0.019 A/(W cm-2) with the dark current as low as ∼1 × 10-11 A, and a high I light/I dark ratio of ∼104 under relatively weak light illumination (∼10 μW cm-2). The results presented in this work provide valuable pathways to boost the performance of 1D ZnO microrod-based photodetectors for future practical applications.

Separation of hydrogen isotopes is of great importance to produce highly pure hydrogen isotopes for numerous applications, which is however very difficult because of their almost identical thermodynamic properties. Adsorptive separation is considered as a simple, highly efficient, and cost-effective technique compared to the traditional methods, where the key is the suitable adsorbent. Herein, SIFSIX-3-Zn was screened out from the reported metal–organic frameworks (MOFs), exhibiting high selectivities for a D2/H2 mixture by quantum sieving effect. Advanced cryogenic thermal desorption spectroscopy confirms the calculation results, indicating that the selectivities for a 1:1 D2/H2 mixture at 20 K are larger than the values reported so far; especially, it shows a record value of 53.8 at 25 kPa. This demonstrates that this MOF is a promising candidate for highly effective hydrogen isotope separation.

For the modeling of near infrared spectroscopy (NIRS), the accuracy of the basic data, the stability of the spectra and the optimality of variables selection method were the important factors. In this paper, a novel optimization strategy for NIRS modeling was proposed, which was formed by data mean and ratio of absorbance to concentration (RATC) methods. The data mean method was aim to obtain accurate basic data and stable spectra, the RATC method was aim to select the optimal variables and compared with other variables selection methods (FiPLS, BiPLS, CC, UVE). The experimental subject was raw human plasma, with this novel optimization strategy, the predictive capability of NIRS model of its total protein (TP) content had been improved. At the same time, the public NIRS testing data (water, protein, oil, starch of corn and octane of gasoline) were used to verify the proposed variables selection method, and the predictive capability of these models of different parameters were also improved. To some extent, the optimization strategy of NIRS modeling provided theoretical supports for the development of protein content analyzer of NIRS and the quick determination of parameters of biologics and other materials.

Polydatin is a traditional Chinese medicine that provides myocardial protection after acute myocardial infarction (AMI). The study aim was to investigate the myocardial protection polydatin in H9c2 myocardial cells cultured in a hypoxic atmosphere and in a rat AMI model induced by ligating the left anterior descending coronary artery and treated with polydatin 100 mg/kg/day for 30 days. The involvement of Nrf2 in mediating the effects of polydatin was investigated in H9c2 cells following Nrf2 knockdown by transfection of siRNA. Polydatin suppressed hypoxia-induced H9c2 cell apoptosis and reactive oxygen species (ROS) generation by promoting Nrf2/HO-1 signaling. Nrf2 knockdown reversed the protective effects of polydatin against hypoxia-induced myocardial cell injury. The in vivo results were consistent with polydatin suppression of apoptosis and ROS generation in myocardial tissue by promotion of Nrf2/HO-1 signaling. In conclusion, polydatin effectively inhibited hypoxia- and AMI-induced myocardial damage by promotion of Nrf2/HO-1 signaling.

Though various efforts on modification of electrodes are still undertaken to improve the efficiency of perovskite solar cells, attributing to the large scope of these methods, it is of significance to unveil the working principle systematically. Herein, inverted perovskite solar cells based on indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)/CH3 NH3 PbI3 /phenyl-C61-butyric acid methyl ester (PC61 BM)/buffer metal/Al are constructed. Through the choice of different buffer metals to tune work function of the cathode, the contact nature of the active layer with the cathode could be manipulated well. In comparison with the device using Au/Al as the electrode that shows an unfavorable band bending for conducting the excited electrons to the cathode, the one with Ca/Al presents a dramatically improved efficiency over 17.1%, ascribed to the favorable band bending at the interface of the cathode with the active layer. Details for tuning the band bending and the corresponding charge transfer mechanism are given in a systematic manner. Thus, a general guideline for constructing perovskite photovoltaic devices efficiently is provided.

Nanowire (NW) structures is an alternative candidate for constructing the next generation photoelectrochemical water splitting system, due to the outstanding optical and electrical properties. NW photoelectrodes comparing to traditional semiconductor photoelectrodes shows the comparatively shorter transfer distance of photo-induced carriers and the increase amount of the surface reaction sites, which is beneficial for lowering the recombination probability of charge carriers and improving their photoelectrochemical (PEC) performances. Here, we demonstrate for the first time that super-long Cu2O NWs, more than 4.5 μm, with highly efficient water splitting performance, were synthesized using a cost-effective anodic alumina oxide (AAO) template method. In comparison with the photocathode with planar Cu2O films, the photocathode with Cu2O NWs demonstrates a significant enhancement in photocurrent, from –1.00 to –2.75 mA/cm2 at –0.8 V versus Ag/AgCl. After optimization of the photoelectrochemical electrode through depositing Pt NPs with atomic layer deposition (ALD) technology on the Cu2O NWs, the plateau of photocurrent has been enlarged to –7 mA/cm2 with the external quantum yield up to 34% at 410 nm. This study suggests that the photoelectrode based on Cu2O NWs is a hopeful system for establishing high-efficiency water splitting system under visible light.

An efficient, mild, and metal-free approach to direct diazenylation of N-heterocyclic compounds with aryltriazenes using Bronsted ionic liquid as a promoter has been developed for the first time. Many N-heterocyclic azo compounds were synthesized in good to excellent yields at room temperature under an open atmosphere. Notably, the promoter 1,3-bis(4-sulfobutyl)-1H-imidazol-3-ium hydrogen sulfate could be conveniently recycled and reused with the same efficacies for at least four cycles.

An efficient synthesis of novel 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) and their derivatives, using Brønsted acidic ionic liquid [C2O2BBTA][TFA] as a catalyst, from the condensation of aryl aldehyde, β-ketoester and urea was described. Reactions proceeded smoothly for 40 min under solvent-free conditions and gave the desirable products with good to excellent yields (up to 99%). The catalyst could be easily recycled and reused with similar efficacies for at least six cycles.

BiVO4 photonic crystal inverse opals (io-BiVO4) with highly dispersed Ag nanoparticles (NPs) were prepared by the nanosphere lithography method combining the pulsed current deposition method. The incorporation of the Ag NPs can significantly improve the photoelectrochemical and photocatalytic activity of BiVO4 inverse opals in the visible light region. The photocurrent density of the Ag/io-BiVO4 sample is 4.7 times higher than that of the disordered sample without the Ag NPs, while the enhancement factor of the corresponding kinetic constant in photocatalytic experiment is approximately 3. The improved photoelectrochemical and photocatalytic activity is benefited from two reasons: one is the enhanced light harvesting owing to the coupling between the slow light and localized surface plasmon resonance effect; the other is the efficient separation of charge carriers due to the Schottky barriers.