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A group of new iridium(III) complexes were rationally designed and synthesized with 2‐phenylbenzo[d]oxazole (bo), 2‐phenylbenzo[d]thiazole (bt), 2‐(thiophen‐2‐yl)benzo[d]thiazole (thbt), and 2‐(selenophen‐2‐yl)benzo[d]thiazole (sebt) as C^N ligands and bis(diphenylthiophosphoryl)amide (S‐tpip) as ancillary ligand. They are phosphorescent in a wide region of green to red with short lifetimes around 0.31–0.98 μs and quantum yields up to 64.7%. The detailed photophysical properties were investigated by experiment and further supported by density functional theory (DFT) calculation. These research results show that the spectroscopic properties are tuned by the replacement between oxygen, sulfur, and selenium or the change in aromatic ring. It has been demonstrated that the lowest energy‐level absorption and emission are dominated apparently by C^N ligands, and are ascribed to metal‐to‐ligand charge transfer (MLCT) and intra‐ligand charge transfer (ILCT) characters. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) analysis has attracted accumulated attention on diagnosis of diseases and high-efficiency photosensitizers are urgently needed. In this work, N-doped sheet-like porous carbon (N-PC) was prepared by thermal stripping of Zn2+ from zeolitic imidazole framework-8 (ZIF-8), followed by in situ formation of gold nanoparticles (Au NPs) embedded in the N-PC (termed Au NPs@N-PC). Also, the zinc meso-tetra (4-carboxyphenyl) porphine (ZnP) behaved as photosensitizer, which was covalently linked with Au NPs@N-PC (ZnP-Au NPs@N-PC), achieving the 9.2-fold enhancement in the photocurrents by using dopamine (DA) as donor. Next, the PEC mechanism was strictly discussed by UV–vis diffuse reflectance (DLS) spectroscopy, fluorescence (FL) and density functional theory (DFT) calculations. By virtue of the excellent PEC property, a label-free "signal off" PEC aptasensor was constructed based on the ZnP-Au NPs@N-PC for ultrasensitive detection of protein tyrosine kinase (PTK-7). The established biosensor showed a wider linear range of 10.00 pg mL−1 to 1.00 μg mL−1 (R 2 = 0.99) and a lower limit of detection (LOD, 1.42 pg mL−1), coupled by showing acceptable results for diagnosis of gliomas. Hence, this research opens a valuable avenue for synthesis of advanced photosensitizer and holds huge potential in biomedical field. • The Au NPs were in situ embedded on the pores of the N-PC. • The Au NPs@N-PC promoted photoelectron transfer of ZnP for signal enhancement. • The PEC biosensor was built for the detection of PTK-7 in glioma samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • LFTCO absorbent was created by introducing Ti and Co transition metals in B sites of perovskite oxides LaFeO 3. • Ferromagnetic LFTCO exhibits a methyl blue adsorption capacity (q max) of 2131 mg/g. • The electrostatic force and chelation linkage were the main driving forces in the chemisorption of MB on LFTCO. • A novel dual-doped method gives LFTCO exceptional adsorption capabilities and Fenton-based regeneration potential. Creating adsorbents that exhibit high selectivity towards pollutants, can be readily regenerated, and maintain high stability, remains a crucial challenge in water treatment technology. Herein, we present a magnetically and chemically recoverable absorbent based on Ti and Co co-substituted LaFeO 3 (La 0.9 Fe 0.55 Ti 0.3 Co 0.15 O 3 , LFTCO) with significantly enhanced adsorption properties. Notably, LFTCO exhibits a methyl blue adsorption capacity (q max) of 2131 mg/g, setting a new record among perovskite oxides, due to the increased surface oxygen vacancy with the dual doping strategy. The selected dual-dopant consists of Fenton active Co and spin-state interactive Ti, which allows creating more oxygen vacancy and simultaneously facilitating pragmatic regeneration of the adsorbent. The new LFTCO exhibits significantly enhanced ferromagnetism (M = 7.27 emu/g), enabling rapid magnetic separation from water and subsequent Fenton-based regeneration step. We also reveal that the anchored configuration of SO 3 -defect site, through density functional theory (DFT) calculation, as the most favorable site for the adsorption process. These findings provide a pathway to creating high-performance adsorbents and shed light on the mechanistic understanding of LFTCO's enhanced adsorption properties. [ABSTRACT FROM AUTHOR]

Synergistic implementation of corrosion inhibitors is an efficient and economic method for metal protection. The adsorption dynamics and inhibition behavior of 2-phenyl imidazoline (2-PI) and benzotriazole (BTA) are investigated in atmospheric and aqueous environments by electrochemical and quartz crystal microbalance sensors. Moreover, their synergistic mechanisms are illustrated from molecule scales by theoretical calculations. Electrochemical tests show that 2-PI and BTA exhibit promising synergistic effects on the corrosion of copper with inhibition efficiency up to 99.1% in 0.1 mol/L NaCl solution and 94.1% in the atmosphere, respectively. In addition, the adsorption kinetics of inhibitors on copper obey a pseudo-first-order kinetic model characteristic of exponential damping. Quantum chemical and molecule dynamic calculations also suggest that there exists an intermolecular interaction between 2-PI and BTA molecules in a parallel adsorption manner when they are co-adsorbed on the surface of copper. • 2-PI+BTA azole composite features synergistic corrosion inhibition in both atmospheric and aqueous environments. • Adsorption of azole on Cu obeys pseudo-first order exponential damping kinetics. • 2-PI and BTA present intensive electrostatic interaction facilitating a more compact adlayer. [ABSTRACT FROM AUTHOR]

Constructing amorphous/intermetallic (A/IMC) heterophase structures by breaking the highly ordered IMC phase with disordered amorphous phase is an effective way to improve the electrocatalytic performance of noble metal‐based IMC electrocatalysts because of the optimized electronic structure and abundant heterophase boundaries as active sites. In this study, we report the synthesis of ultrathin A/IMC PtPbBi nanosheets (NSs) for boosting hydrogen evolution reaction (HER) and alcohol oxidation reactions. The resulting A/IMC PtPbBi NSs exhibit a remarkably low overpotential of only 25 mV at 10 mA cm−2 for the HER in an acidic electrolyte, together with outstanding stability for 100 h. In addition, the PtPbBi NSs show high mass activities for methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR), which are 13.2 and 14.5 times higher than those of commercial Pt/C, respectively. Density functional theory calculations demonstrate that the synergistic effect of amorphous/intermetallic components and multimetallic composition facilitate the electron transfer from the catalyst to key intermediates, thus improving the catalytic activity of MOR. This work establishes a novel pathway for the synthesis of heterophase two‐dimensional nanomaterials with high electrocatalytic performance across a wide range of electrochemical applications. [ABSTRACT FROM AUTHOR]

Constructing amorphous/intermetallic (A/IMC) heterophase structures by breaking the highly ordered IMC phase with disordered amorphous phase is an effective way to improve the electrocatalytic performance of noble metal‐based IMC electrocatalysts because of the optimized electronic structure and abundant heterophase boundaries as active sites. In this study, we report the synthesis of ultrathin A/IMC PtPbBi nanosheets (NSs) for boosting hydrogen evolution reaction (HER) and alcohol oxidation reactions. The resulting A/IMC PtPbBi NSs exhibit a remarkably low overpotential of only 25 mV at 10 mA cm−2 for the HER in an acidic electrolyte, together with outstanding stability for 100 h. In addition, the PtPbBi NSs show high mass activities for methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR), which are 13.2 and 14.5 times higher than those of commercial Pt/C, respectively. Density functional theory calculations demonstrate that the synergistic effect of amorphous/intermetallic components and multimetallic composition facilitate the electron transfer from the catalyst to key intermediates, thus improving the catalytic activity of MOR. This work establishes a novel pathway for the synthesis of heterophase two‐dimensional nanomaterials with high electrocatalytic performance across a wide range of electrochemical applications. [ABSTRACT FROM AUTHOR]

We report successful growth of millimeter-sized high quality single crystals of V 3 S 4 , a candidate topological semimetal belonging to a low-symmetry space group and consisting of only low atomic number elements. Using density functional theory calculations and angle-resolved photoemission spectroscopy, we show that the nonmagnetic phase of monoclinic V 3 S 4 hosts type-II Dirac-like quasiparticles which opens a sizable gap due to spin orbit coupling, as well as theoretical multiple nodal lines that are eliminated also by spin orbit coupling. These results suggest that relativistic effects give rise to profound modifications of the topological properties even in compounds with low-weight elements. • We report successful growth of high quality millimeter-sized V3S4 single crystals by chemical vapor transport method. • We show that V3S4 possesses both type-II Dirac cones and topological nodal lines in its nonmagnetic phase without SOC. • When SOC is included, the Dirac point opens a 120 meV gap, and all topological nodal lines vanish. [ABSTRACT FROM AUTHOR]

[Display omitted] • The calculational scheme for predicting the PCE of DSSC is constructed. • Power conversion efficiencies of PUB and PEB as sensitizers of DSSC are evaluated. • Highest Power conversion efficiencies of PUB and PEB can reach 11.05 % and 9.73 %. • Three different ways of PUB and PEB adsorbed on TiO 2 (1 0 1) surface are considered. The power conversion efficiency (PCE) of phycoerythrobilin (PEB) and phycourobilin (PUB) as sensitizers of dye-sensitized solar cells is investigated by employing the first-principles calculations. We constructed a model for the adsorption of PEB/PUB on the surface of TiO 2 in three different ways. The geometrical configurations of the PEB/PUB-TiO 2 complexes are optimized, and the electronic properties are determined based on the first-principles calculations. The short-circuit current density, open-circuit voltage, and filling factor are obtained based on the band alignments of the complex and the optical absorptions of PEB/PUB. The D149 dye is used to assess the validity of our method. The obtained PCE of 5.56 % corresponds to the experimental 5.4 %, confirming the credibility of the current method. The highest PCEs of PUB and PEB are predicted at 11.05 % and 9.73 %, which implies that the two molecules are promising candidate sensitizers of the dye-sensitized solar cell. [ABSTRACT FROM AUTHOR]

• Secondary and tertiary carbamates are prepared in high efficiency in an unprecedentive strategy. • Active transition metal-functionalized MOFs are synthesized via an in situ -grown protocolunder solvent-free mechanochemical conditions. • Both aminesand aniline are well tolerated. The solvent-free synthesis of MOF represents a promising and environmentally benign protocol. This paper outlines a green one-pot mechanochemical method for the synthesizing of UiO-66 in the absence of solvent, along with the implantation of three different metals (Cu, Ni, and Pd) into the defect sites. The materials have proven to be effective catalysts in the transformation between azidocarbonate and amines/anilines in moderate to excellent isolated yields (up to 94%), exhibiting better advantages compared with the exiting methodologies. More interestingly, Cu and Ni exhibited very good catalytic performance towards primary and secondary amines, respectively. It also should be noted that high yield was still observed after six cycles. Our work presents a novel and straightforward strategy for the preparation of secondary and tertiary carbamates in an unprecedented fashion, greatly enriched the toolbox for the synthetic community. Moreover, the combination of experimental studies and density functional theory (DFT) calculations gave more insight and evidence for the mechanism. Accompanied by the advantages of the effective and recyclable catalyst, the broad substrate scope, good functional group tolerance, and excellent reaction yields made the established method attractive in heterogeneous catalysis and the carbamates synthesis. [Display omitted] [ABSTRACT FROM AUTHOR]

Although the MOS gas sensors are widely employed to detect gas owing to the excellent sensing performance in fast response and recovery time and high sensitivity. However, the poor selectivity is among the most severe challenge to determine the homogeneous gases, especially when CO and H 2 coexist. The sensors have the same gas sensing response to homogeneous gases, which attribute to the cross-sensitivity. Herein, a facile sol-gel method has been used to prepare SnO 2 -xNiO composites and the sensing performances of sensors are further investigated using XRD, TEM, XPS. The experimental results indicate that the selectivity of SnO 2 -based gas sensor to CO and H 2 can be improved by modulating electron and hole concentration in the p-n composites. Interestingly, the gas sensing results show that SnO 2 -3.58NiO sensor annealed at 550 °C worked at 350 °C presents opposite sensing response to homogeneous gases CO and H 2 , that is, p-type response to CO but n-type to H 2. Insight into the interactions between CO and H 2 target gas molecules with SnO 2 and NiO surfaces in addition to the target gas-dependent modulation of SnO 2 and NiO conductivity are investigated through density functional theory calculations supporting the experimental results. The opposite gas sensing behavior of the SnO 2 -3.58NiO composites to both gases suggests that the SnO 2 -3.58NiO composite can distinguish between CO and H 2. This paper provides an approach to effectively enhance this type gas sensor selectivity. [Display omitted] • SnO 2 -xNiO heterojunction gas sensors are fabricated that show a p-type and an n-type response to H 2 and CO, respectively. • The opposite sensing mechanism of SnO 2 -xNiO NPs to CO and H 2 is proposed experimentally and theoretically. • First report on optimized band structures of NiO and SnO2 thin films with corrected bandgaps, enabling conductivity modulation and sensing analysis. • Atomistic scale insight into the interactions between the target molecules and the sensing materials is provided. • Excellent agreement between the experimental nanoscale observations and the atomic-scale first principle simulations are achieved. [ABSTRACT FROM AUTHOR]

Silicon nitride based materials have emerged as the promising candidates for high-power electronics and next-generation gate dielectrics. Herein, the crucial characteristics of electron mobility and lattice thermal conductivity of β -Si 3 N 4 are investigated from first-principles. The predicted electron mobility and averaged lattice thermal conductivity is 228.4 cm2/Vs and 325.06 W/m·K at 300 K, which demonstrates a good agreement with literature data. The electron mobility exhibits strong temperature-dependence at a low carrier concentration where the polar-optical phonon scattering dominates. For the heavy doping case, the ionized impurity scattering becomes dominant. A well-trained momentum tensor potential (MTP) with an accuracy comparable to density functional theory shows advantages in predicting thermal transport properties over a large-scale system containing thousands of atoms. The relaxation lifetimes for heat-carrying acoustic phonons are over tens of picoseconds which can explain the high thermal conductivity of β -Si 3 N 4 , but the nanoscale grain size crucially limits the thermal transport properties. • POP scattering primarily limits electron mobility at low doping concentrations. • Electron mobility is temperature-independent at heavily doping concentrations. • The MTP potential is trained with an accuracy comparable to DFT. • Long lifetimes for heat-carrying acoustic phonons are predicted. • The nanoscale grain size crucially limits thermal conductivity of β -Si 3 N 4. [ABSTRACT FROM AUTHOR]

[Display omitted] • New 2D heterojunctions of TiO 2 /Ti 3 CN MXene were synthesized and employed as the photocathode in PEC CO 2 reduction. • Ti3+ species could activate CO 2 molecules and benefit to the generation of ethanol and formate. • DFT calculations were performed to explain the mechanism of PEC CO 2 reduction. Converting CO 2 into chemicals is a promising avenue to mitigate the energy crisis and global warming. Herein, two-dimensional (2D) heterojunctions of TiO 2 /Ti 3 CN MXene were fabricated through a facile hydrothermal oxidation method and used as the photocathode in photoelectrocatalytic (PEC) CO 2 reduction. The in situ grown TiO 2 /Ti 3 CN heterojunctions demonstrate excellent light absorption abilities, possess large specific surface areas and Ti3+ species, which are beneficial to the generation and transportation of photoelectron-hole pairs. In a new PEC system of Pd@TiO 2 /Ti 3 CN||SCE||BiVO 4 , formate, methanol and C 2 of ethanol were obtained as the major reduction products, with the maximum and total formation rate of 45.6 μM cm−2h−1. Furthermore, density functional theory (DFT) calculations indicate that TiO 2 /Ti 3 CN heterojunction can spontaneously activate CO 2 and stabilize the key reaction intermediates for facilitating HCOOH production. This research highlights the great prospect of titanium carbonitrides MXene in the green energy conversion field. [ABSTRACT FROM AUTHOR]

[Display omitted] • The GQD2-PEB nanocomposite is identified as the favorable candidate sensitizer. • The feasibility of GQD and PEB/PUB nanocomposites as sensitizers is examined. • The significant spatial charge separation is identified for GQD2-PEB. • Molar extinction coefficients of the nanocomposite are significantly enhanced. The feasibility of nanocomposites of phycourobilin (PUB) and phycoerythrobilin (PEB) with graphene quantum dot (GQD) as a dye-sensitized solar cell (DSSC) sensitizer is studied based on the first-principles density functional theory including solvent effect. We construct and optimize the geometrical configurations for the nanocomposites of GQD-PEB/PUB and confirm the stability by the vibrational frequency and formation energy. The results of electronic properties show that the GQD2-PEB nanocomposite could be a favorable candidate for the sensitizer of DSSC due to its apparent spatial charge separation, suitable energies of frontier orbital, and enhanced absorption coefficient in the large solar irradiance region. [ABSTRACT FROM AUTHOR]

[Display omitted] • Excellent thermoelectric behavior of the SiSe 2 monolayer and bulk are identified. • The ZT as a function of temperature and carrier concentration are obtained. • The maximum ZT s of 4.84 and 4.11 can be achieved for the monolayer and bulk at 700 K. • Both lattice thermal conductivities and thermoelectric properties are anisotropic. The excellent thermoelectric performance of the SiSe 2 monolayer and layered bulk is identified by employing the density functional theory and the semi-classical Boltzmann transport theory. The geometrical structures of the SiSe 2 monolayer and bulk are fully relaxed, and the dynamic and thermal stabilities have been confirmed through phonon dispersions and ab initio molecular dynamics simulations. By introducing a method to avoid the vacuum space of the supercell influence on the volume of the monolayer, we have obtained the lattice thermal conductivity, the Seebeck coefficient, electrical conductivity, power factor, and electron thermal conductivity for both the monolayer and the bulk. The ZT relative to temperature and carrier concentration are obtained to evaluate the thermoelectric performance. For the SiSe 2 monolayer, the maximum ZT can reach 4.84 at 700 K with the p -type carrier concentration of 9.60 × 1019 cm−3, while for the SiSe 2 bulk, the maximum ZT can also attain 4.11 at 700 K with the n -type carrier concentration of 2.38 × 1019 cm−3. Therefore, both the SiSe 2 monolayer and bulk are favorable candidates for thermoelectric applications. The mechanism for the superior thermoelectric properties is also examined. [ABSTRACT FROM AUTHOR]

ZrTe 5 was assigned as topological insulator or semimetal, which can be widely applied in electronic devices due to its various excellent properties. The first principle calculations based on density functional theory (DFT) were employed to investigate the pressure dependence of structural, electronic, optical and mechanical properties of ZrTe 5 with pressure up to 10 GPa. Due to the unique photovoltaic properties, such as high optical absorption coefficient of 105 cm−1, strong optical anisotropy, high dielectric function, and light effective masses, ZrTe 5 can be widely applied in optoelectronic equipment. Besides, the structural, electronic, and optical properties of ZrTe 5 have a strong response to pressure. Particularly, ZrTe 5 could undergo a metallic transition between 7 GPa and 8 GPa. Besides, as the applied pressure increases from 0 GPa to 1 GPa, ZrTe 5 exhibits mechanical instability. [Display omitted] • ZrTe5 owns superior conductivity due to the light effective mass of carriers. •ZrTe5 owns optical anisotropy, light absorption is strong in the visible region. •ZrTe5 exhibits mechanical instability at 1 GPa. •Pressure could improve the photoelectric performance of ZrTe5. [ABSTRACT FROM AUTHOR]