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[Display omitted] • For the first time, we have used CFBA passivation on CsPbI 2 Br film. • CFBA surface treatment assists to develop highly crystalline and compact film. • CFBA modification significantly reduced the trap-assisted density. • Optimized CFBA based PSC showed an impressive PCE of 17.07%. • A noticeable indoor PCE of 23.24% was found under LED light (3200 K, 1000 lx). All-inorganic α-CsPbI 2 Br perovskite has garnered considerable interest due to its optical bandgap (∼1.92 eV) suitable for tandem architectures and superior thermal stability. However, CsPbI 2 Br based perovskite solar cells (PSCs) exhibit severe energy loss due to presence of various surface defects like uncoordinated Pb2+ ions, halide ion vacancies and pinholes, which causes serious non-radiative recombination and limit the further improvement in power conversion efficiency (PCE). Surface passivation strategy is an effective approach to produce high quality α-CsPbI 2 Br film. Herein, we introduce fluorinated ionic liquid, 3-(Trifluoromethyl) benzylamine (CFBA), as surface passivating agent. The chemical analysis shows that the trifluoro (-CF 3) and amine groups of CFBA strongly interacted with perovskite surface via forming Pb-F and H-I bonding, respectively. The high electronegative fluoride atoms of -CF 3 group allow for electrostatic interaction with uncoordinated Pb2+ ions, which built a robust shield that protected against surrounding moisture as well. In addition, CFBA modification passivates the dangling bonds, enhanced crystallinity, reduced pinholes, improved the surface coverage and compactness, increased hydrophobicity, and decreased non-radiative recombination, leading to high PCE. With optimum concentration of 3 μL-CFBA, CsPbI 2 Br PSC revealed an impressive PCE of 17.07% with FF of 83.21% as compared to pristine device (PCE of 15.24% with FF of 79.81%). Moreover, champion device showed an excellent thermal stability by retaining ∼ 86.23% of its initial PCE, whereas pristine device maintained ∼ 48.26% of its original PCE after 1440 h aging at 85 ℃ in a dry box without any encapsulation. In addition, optimized PSC showed a decent indoor PCE of 23.24% as compared to pristine device (18.35%) under dim lighting conditions (LED, 3200 K) at 1000 lx. These results suggested that surface passivation strategy with CFBA is a promising approach for developing efficient all-inorganic CsPbI 2 Br outdoor/indoor PSCs with better thermal stability. [ABSTRACT FROM AUTHOR]

A low-cost and environment-friendly hydrothermal approach was used for the synthesis of layered V 2 O 5 /ZnV 2 O 6 hybrid nanobelts. Characterization results indicate that the V 2 O 5 /ZnV 2 O 6 nanobelts are composed of several thin layers. Additionally, it is illustrated that the chemical formation process of V 2 O 5 /ZnV 2 O 6 occurred in the solution. The synthesized V 2 O 5 /ZnV 2 O 6 heterostructures were subjected to detailed ethanol sensing tests. Results demonstrate that V 2 O 5 /ZnV 2 O 6 based sensor shows about 4.3 of response to 100 ppm of ethanol gases, reveals relatively high sensitivity at relatively low optimal operating temperature of 240 °C, as well as relatively good selectivity and stability. The performance of the sensor is better than most of reported vanadium based sensing devices. Thus this work offers a new insight into the rational regulation of vanadium based sensing devices. [ABSTRACT FROM AUTHOR]

A series of magnetic Ag/BiOI/ZnFe 2 O 4 hybrids synthesized via hydrothermal process, subsequent deposition-precipitation and photoreduction method were employed to remove elemental mercury (Hg 0 ) under fluorescent light irradiation. The effects of Ag content, fluorescent light irradiation, reaction temperature, pH value, flue gas composition, anions and photocatalyst dosage on Hg 0 removal were investigated in detail. The as-synthesized photocatalysts were characterized using N 2 adsorption-desorption, XRD, SEM, TEM, HRTEM, XPS, VSM, DRS, ESR, PL and photocurrent response. The results showed that the ternary Ag/BiOI/ZnFe 2 O 4 hybrids possessed enhanced visible-light-responsive photocatalytic performances for Hg 0 removal. Ag/BiOI/ZnFe 2 O 4 photocatalyst could be easily recovered from the reaction solution by an extra magnet and was stable in the process of Hg 0 removal. Lower content of Ag was highly dispersed on the surface of BiOI/ZnFe 2 O 4 , while higher content of Ag would result in some aggregations and/or the blockages of micropore. In comparison to BiOI/ZnFe 2 O 4 , Ag deposited BiOI/ZnFe 2 O 4 material showed lower recombination rate of electron–hole pairs. The superior Hg 0 oxidation removal could correspond to good match of BiOI and ZnFe 2 O 4 , excellent fluidity and surface plasmon resonance effect of Ag 0 nanoparticles, which led to higher separation efficiency of photogenerated electrons and holes, thereby enhancing the hybrids’ photocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Z-scheme BiVO 4 -Ni/AgVO 3 heterojunction photocatalytic material was successfully synthesized by simple electrospinning combined with hydrothermal method. • The synergistic effect of heterojunction composed of Ni-doped BiVO 4 and AgVO 3 effectively improves the separation efficiency of carriers. • BiVO 4 -Ni/AgVO 3 photocatalyst was used for photocatalytic reduction of Cr6+ and degradation of RhB to obtain excellent performance. In this study, we fabricated a novel heterostructured BiVO 4 -Ni/AgVO 3 nanofibers by combining the electrospinning approach and hydrothermal method. Benefiting from the synergetic strategy of Ni doping and AgVO 3 coupling, the specific surface area and visible-light absorption of BiVO 4 -Ni/AgVO 3 were both increased compared to BiVO 4. Meanwhile, the separation efficiency of photogenerated carriers was effectively improved through the formed impurity energy level and heterojunction. As a result, the optimal BiVO 4 -Ni-1/AgVO 3 -25 photocatalyst exhibited excellent photocatalytic reduction efficiency of 99.7% towards Cr6+ within 80 min, and also displayed superior degradation efficiency of 98.6% towards RhB within 30 min. Moreover, a Z-scheme charge transfer mechanism was explained for BiVO 4 -Ni/AgVO 3 according to the radical trapping experiments and band matching. The successful preparation of Z-scheme heterojunction BiVO 4 -based photocatalyst has essential application prospects in photocatalytic degradation of pollutants and reduction of metal ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The types of Schottky contacts and Schottky barrier heights of blueP-metal contacts were determined theoretically. • A picture of partial Fermi level pinning for blueP-metal contacts was depicted, and the reasons were elucidated. • The substrate coupling was demonstrated to alter the electronic and chemical properties of blueP-metal contacts. The contact nature when monolayer blue phosphorus (blueP) interfaces with three transition metal electrodes (i.e., Pd, Ir, and Pt) was unraveled by the ab initio density functional theory calculations. Specifically, n-type Schottky contact is observed for Ir(1 1 1)-blueP, in contrast, p-type Schottky contacts are formed for Pd(1 1 1)- and Pt(1 1 1)-blueP. The Fermi level is pinned partially at metal-blueP interfaces due to two interfacial behaviors: one being the modification of metal work function caused by interface dipole formation ascribed to a redistribution of charges, and the other being the production of gap states that are dominated by P p -orbitals since the intralayer P P bonds are weakened by the interfacial metal-P interactions. The incorporation of metal substrates would also significantly alter the chemical properties of the adsorbed monolayer blueP. The binding strength of hydrogen can be enhanced by as much as 0.9 eV, which resulted from two parts: one is the charge transfer from metal substrate to monolayer blueP rendering a stronger H P coupling; the other is a strong interfacial interaction after the hydrogen adsorption. The free energy change of H adsorption onto Ir(1 1 1)-blueP is as low as 0.16 eV which is comparable to the most efficient catalyst of Pt. These findings would provide theoretical guidance for the future design of electronic devices based on blueP and exploration of its potential in novel catalysts for hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel chemical etching for Sb 2 (S,Se) 3 film by KF solution was first proposed. • Properties of Sb 2 (S,Se) 3 film and interfacial defects of device are improved. • Mild gradient band gap is formed, promoting the carries transfer between the absorber and hole transport layer. • The device efficiency based on chemical etched Sb 2 (S,Se) 3 film reaches 9.58%. Recently, due to its excellent photovoltaic features, Sb 2 (S,Se) 3 is regarded as a promising photovoltaic absorber material. However, the interfacial property of Sb 2 (S,Se) 3 -based solar cell still needs to be studied due to limited efficiency improvement resulting from interfacial defects. In this paper, we focus on Sb 2 (S,Se) 3 film prepared by hydrothermal method to investigate the effects of surface modification on the properties of the Sb 2 (S,Se) 3 film as well as its solar cell performance. Interestingly, the chemical etching performed on Sb 2 (S,Se) 3 film using potassium fluoride aqueous solution not only improved the crystallinity and uniformity of Sb 2 (S,Se) 3 film but also decreased the interfacial defects, leading to a reduced carrier recombination loss of the device. As a result of chemical modification, the current density and fill factor of Sb 2 (S,Se) 3 -based superstrate structure solar devices were improved, resulting in maximum efficiency of 9.58%. Overall, this research offers a comprehensive understanding of the hydrothermally processed Sb 2 (S,Se) 3 film as well as a viable alternative method for reducing interfacial defects in other chalcogenide semiconductors. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-performance gas sensors based on reduced graphene oxide (rGO) fibers coated with MoS x Se 2-x. • Sensing materials can be optimized by engineering the chemical composition of TMD alloys. • TMDs-Decorated rGO Fiber with significantly enhanced recovery properties at room temperature. • rGO/MoS 1 Se 1 fibers have a great potential in sustainable gas sensing at room temperature. • Desorption of NO 2 molecules can be enhanced by increasing the ratio of Se to S atoms. Transition metal dichalcogenides (TMDs) possess great potential for use in gas sensing applications because, in contrast to conventional metal oxides, they have unique semiconducting properties with band gaps that can be tuned by adjusting thickness and composition. However, one issue is that their recovery time at room temperature is too long for them to be used practically in sustainable sensing applications. We found that incorporating Se atoms weaken interactions with gas molecules compared to when S atoms are used alone, therefore, the responsivity, as well as the recovery properties, of MoS x Se 2-x sensors were significantly enhanced by increasing the ratio of Se to S. Herein, we demonstrate high-performance gas sensors that are based on reduced graphene oxide (rGO) fibers coated with MoS x Se 2-x , the fabricated sensor could efficiently refresh its surface to allow fast, complete recovery at room temperature. Furthermore, it was shown that the porosity of rGO fibers with their large surface-to-volume ratio leads to enhanced sensing at room temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • Our approach, for the first time, using melamine nitrate as precursor, sodium borohydride as B source and Na source, by controlling the heating rate and thermal post-treatment, B/Na co-doped porous carbon nitride nanosheets were successfully prepared. • The as-synthesized B/Na co-doped porous g-C 3 N 4 nanosheets obtained wonderful photocatalytic hydrogen generation properties, AQE value of 9.39% under the radiation of 430 nm wavelength, and high-efficiency photocatalytic removal of TC performance. • The energy saving LED is used as the light source for hydrogen production. g-C 3 N 4 has attracted wide concern owing to its function of photocatalytic degradation of pollutants and H 2 production. However, the bulk carbon nitride (BCN) has many shortcomings, such as poor light absorption ability, short life of photogenerated electrons and few reactive sites. In this study, element doping and morphology control strategies were used to enhance their activity. B/Na co-doped porous carbon nitride nanosheets (PNCN-BNa-3) were successfully prepared by controlling the heating rate and thermal post-treatment using melamine nitrate as precursor, sodium borohydride as B source and Na source. Thanks to the synergistic effect of the porous nanosheets structure and B/Na co-doped, the B/Na co-doped porous g-C 3 N 4 nanosheets obtained wonderful photocatalytic hydrogen generation properties (5971.51 μmol·g−1·h−1), AQE value of 9.39% under the radiation of 430 nm wavelength, and high-efficiency photocatalytic removal of TC performance (the removal efficiency reached 78.39% in 30 min). This provides a new idea for the preparation of semiconductor photocatalysts with good property. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ball-on-disc wear tests performed in dry and ambient sliding conditions. • The hardness of deformed layer shows 63% higher than matrix due to grain refinement stimulated by sliding friction. • Three-layer deformation in worn surface identified as central mechanism. • Friction induced oxidation and subsurface grain refinement improved the wear resistance. In this study, equiatomic CoCrFeMnNi high entropy alloy (HEA) was fabricated by induction melting and subsequent thermomechanical treatments were carried out to achieve single FCC phase with equiaxed grains. The friction and wear behavior of HEA was investigated using ball-on-disc configuration in dry and ambient conditions under different sliding time, normal load and velocity. The detailed microscopic characterizations were invested to examine the worn surface and subsurface deformation mechanisms to identify the kinds of wear involved during dry sliding process. Results revealed the hardness of deformed layer showed 63% higher than matrix owing to grain refinement induced by sliding friction. The friction coefficient stabilized at longer sliding time due to oxidized wear debris acting as as lubricant behavior during sliding. While wear rate significantly decreased with increasing sliding time due to oxidation of wear debris on worn surface and formation of deformed layer with grain refinement resists the plastic deformation by strengthening the subsurface layers. On the other hand, wear rate stabilized for 6 and 8 N due to worn surface oxidation and subsurface hardening. Moreover, wear rate stabilized at higher sliding velocity owing to balance between subsurface hardening and delamination behavior. [ABSTRACT FROM AUTHOR]