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[Display omitted] • Au-modified TiO 2 nanorod arrays were synthesized via a two-step method. • The Au/TiO 2 exhibited excellent n-butanol sensing performances. • The enhanced sensitivity mechanism of Au/TiO 2 was discussed detailed. • The experimental results are verified by first-principles calculation. In this paper, TiO 2 nanorod arrays were grown on FTO via a simple hydrothermal method. Then Au nanoparticles with an average size of ∼ 6 nm were modified on the surface of TiO 2 nanorods (NRs) using magnetron sputtering technology. The gas-sensing performance of pristine TiO 2 and Au-modified TiO 2 samples were systematically tested. The Au/TiO 2 -based sensors exhibited better gas-sensing properties to n-butanol gas than pristine TiO 2 sensors, including high sensitivity, lower working temperature, and faster response and recovery time. And 10 s-Au/TiO 2 sensor showed the highest response (S = 25) to 100 ppm n-butanol gas at 240 °C, which was 5 times higher than that of pristine TiO 2. Furthermore, the adsorption energies of TiO 2 and Au/TiO 2 surface to n-butanol molecules were calculated using first-principles calculations. It is revealed that the enhanced n-butanol sensing performance of Au/TiO 2 sensor is mainly attributed to the catalytic effects and chemical sensitization of Au toward n-butanol gas. The study confirms that Au-modified TiO 2 nanorods have great potential for application in n-butanol sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pt-modified TiO 2 nanorod arrays were synthesized via a two-step method. • The response of 1.5-Pt/TiO 2 sensor to 20 ppm CO is 3.83 at 360 °C. • The enhanced sensitivity mechanism of Pt/TiO 2 was discussed detailed. • The experimental results are verified by first-principles calculation. In this work, highly regular TiO 2 array films consisting of nanorods with a diameter of ∼119 nm were grown on FTO via a facile hydrothermal method. Then Pt nanoparticles with a size of ∼5 nm were modified on the surface of TiO 2 nanorods via an in-situ reduction process. The gas-sensing performances of pristine TiO 2 and Pt-modified TiO 2 samples were systematically tested. The introduction of Pt nanoparticles could enhance the response and stability toward CO gas and decrease the optimal operating temperature from 400 °C to 360 °C. And the Pt/TiO 2 -based sensor with a Pt content of 1.5 wt% exhibits the maximum CO sensitivity. Furthermore, the adsorption energies of Pt-modified or Pt-doped TiO 2 for CO molecules were calculated using first-principles calculations. The chemical sensitivity of Pt to CO molecules may be responsible for the improved CO sensitivity. Additionally, the unique nanorod array structure of Pt/TiO 2 and the nano-Schottky junction generated between them are helpful in enhancing the gas-sensing property. [ABSTRACT FROM AUTHOR]

[Display omitted] • In this paper, a synergistic construction strategy of rare earth element doping and morphology control techniques is described. • The strategy achieves preferential doping of the 1 0 1 crystalline surface with rare earth elements to promote the reaction of photogenerated electrons on the surface with the enriched chemisorbed oxygen to generate superoxide radicals, thus enhancing the efficiency of TiO2 photocatalytic degradation of pesticides. • Meanwhile, the strategy employs a self-sacrificing template. Compared with the complexity of conventional template construction methods, the proposed construction method is simple, economical, stable, and has excellent potential for application. • This study highlights the superiority and broad prospects of the synergistic strategy of elemental doping and morphology control techniques in photocatalytic materials, which can stimulate the interest of readers. In this study, using a solvothermal technique, we created several rare earth element-doped TiO 2 hollow nanobox catalysts. A variety of characterization techniques were used to examine the basic physicochemical features of the synthesized samples. The results reveal that rare earth element can be preferentially incorporated into the unit cells of TiO 2 hollow nanoboxes and replace titanium atoms, leading to an increase in the electron transfer rate and an extension of the light absorption of hollow-structured TiO 2 from the UV to the visible region. Meanwhile, rare earth element doping promotes the reaction of electrons clustered in the highly exposed (1 0 1) crystal plane with chemisorbed oxygen to generate superoxide radicals, thereby improving photocatalytic degradation activity. In the activity test, the Tm-TiO 2 samples showed the greatest photocatalytic degradation activity among others. And the degradation rate reached more than 90% under ultraviolet light in 90 min. Furthermore, DFT calculations indicate that the band gap of TiO 2 (0 0 1) is lower than that of TiO 2 (1 0 1). This suggests that the (0 0 1) crystal plane is more easily excited, and photogenerated electron-hole separation occurs. Moreover, the separated electrons transfer to the (1 0 1) crystal plane, effectively inhibiting electron-hole recombination. [ABSTRACT FROM AUTHOR]

Actinomorphic flower-like SnO 2 nanorods (NRs) were synthesized and then decorated by CuO nanoparticles (NPs) with diameter of 25 nm through a modified two-step process. The length and diameter of SnO 2 NRs are about 0.4–1.8 μm and 60–200 nm, respectively. The gas-sensing testing results indicate that such unique CuO/SnO 2 nanostructures exhibit an observably improved isopropanol sensing properties compared to the pure SnO 2 NRs. The sensitivity of CuO/SnO 2 sensor to 100 ppm isopropanol is 50.4, which is two time higher than that of the pure SnO 2 sensor (22.1). The gas sensing mechanism may be related to p-CuO/n-SnO 2 heterojunction formed at the interface of two oxides materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Atomic layer deposition technic was used to modify protein-based fibers. • ZnO nano film was controllably deposited on the surface of silk fabrics. • Modified silk had antibacterial properties while preserving favorable properties. As a natural protein resource, silk has been favored for thousands of years due to remarkable properties and the lustrous appearance. The broaden use of natural silk promotes it to become a high-tech fiber, which is undesirably hindered by the high hygroscopicity that provides conditions for bacterial growth thus accelerates the corrosion of silk. Functional surface modification can pose as compensation, but traditional nanoscale coating approaches come at the expense of inherent properties. In this work, ultrathin zinc oxide (ZnO) was uniformly deposited on silk fabrics in nanoscale using the atomic layer deposition (ALD) strategy. Different layers of ZnO were deposited by controlling the deposition cycles in the ALD process to evaluate the influences in antibacterial performances. The ZnO coated silk fabrics showed neglectable differences in morphologies compared with the raw silk fabric while manifesting excellent antibacterial properties against E. coli and S. aureus. The ZnO layer had insignificant influence on mechanical and air permeable properties, which guaranteed the wearable properties of silk fabrics. This work contributes to an innovative modification method for natural and wearable protein fibers with antibacterial properties in a controllable and uniform way. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Sn doped TiO 2 (Sn-TiO 2) coating CsPbBr 3 perovskite quantum dots to prepared core–shell CsPbBr 3 /Sn-TiO 2 nanocrystals. • The CsPbBr 3 /Sn-TiO 2 prepared using solution techniques such as supersaturation recrystallization, sol–gel coating, and solvothermal crystallization. • The CsPbBr 3 /Sn-TiO 2 have wider absorption range and higher photocatalytic activity. • The CsPbBr 3 /Sn-TiO 2 can sustainably work in the aqueous system for a long time. All-inorganic perovskite materials have attracted much attention in the field of photocatalysts due to their unique photoelectric properties.However, the inherent poor stability of perovskite quantum dots significantlyhinders their practical applications. Herein, to settle the instabilities of inorganic perovskite materials, Sn-TiO 2 coated CsPbBr 3 quantum dots named CsPbBr 3 /Sn-TiO 2 , are fabricated via resaturated recrystallization, sol–gel coating and solvothermal crystallization.The XRD results demonstrated that the core–shell structure of CsPbBr 3 /Sn-TiO 2 nanocrystals was successfully synthesized.Moreover, excellent dispersion is verified for CsPbBr 3 /Sn-TiO 2 nanocrystals with a core–shell structure by TEM. The particle size of CsPbBr 3 /Sn-TiO 2 nanocrystals is 15–30 nm, where the core size for CsPbBr 3 quantum dots is 4–8 nm, and the Sn-TiO 2 shell thickness is 2–8 nm.The photocatalytic activity of nanocomposites was studied by the photodegradation of RhB aqueous solution under the irradiation of 100 mWcm−2 air mass 1.5 global AM1.5G sunlight. Compared with traditional photocatalyst P25, the core–shell structured CsPbBr 3 /Sn-TiO 2 nanocrystals exhibited better photocatalytic performance, with a degradation efficiency of 96.6% and a degradation rate constant of 10.68 × 10-2 min−1 in 30 min of catalytic time, which was five times higher than that of P25.The core–shell structured CsPbBr 3 /Sn-TiO 2 nanocrystals have long-term stability in water system and have potential practical application value in the field of environmental governance. [ABSTRACT FROM AUTHOR]

Hierarchical porous SnO 2 (HP-SnO 2 ) nanoparticles (NPs) were synthesized via a modified sol-gel method by employing polystyrene (PS) microspheres as a template and SnCl 2 as a tin source. The samples presented a three-dimensional random arrangement of macropores with average pore diameter of about 210 nm, of which the pores walls were composed of NPs with the size of about 11 nm. The N 2 -sorption analysis showed that the presence of the hierarchical mesoporous structure in the samples. The gas-sensing measurements showed that the response of HP-SnO 2 based sensor reached the maximum value at the operating temperature of 240 °C, which was 60 °C lower than that of SnO 2 based sensor. Moreover, the HP-SnO 2 exhibited a significant improvement for the response and a short response-recovery time to ethanol vapor. The results indicated that HP-SnO 2 NPs were of great potential for application in ethanol sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-speed spin-coated cetyltrimethylammonium bromide (CTAB) solution passivated the surface of perovskite films. • Br- and ammonium groups contained in CTAB effectively bond ionic vacancy defects in the perovskite film during the passivation process. • After CTAB treatment, the quality of perovskite film was improved, and the optimized device had better photovoltaic performance. • Hydrophobic modification of the surface of perovskite films by CTAB improved the compatibility of the interface between perovskite layer and hydrophobic carbon electrode and enhanced the stability of PSCs. Organic–inorganic hybrid perovskite materials with mixed organic cations (FA x MA (1-x) PbI 3) have attracted intensive attention due to their superior optoelectronic properties. In this work, the FA 0.3 MA 0.7 PbI 3 perovskite film were synthesized and applied in perovskite solar cells (PSCs) based on carbon counter electrode (CCE). And a passivation approach for the perovskite/CCE interface is presented, using cetyltrimethylammonium bromide (CTAB). The quaternary amine and bromine ion of CTAB can fill the vacancy defects of FA/MA and iodine ion, respectively, leading to a more hydrophobic and smoother surface than the untreated film. The optimum device based on 0.5 mg/ml CTAB exhibited an short-circuit current density of 23.68 mA·cm−2 with a power conversion efficiency of 12.69%, which is superior to PSCs without CTAB. The long-term stability test in ambient atmosphere with 40% relative humidity reveals the higher stability of PSCs with the surface passivation, which is favorable for its commercial application. [ABSTRACT FROM AUTHOR]

In the next generation power electronics packaging, sinter Ag joining technology has become popular for use as a die attach and is receiving greater attention. Herein, it is reported that sinter Ag particles joining performed directly on a bare Cu substrate coated by a single-layer graphene can provide satisfactory interfacial oxidation protection and mechanical reliability. The shear strength obtained in our research achieved 25.4 MPa in low temperature, pressure-free sintering in air. The Cu oxide layer appeared solely at the location of Cu grain boundaries during sintering and was much smaller than when performed on substrates without graphene coating. The bonding mechanism was realized by Ag nanoparticles (AgNPs) self-generated from the Ag paste during the sintering process which tightly bonded to the graphene surface upon interacting with the Cu oxide. A subsequent high temperature (250 °C) aging test demonstrated that die shear strength maintains its value as-sintered for 750 h. Furthermore, the thickness of Cu oxide with graphene coating was about one fourth of that without graphene and this difference increased with aging time. This study puts forward an exciting solution for sinter Ag joining directly on Cu-based substrates in high temperature for longer lifetime in power electronic packaging applications. Unlabelled Image • Ag sinter joining was conducted on bare Cu covered by single-layer graphene. • In suit formed Ag nanoparticles tightly bonded to the graphene surface. • The thickness of Cu oxide with graphene coating was much smaller that without graphene. • Single-layer graphene provided satisfactory interfacial oxidation protection and mechanical reliability. [ABSTRACT FROM AUTHOR]