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Efficient bifunctional OER/ORR catalysts are crucial for the further development of zinc-air battery. From a sustainable point of view, it is important that electrocatalysts are efficient, low cost, and composed of abundant resources instead of scarce metals. Due to their good conductivity, low cost, and strong durability, carbon-based materials are considered a promising alternative in the field of commercial zinc-air battery catalysts. Herein, we briefly introduce the zinc-air battery and then summarize recent progress in the development of carbon-based bifunctional catalysts by defect engineering, heteroatom doping and metal doping. Finally, we discuss the main challenges and prospects for the future development of carbon-based bifunctional oxygen catalysts.

Photo-thermal CO2 reduction with methane (CRM) is beneficial for solar energy harvesting and energy storage. The search for efficient photo-thermal catalysts is of great significance. Here, we reveal that group VIII metal catalysts supported by optical material WO3 are more effective for photo-thermal CRM, giving catalytic activities with visible light assistance that are 1.4–2.4 times higher than that achieved under thermal conditions. The activity enhancement (1.4–2.4 times) was comparable to that achieved with plasmonic-Au-promoted catalysts (1.7 times). Characterization results indicated that WO3 was partially reduced to WO3–x in situ under the reductive CRM reaction atmosphere, and that WO3–x rather than WO3 enhanced the activities with visible light assistance. Our method provides a promising approach for improving the activity of catalysts under light irradiation.

The coating design of machine tools refers to the exterior appearance of a machine tool and is an important method for improving the user experience and brand image. In this study, we studied and optimized the coating design of serial CNC cylindrical grinder machines of the Shanghai Machinery Factory in China using eye-tracking experiments and virtual reality technology. Firstly, based on eye-tracking technology, experiments were carried out on various elements of the coating design of the machine tools. Secondly, the experimental data were analyzed to extract design criteria that fit the user’s visual habits and to determine the details of the coating design optimization. Thirdly, the design scheme was verified using virtual reality technology and a user questionnaire survey. The results show that it provides support for the optimization of the design and working efficiency of machine tool coatings in enterprises. Future work should investigate optimization design tools that include ergonomics based on vision experiments and virtual reality.

Improving the alkali metal resistance of catalysts as well their catalytic activity is of great importance in propane oxidation, but current studies are rarely reported. Herein, we fabricated a one...

This study proposes a new optimized preparation method for Cu2ZnSnS4 (CZTS) absorbent film. The aim is to overcome the problems faced when the conventional sol–gel method is used, which includes a smaller grain size and a small nanoparticle layer present at the bottom of the film. Our absorbent layer preparation process is divided into two cycles. In the first cycle, a low-thickness precursor film is spin-coated on molybdenum-coated soda-lime glass (SLG) and then sulfurized once. In the second cycle, the sample obtained in the first cycle is used as the substrate for spin coating, so as to obtain a second low-thickness precursor film. This is then followed by the second sulfurization process, which achieves the final absorbent layer film. Surface and cross-sectional images from the scanning electron microscope (SEM) show that the prepared absorbent layer of the film has a dense surface and CZTS large grains penetrate it in its entirety, which effectively reduces the bottom fragmented grains. It is found that under the same experimental conditions, our method increases the PCE from the traditional method’s 1.66% to 3.60%. This thereby demonstrates the feasibility of the present method to improve the quality of the absorbent layer, which in turn has a certain significance for the further improvement of the efficiency of CZTS thin-film solar cells.

Synchronously achieving high-capacity and high-rate sodium-ion storage is critical for large-scale energy stationary applications of sodium-ion batteries (SIB). Here we present a facile bottom-up strategy to covalently encapsulate sulfur chains into carbon-rich nanomaterials by knitting 3,4-ethylenedioxythiophene (EDOT) with external crosslinking reactants. Using a series of ex situ characterization studies, the synergistic effects of the covalent sulfur species (21.33 wt%) are demonstrated on both increasing reversible electrochemical active sites/structural defects and expanding interlayer spacing, which endow the elaborate anode material with a high capacity of 456 mA h g−1 @ 0.1 A g−1, a desirable rate capability as high as 253.2 mA h g−1 @ 5 A g−1 for sodium-ion storage, and an excellent long-cycling performance with almost no decay after 5000 cycles @ 5 A g−1. Significantly, dynamic investigation indicates that the sodium-ion storage process and transfer kinetics are closely related to the covalently encapsulated sulfur chains. This work furnishes a new and systemic insight into the rational design of sodium-ion anode materials, in which the covalent sulfur chemistry may play a crucial role in reaching the supreme performance of sodium-ion batteries.

Hydrogenation reactions are an important process in today's chemical industry. Typically, hydrogenation reactions involve the removal of an unsaturated bond in olefins or other polyenes via thermal catalysis using hydrogen. As hydrogenation reactions are often carried out at temperatures up to several hundred degrees, they require significant energy input which typically comes from burning fossil fuels. In order to conserve fossil fuels and reduce CO2 emissions, researchers are now developing photothermal catalysts for hydrogenation reactions, which harness concentrated sunlight to achieve the required reaction temperatures or introduce sunlight into thermal-driven reaction systems to reduce the reaction temperatures. Photothermal catalysts thus need to be able to efficiently absorb sunlight, whilst also being able to drive the desired hydrogenation reaction with high activity and selectivity. In this review, we summarize recent research aimed at the development of photothermal catalysts for CO2/CO hydrogenation and alkene/alkyne/aromatic hydrogenation. Particular emphasis is placed on uncovering the reaction mechanisms at the molecular level, which in turn guides the rational design of photothermal catalysts with better performance.

Several FeS-derived intercalated compounds (C2H8N2)xFeS and Ax(C2H8N2)yFeS (A = Li, Na) were successfully synthesized via a novel ammonothermal method. The powder X-ray diffraction (XRD) measurements reveal that the FeS intercalated samples have the same tetragonal crystal structure as the parent FeS. After intercalation, these three as-synthesized samples do not show superconductor behavior, which is confirmed by the magnetization and the electrical resistivity measurements. (C2H8N2)xFeS exhibits paramagnetic semiconductor behavior, while the newly synthesized Ax(C2H8N2)yFeS (A = Li, Na) shows antiferromagnetic semiconductor behavior. The absence of superconductivity in these FeS-derived compounds should be closely related to the iron vacancies in the FeS layer.

Single-atom catalysts (SACs) are advocated for theoretical 100% atom efficiency and high reactivity. Further breakthroughs in catalytic efficiency beyond the present SACs will rely on upgrading the intrinsic activity of each active site via sophisticated catalyst design, which is undoubtedly challenging. Herein, we report the use of the phase junction confinement principle to construct a TiO2–Pt1–CeO2 ensemble with unprecedented reactivity. The reduction-durable TiO2–Pt1–CeO2 unit enabled weakened CO affinity and extensive lattice oxygen activation, which subsequently led to facilitated O2 activation. Additionally, the TiO2–Pt1–CeO2 interface structure initiated a unique cross-phase oxidation mechanism. The balanced adsorption behaviour, enhanced surface lattice oxygen reactivity, and substantially lowered reaction barrier enabled such a catalyst to realize a great increase in CO oxidation efficiency (300 K) with multiplied specific mass reactivity compared to the impregnated analogue and the pilot Pt1/FeOx catalyst. This work demonstrates a plausible synthesis philosophy and reaction mechanism for SACs that will create a new frontier in reactivity.

Broad-spectrum antibodies can effectively recognize substances with similar structures and have broad application prospects in field rapid detection. In this study, broad-spectrum antibodies (Abs) against organophosphorus pesticides (OPs) were used as sensitive recognition elements, which could effectively recognize most OPs. Gold nanoparticles (AuNPs) have good biocompatibility. It combined with Abs to form a gold-labeled probe (AuNPs–Abs), which enhances the effective binding of antibodies to nanomaterials. Prussian blue (PB) was added to electrodeposition solution to enhance the conductivity, resulting in superior electrochemical performance. The AuNP–Abs–PB composite film was prepared by electrodeposition on the electrode surface to improve the anti-interference ability and stability of the immunosensor. Under the optimal experimental conditions, the immunosensor had a wide detection range (IC20–IC80: 1.82 × 10–3–3.29 × 104 ng/mL) and high sensitivity. Most importantly, it was simple to be prepared and could be used to detect multiple OPs.

In this paper, a dual-signal amplified electrochemical immunosensor for quantitative detection of capsaicinoids in serum was reported, which could be used to study the pharmacological properties of capsaicinoids. To improve the sensitivity of the immunosensor, the glassy carbon electrode was modified with Prussian blue-gold nanocomposites (PB-AuNPs) and thionine (TH). PB-AuNPs provided better electrical conductivity. At the same time, TH enhanced the stability of electron transfer, leading to superior electrochemical performance. Meanwhile, an excellent anti-capsaicinoids antibody (Ab) was used to ensure the sensitivity and specificity of the electrochemical immunosensor. The prepared immunosensor was tested using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under the optimal conditions, the proposed immunosensor displayed a wide linear range from 0.01 to 1000 ng/mL with a detection limit of 0.01 ng/mL and showed good recoveries (85.12–104.25%) and high stability. Additionally, the immunosensor was successfully applied to monitor capsaicinoids in real serum samples.

The CuO–La2O3/ZrO2 catalysts calcined at different temperatures from 500 to 800 °C were studied for the hydrogenation of oxalates to ethylene glycol (EG). Along with the increase of calcination temperatures, the BET surface area, pore volume, and Cu dispersion decreased, whereas the crystallite sizes of Cu species increased. Interestingly, the superior performance such as a 98% selectivity of EG in dimethyl oxalate hydrogenation or a 96.5% selectivity of EG in diethyl oxalate hydrogenation was obtained over the catalyst calcined at 700 °C. Essentially, the surface synergism between Cu species and monoclinic ZrO2 was enhanced by the higher calcination temperature, resulting in the remarkable surface adsorption and activation of H2. Besides, the increase of calcination temperature significantly reduced the surface acidity and basicity, which could effectively suppress the byproduct formation.

The construction of a compact separation layer with selective channel and hydrophilic surface is a promising way to fabricate the composite nanofiltration membranes with both high selectivity and antifouling performance. In this study, a strategy that incorporating zwitterion functionalized titania (ZTi) into membrane surface through facile in-situ sol-gel process is proposed. The titania sol is firstly prepared using tetrabutyl titanate as the precursor and then functionalized by abundant zwitterions based on the chelation reaction. Finally, the ZTi is introduced into polyamide (PA) on the surface of porous polyethersulfone (PES) by in-situ sol-gel method during interfacial polymerization. The physical and chemical structure of the membrane surface is tuned by varying the loading level of titania. Due to the good interfacial compatibility between inorganic ZTi and PA polymer, the optimized PA-ZTi/PES membrane shows a high water flux of 283.5 L m−2 h−1 MPa−1 and a high Na2SO4 rejection ratio of 92.7%, which overcomes the trade-off effect between permeability and selectivity. Moreover, the PA-ZTi/PES series membranes also show superior antifouling performance with flux recovery ratios of 92.9% (against bovine serum albumin) and 95.6% (against humic acid).

The photocatalytic reclamation of the environment requires improved catalysts, as severe charge recombination currently limits their practical application. This study describes a simple synthesis of SnO2−x/Sb2O3 composite by the mechanical milling method. The coupling of SnO2−x possessing oxygen vacancies (OVs) with Sb2O3 is a new approach for obtaining materials with outstanding photocatalytic properties. For the photo-oxidation of isopropanol (IPA) within 5 h, the acetone yield over SnO2−x/Sb2O3 composite with mass ratio of 1:4 was 22.67 and 10.5 times higher than those of SnO2−x and Sb2O3, respectively, and the carbon dioxide output was 13.29 and 7.46 times higher than those of SnO2−x and Sb2O3, respectively. This results showed that the OVs-induced SnO2−x/Sb2O3 heterostructures have a very high IPA photo-oxidation catalytic degradation activity, even after six cycles with no obvious decline. Combination of defect engineering and heterojunction can be a powerful tool for obtaining broad light absorption and high photo-induced charge separation efficiency, which contributes to improving the photocatalytic IPA degradation property.

Enormous efforts have been devoted to the reduction of carbon dioxide (CO2 ) by utilizing various driving forces, such as heat, electricity, and radiation. However, the efficient reduction of CO2 is still challenging because of sluggish kinetics. Recent pioneering studies from several groups, including us, have demonstrated that the coupling of solar energy and thermal energy offers a novel and promising strategy to promote the activity and/or manipulate selectivity in CO2 reduction. Herein, we clarify the definition and principles of coupling solar energy and thermal energy, and comprehensively review the status and prospects of CO2 reduction by coupling solar energy and thermal energy. Catalyst design, reactor configuration, photo-mediated activity/selectivity, and mechanism studies in photo-thermo CO2 reduction will be emphasized. The aim of this Review is to promote understanding towards CO2 activation and provide guidelines for the design of new catalysts for the efficient reduction of CO2 .

Residual bacteria and microleakage in a complicated root canal can often result in reinfection of the periapical tissues. To promote the antibacterial and sealing effects of a root canal filling, core-shell structured CaO/ZnO nanospheres were synthesized using a precipitation method based on a traditional root canal sealer, zinc oxide-eugenol(ZOE). The obtained CaO/ZnO particles had a size of 80–90 nm and a core-shell structure. The film thickness, flow rate, pH, and calcium ion release of the core-shell structured CaO/ZnO nanospheres-eugenol paste were tested. The pH and calcium ion release results showed a slight increase in the prepared nanospheres, with a flow rate of 24.22 mm and a formed film thickness of 30 µm, which are basically consistent with ISO 6876:2001 standards(regarding dental root canal sealing materials). Cytotoxicity tests showed that the cytocompatibility of the CaO/ZnO nanospheres-eugenol paste was much higher than that of the ZOE or iRoot SP groups(P

Promoting the efficient utilization of both pores and heteroatoms remains a highly challenging endeavor, yet is of crucial significance to enhance the specific capacitance and energy density of carbon-based supercapacitors (SCs). Herein, a series of N,P-co-doped polypyrrole-derived carbon nanotubes (Px-ppyNTs) featuring a customized porous structure and doping level and intrinsically endowed with hollow cavities with tunable diameters were designed and synthesized via a strategic engineering approach. Benefiting from their regularly evolved physiochemical architecture, Px-ppyNTs served as a suitable platform to investigate the structure–property relationship between carbon-based materials and electrochemical capacitive behavior. Remarkably, the electrochemical surface area (ECSA) was proven to be critical to the reaction kinetics and resulted in the maximized utilization of both the porous structure and heteroatoms. The optimized ppyNT material with highest utilization of both the SSA (1853 m2 g−1) and inherent heteroatom doping (nitrogen: 7.2 at% and phosphorous: 2.5 at%) exhibited an extremely high specific capacitance of 438 F g−1 in 1.0 M H2SO4 and energy density of 25.3 W h kg−1 in 1.0 M Na2SO4. Furthermore, the calculated electric double layer capacitance (EDLC) contribution was maintained at as high as 203 F g−1 even across a wide scan rate in the range of 5 to 500 mV s−1. This work affords a promising electrode material for SCs and provides new insights into the critical role of ECSA in high-performance carbon-based SCs.

A novel and highly efficient ternary H2SrTa2O7/g-C3N4/Ag3PO4 heterojunction was fabricated via simple impregnation and ion exchange methods with active performance for the degradation of methyl orange (MO) under solar-like irradiation. The optimal result for the binary composite was obtained for a H2SrTa2O7/g-C3N4-60 wt% system. The incorporation of Ag3PO4 led to a further improvement in the photocatalytic performance, as compared to the binary composite and their single components, with values of around 45.18, 44.17 and 38.23 times higher than those of pristine H2SrTa2O7, g-C3N4 and H2SrTa2O7/g-C3N4, respectively. It was found that MO solution (20 mg L−1) could be photo-degraded within 8 min with 50 mg of the H2SrTa2O7/g-C3N4/Ag3PO4 composite. This enhanced photocatalytic behavior can be mainly ascribed to the prominently promoted charge separation efficiency, the matched band-edge positions, the extension of the absorption range and the synergistic effect among H2SrTa2O7, g-C3N4 and Ag3PO4. In addition, X-ray photoelectron spectroscopy and Raman spectroscopy results confirmed a strong interface interaction between H2SrTa2O7, g-C3N4 and Ag3PO4, which greatly promoted the photocatalytic activity due to the improved separation of photoinduced charge carriers. This work presents a plausible mechanism via active species trapping experiments and electron spin resonance measurements demonstrated that photogenerated holes (h+) and superoxide radicals (˙O2−) play a crucial role in the photodegradation reaction under visible light irradiation. Thus, the proposed synthetic method for the fabrication of H2SrTa2O7/g-C3N4/Ag3PO4 with superior photocatalytic activity provides new insights for the design of ternary photocatalysts with an ideal heterojunction and wide spectral response.

Oxygen evolution reaction (OER) electrocatalysts with high efficiency and durability are urgently needed for energy conversion and storage of clean energy. Herein, we report the finding in the development of a hexagonal Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF-H) perovskite as an OER electrocatalyst. Prepared by a sol–gel method, the BSCF-H perovskite displays excellent OER efficiency and stability in a harsh alkaline solution. The overpotential of BSCF-H reveals 360 mV at a current density of 10 mA cm−2 in 0.1 M KOH solution, and its catalytic activity for the OER is even comparable to that of the commercial Ir/C (20%) catalyst. Furthermore, BSCF-H possesses more operational stability with slight current reduction than cubic Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF-C) and RuO2 catalysts. This high activity is explained by a faster charge transfer rate, higher electrochemical surface area and a larger amount of oxygen species (O22−/O−). The Co d-band center and O p-band center of BSCF-H move to the Fermi level, which indicates the better OER performance of BSCF-H. This study demonstrates the new type of hexagonal Co-based perovskite catalyst that could be a low-cost alternative for electrochemical energy technology.

A temperature-controlled ash deposition probe was applied to collect temporally resolved deposit samples in a 100 kW rated down-fired pilot-scale combustor under two atmospheres: (1) air condition ...

Ni/Al2O3 catalysts and bulk Ni nanoparticles, with the average sizes of Ni particles varying from 2.7 nm to 238.0 nm, were synthesized and evaluated in CO2 photoreduction with methane (CRM). It was found that the catalytic activities of the Ni-based catalysts were all increased almost linearly with light intensity in the range of 0–1.07 W cm−2, with the optical properties of Niparticles being regarded to account for the activity enhancement. Wavelength dependent performance study suggested that Ni LSPR dominated for the optical property of smaller Ni nanoparticles whereas interband transition played gradually increased role in improving the activities over larger Ni particles. To the best of our knowledge, it is the first time to study the size-dependent optical properties of Ni nanoparticles, meanwhile, this study offers a foundation to further improve the efficiency of Ni-based catalysts in CO2 utilizations.

Lubricants are an essential component in high-performance mechanical equipment, but traditional lubricants are becoming inadequate for meeting the increasing demands for anti-friction and anti-wear properties and they discharge harmful chemicals to the environment. The purpose of the present study was to explore the use of sepiolite as a novel oil additive to extend the performance of lubricants. Sepiolite nanofibers were first treated by acid followed by a dry air flow, aimed at increasing the pore volume and decreasing the particle size. Then the nanofibers were further modified by an organosilane coupling agent to reduce the surface free energy and to improve the dispersion stability in lubricant. A significant improvement in the performance of the lubricant was achieved by using the modified sepiolite nanofibers as an additive. When the amount of modified sepiolite nanofibers added was 1.5 wt.%, the best performance was demonstrated by the lubricant, showing a viscosity increase at 40°C and 100°C, and an increase in resistance to oxidation. Moreover, the acid value and pour point decreased, and the copper sheet corrosion level dropped to its lowest value.

In this work, intermetallic-free aluminium matrix composites reinforced with TiC and Al2O3 ceramic particles were successfully prepared via an in situ reaction of Al-Ti-C-CuO-La2O3 during self-propagating high-temperature synthesis. The effect of adding the rare earth metal oxide La2O3 was studied by using differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, optical microscopy and Brinell hardness tests. The results showed that La2O3 could promote the wettability of the C and Al melt in the Al-Ti-C-CuO system. The final products of the in situ reaction for the 2.5Al-1Ti-1.2C-0.5CuO-0.005La2O3 system were TiC particles and Al2O3 particles, and the system was free of intermetallic compounds. The prepared aluminium matrix composites were greatly refined with an average grain size of 20.6 μm. The intermetallic-free aluminium matrix composites reinforced with TiC and Al2O3 particles showed up to two times higher Brinell hardness value than the matrix 6063 aluminium alloy.

Ultrathin δ-MnO2 nanosheets were synthesized via in-situ reduction of KMnO4 on graphene oxide using graphene oxide as both reductant and self-sacrificing template. The layered δ-MnO2 nanosheets with a thickness of about 2–4 nm inherit the two-dimensional lamellar morphology of graphene oxide. When used as cathode for aqueous zinc ion batteries, the prepared δ-MnO2 nanosheets exhibit a reversible capacity of 133 mAh/g at a current density of 100 mA/g over 100 cycles and a capacity of 86 mAh/g at 500 mA/g due to the layered structure and ultrathin morphology, which is much better than δ-MnO2 microspheres. The electrochemical and structural investigation indicates a possible mechanism of two-step co-insertion of H+ and Zn2+ into the interlayer of δ-MnO2 during discharge process. It's believed that the unique ultrathin morphology of δ-MnO2 can well facilitate ion diffusion and structure stability during cycling, making ultrathin δ-MnO2 nanosheets a promising cathode in aqueous zinc ion batteries.

The density functional theory was employed to study the effect mechanism of CO₂ on arsenic adsorption by a carbonaceous surface. Geometry optimization and frequency calculation of each structure were calculated by B3LYP-D3/6-31G(d), and the single-point energy of each structure was obtained by B3LYP-D3/6-311+G(d,p). Results show that, when As and As₂O₃ were absorbed on the carbonaceous surface, the adsorption energies were in the range from −526.96 to −463.17 kJ/mol for As and from −24.19 to −11.09 kJ/mol for As₂O₃. It shows that the carbonaceous surface has a chemical adsorption for As and physical absorption for As₂O₃. In the presence of CO₂, the absorption energies decrease, which shows that CO₂ plays a positive impact on As and As₂O₃ adsorption by the carbonaceous surface. By electrostatic potential analysis, it can be concluded that CO₂ absorbed on the carbonaceous surface enhances active sites and, thus, improves the adsorption capacity of the carbonaceous surface for As and As₂O₃. Results show that electrostatic potential is a reliable tool to analyze the strength and orientation of the adsorption reaction, which can be well-predicted and explained by analyzing the magnitude and positions of extrema on the surface. The calculation results clarify the effect of CO₂ on arsenic adsorption by the carbonaceous surface and provide theoretical foundation for the emission and control of arsenic.

Fluorescent copper nanoclusters (CuNCs) have been drawing great research interest because of their fascinating physicochemical properties. However, the low quantum yield (QY) and poor stability of ...

The catalytic performance of Ni-Co bi-component catalysts in CO2 reforming of methane (CRM) under high pressures was studied for obtaining highly stable Ni-based catalysts, which is important for the industrialization of high pressure CRM. A series of 5% (xNiyCo)/SBA-15 catalysts were prepared with a modified co-impregnation method by adding trace amount of β-cyclodextrin (CD) into Ni(NO3)2 impregnation solution. The effects of catalyst compositions (Ni/Co ratio) and the CRM reaction conditions (pressure, gas hourly space velocity, time on stream, etc) on the catalysts stabilities were investigated. The carbon deposition behaviors of the catalysts during the high pressure CRM reaction were disclosed through detailed characterizations of the spent catalysts. The type of coke, instead of the amount of deposited carbon, was proved to be responsible for the deactivation of 5% (xNiyCo)/SBA-15 catalysts during the high pressure reaction. The amount of carbon deposition depended strongly on the Co loading in the bimetallic catalysts. Long-term stability with 100 h TOS at 2.0 MPa and 800 °C was achieved for the optimized 5% (4.5Ni0.5Co)/SBA-15 catalyst and a slow deactivation (decrease in CH4 conversion) was observed. The reaction results with different reaction time over 5% (4.5Ni0.5Co)/SBA-15 at high pressures suggested that the accumulation of carbon deposition took place mainly at the initial stage of the CRM reaction. Moreover, the disorder degree of deposited carbon species and the sintering of metal particles were identified as the primary reasons for the deactivation of the catalysts. Trace Co enriched on Ni-Co surface of 5% (4.5Ni0.5Co)/SBA-15 suppressed Ni aggregation and facilitated the adsorption of co-reactant.

An ideal interface model combining a hematite nanoplate-based photoanode with Au nanoparticles (NPs) is proposed for elucidating the specific role of Au NPs in photoelectrochemical performances. The theoretical and experimental results reveal that Au/Fe2O3 nanoplates can lead to an enhanced localized electric field at the metal–semiconductor interface upon the formation of surface plasmon resonance and hot electrons, which can be injected into the conduction band of the semiconductor, thus improving the efficiency of the generation and separation of electron–hole pairs. As expected, the Au/Fe2O3 nanoplate-based photoelectrode possessed a higher carrier density and a photocurrent of 1.7 mA cm−2 and 3.8 mA cm−2 at 1.23 V and 1.5 V vs. RHE, which are nearly 5 times and 30 times larger than that of the Au/Fe2O3 nanocrystals and pristine Fe2O3 nanoplate-based photoelectrodes, respectively.

A novel polyaniline (PANI)/Sn3O4 heterojunction composed of PANI nanofibers and Sn3O4 nanosheets was fabricated by a facile physical milling technique. Modification of Sn3O4 with a PANI conductive polymer contributes to facilitating interfacial charge transfer efficiency, and thus, significantly enhances the visible-light Rhodamine B (RhB) photo-degradation. Results indicate that PANI/Sn3O4 heterostructures with 10 wt% PANI reached the maximum degradation efficiency (around 97%) for RhB within 5 h, which is 2.27 times higher than that of Sn3O4 alone. This improvement is due to the p–n heterostructure formation in PANI/Sn3O4. Moreover, the outcome of reactive species capturing experiments demonstrated that in PANI/Sn3O4, holes made the largest contribution to RhB degradation under visible light illumination, while hydroxyl radicals showed less significance under the same conditions. In addition, the photocatalytic mechanism was proposed based on evidence from the reactive species test and energy band structure analysis.

There is increasing interest in hot-electron photodetection due to the extended photoresponse well below the semiconductor band edge. However, the photoresponsivity is extremely low and the metallic nanostructures used to excite surface plasmons (SPs) for improved quantum yield are too complex for practical applications. Here, we show that by exciting Tamm plasmons (TPs), a planar device consisting of a thin metal film of 30 nm on a distributed Bragg reflector (DBR) can absorb ∼93% of the incident light, resulting in a high hot-electron generation that is over 34-fold enhanced compared to that of the reference without the DBR. Besides, the electric field increases with the light penetration depth in the metal, leading to hot-electron generation that is strongly concentrated near the Schottky interface. As a result, the photoresponsivity can be over 30 (6) times larger than that of the reference (conventional grating system). Moreover, the planar device exhibits an easily tunable working wavelength from the visible to the near-infrared, sustained performance under oblique incidences, and a multiband photodetection functionality. The proposed strategy avoids the complicated fabrication of the metallic nanostructures, facilitating the compact, large-area, and low-cost photodetection, biosensing, and photocatalysis applications.

Searching for highly active and efficient photocatalysts for photo-induced/photo-assisted reactions remains the most challenging task for solar energy utilization. In previous studies, the search for such materials has mainly focused on precious plasmonic metals (for example, Au, Ag, and Cu) and semiconductor oxides (for example, TiO2 , ZnO, and WO3 ). Herein, we report the application of hexagonal tantalum mononitride (TaN) as an optical support in photocatalytic reactions, which could harness visible light to assist CO2 conversion and decompose organic pollutants. Theoretical studies indicated that the improved electron-hole separation in polar TaN under visible-light illumination was critical for its use in photocatalysis. This study could guide the use of TaN in various photocatalytic reactions and wider optical applications.

The utilization of solar energy is promising in chemical and environmental engineering. Photocatalytic process is applicable for some thermodynamically forbidden reaction such as water splitting and provides a potential approach for efficient solar energy utilization since it could store the abundant solar energy as chemical energy. The study on photocatalysts thrived from the 70s of last century. Among the several types of photocatalysts, semiconductor is one of the most widely studied categories and possesses the potential to be applied industrially. In this review, the types of semiconductors, the modification methods of semiconductors for band gap engineering, and the application of semiconductors for photocatalytic reactions will be summarized, and the challenges and the prospect of semiconductors are proposed, with the aim to provide directions in improving the efficiency and flexibility of semiconductor photocatalysts in design and application for different reactions.

Hybrid effects of nano-silica and graphene oxide on mechanical properties and hydration products of oil well cement have been investigated by means of TEM, TGA, XRD, SEM, MIP and mechanical testing. The results showed the designed hybrid structure was beneficial for SiO2 particles and GO nanosheets to disperse well in alkaline cement. The compressive and flexural strength of cement with hybrid nano-materials of 1.5% NS and 0.03% GO was increased by 43.2% and 42% with 28 days of curing respectively, which was far better than cement with single NS or GO. Graphene oxide and nano-silica have a hybrid effect including better dispersion of nano-materials, higher degree of hydration and pozzolanic reaction, and network structure formation of hydration products, all of which were beneficial to reinforcing the mechanical properties of cement.

The microstructure and mechanical properties of Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe high strength titanium alloy sheets prepared by unidirectional cold rolling and two-step cross cold rolling were investigated. Results showed that the β phase grains were refined significantly by cold rolling followed by solution treatment for a short time. Compared to unidirectional cold rolling, the short time solution treatment after two-step cross rolling could significantly reduce the non-uniformity of the microstructure of the alloy sheets. After aging treatment at 550 °C, the anisotropy of the mechanical properties still existed in the unidirectional rolled sheets, and the tensile strength was highest along the rolling direction. After solution and aging treatment, the anisotropy of the mechanical properties of the two-step cross rolling process sheet was not obvious than unidirectional cold rolling, and alloy had good strength and plasticity matching. Keywords: Cold rolling process, High strength β titanium alloy, Microstructure, Mechanical properties

An annular reactor for direct autothermal reforming of methane was proposed and studied numerically. A one-dimensional heterogeneous model was developed. The effects of feed inlet temperature, initial bed temperature and reactor length were investigated systematically to elucidate the autothermal boundary conditions. Simulation results indicate overall autothermal operation can be achieved if the reactor length exceeds 0.05 m and can be sustained with feed inlet velocity in the range from 0.2 to 5.0 m s−1. Simulation results reveal autothermacity can be kept with air-to-methane ratio of 1.0, which is lower than the theoretical value of 1.5. This is caused by the fact that most of consumed methane was oxidized only. Moreover, drastic bed temperature oscillation was observed in the start-up, which results from the mutual heat transfer between shell and tube in a small range and can be dampened by prolonging reactor length.

A dual-model “on-super off” photoelectrochemical (PEC)/ratiometric electrochemical (EC) biosensor based on signal enhancing and quenching combining three-dimensional (3D) DNA walker strategy was designed for the ultrasensitive and accurate detection of microRNA-224 (miRNA-224). The “signal on” PEC state was achieved by methylene blue labeled hairpin DNA (MB-DNA) for sensitizing CdS QDs. Then numerous transformational ferrocene labeled DNAs (Fc-DNAs) converted by target-induced 3D DNA walker amplification with the help of Ag nanocubes (NCs) label DNA (Ag-DNA) were introduced to open hairpin MB-DNA. Such configuration change would relocate the sensitizer MB and the quencher Fc, whereas energy transfer placed between Ag NCs and CdS QDs, thereby significantly quenching the PEC signal to obtain “super off” state. Meanwhile, these changes resulted in a decreased oxidation peak current of MB (IMB) and an increased that of Fc (IFc). MiRNA-224 was also detected on basis of the dual-signaling EC ratiometric method for complementary PEC detection. Benefiting from different mechanisms and relatively independent signal transduction, this approach not only avoided interference from difficult assembly but also outstandingly increased sensitivity by distance-controllable signal enhancing and quenching strategies. As a result, the detection ranges of 0.1–1000 fM with a low detection limit of 0.019 fM for PEC, and 0.52 to 500 fM with a low detection limit of 0.061 fM for EC, were obtained for miRNA-224, which opens a new avenue for designing numerous elegant biosensors with potential utility in bioanalysis and early disease diagnosis.

The purpose of the study is to explore the application of rapid rehabilitation nursing strategy in the perioperative period of laparoscopic radical prostatectomy for patients with prostate cancer. A total of 120 patients with prostate cancer undergoing laparoscopic radical prostatectomy were randomly divided into two groups, with 60 cases per group. The control group was given routine nursing care, and the experimental group received rapid rehabilitation nursing strategies. The stress hormone (cortisol and norepinephrine) levels, patient satisfaction, length of hospitalization, hospitalization costs, and postoperative complication were compared between the two groups before and after nursing. The serum cortisol and norepinephrine levels in the control group before nursing were similar to those in the experimental group ( P > 0.05 ). The stress hormone levels in the experimental group were lower than those in the control group ( P < 0.05 ). It was found that the experimental group had reduced operation time, less intraoperative blood loss, shortened exhaust time, and hospitalization stay and was earlier to eat and to get out of bed than the control group ( P < 0.05 ). The time for the patients in the experimental group to pull out the drainage tube was significantly shorter than that of the control group ( P < 0.05 ), and the hospitalization costs were fewer than the control group ( P < 0.05 ). The rates of postoperative complications including nausea, vomiting, bleeding, and fever in the experimental group were significantly lower than those in the control group ( P < 0.05 ). In conclusion, the study suggests that rapid rehabilitation nursing strategies can reduce the stress hormone levels, shorten the length of hospitalization, reduce hospitalization costs, reduce postoperative complication rates, and improve patient satisfaction for prostate cancer patients undergoing laparoscopic radical prostatectomy, in support of clinical application.

The thin film solar cells based on Cu2ZnSnS4 (CZTS) compounds have been considered the potentially substitute to Cu(In,Ga)Se2 and CdTe absorbers due to its low cost, earth-abundant and non-toxic components. The present convention efficiency based on Mo/p-CZTS/n-CdS solar cell is far away from the theoritical value, which originated from the interfacial recombination at the Mo/CZTS heterojunction. In our study, we sputtered a 25nm thickness temporary Ge layer between the Mo electrode layer and the CZTS absorbed layer fabricated by spin coating, which could reduce the recombination centers and the Sn-loss. The partial Ge element would diffuse to CZTS which resulted in the formation of kesterite Cu2ZnSnGeS4 (CZTGS) thin films in which the (112) diffraction peaks shifted towards higher angle. The reason is the decreased lattice constant due to the replacement of large Sn atoms by smaller Ge atoms. The field emission scanning electron microscopy (FESEM) showed that the regularity and uniformity have been improved and the voids decreased after inserting Ge layer. The photovoltaic device (ITO/i-ZnO/CdS/CZTGS/Mo) was fabricated. The illuminated J–V characteristics showed that the open circuit voltage (Voc) increased from 513.42 to 620.71 mV, the short circuit current density (Jsc) increased from 11.57 to 12.44 mA, and the efficiency increased from 2.41 to 3.88% after inserting the Ge layer, which attribute to the decreased recombination at the Mo/CZTS contact and the broaden absorption spectra.

A simple U-shaped plastic optical fiber evanescent-wave sensor was fabricated for temperature-independent highly sensitive detection of humidity. The sensing region of the sensor was subjected to five cycles of heating–cooling to improve temperature independence. The effects of the polyimide (PI) coating thickness, number of graphene oxide (GO) coating layers, and alternate PI–GO coating sequence were investigated to optimize sensitivity. The fabricated sensor exhibited high-temperature independence and good sensitivity of 0.17 × 10 − 2 (% relative h u m i d i t y ) − 1 in the temperature range of 10°C to 70°C.

The commercialization of metal-air batteries requires efficient, low-cost, and stable bifunctional electrocatalysts for reversible electrocatalysis of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). The modification of natural coal by heteroatoms such as N and S, or metal oxide species, has been demonstrated to form very promising electrocatalysts for the ORR and OER. However, it remains elusive and underexplored as to how the impurity elements in coal may impact the electrocatalytic properties of coal-derived catalysts. Herein, we explore the influence of the presence of various trace metals that are notable impurities in coal, including Al, Si, Ca, K, Fe, Mg, Co, Mn, Ni, and Cu, on the electrochemical performance of the prepared catalysts. The constructed Zn-air batteries are further shown to be able to power green LED lights for more than 80 h. The charge-discharge polarization curves exhibited excellent and durable rechargeability over 500 (ca. 84 h) continuous cycles. The promotional effect of the trace elements is believed to accrue from a combination of electronic structure modification of the active sites, enhancement of the active site density, and formation of a conductive 3-dimensional hierarchical network of carbon nanotubes.

Two-dimensional (2D) materials with unique structures and fascinating photoelectric properties are typically employed as supporting materials but they have not been mentioned in the context of polarity-reversal-mode photoelectrochemical (PEC) biosensors. Herein, a novel 2D Ti2C MXene-induced photocurrent polarity switching PEC biosensing platform was constructed for the selective and ultrasensitive detection of soluble CD146 (sCD146). Ag2S quantum dots (QDs)-fixed indium-tin oxide slices were used as the photocathode electrodes, and the capture antibody (Ab1) was assembled on the electrode. When the target sCD146 existed, 2D Ti2C MXene labeled with the detection antibody (Ab2) was introduced onto the modified electrode through a typical antigen-antibody sandwich immune reaction, resulting in a polarity switch from a cathodic to an anodic photocurrent. The outstanding optical and electron-transfer capability of the 2D Ti2C MXene made it beneficial to establish a high-performance photocurrent polarity switching PEC biosensor for sCD146 assay, and a linear response range of 0.1–1000 pg/mL with a detection limit of 18 fg/mL was obtained. Furthermore, the developed PEC biosensing strategy possessed excellent anti-interference ability for precluding the false positive or negative signals. The designed 2D Ti2C MXene opens up a new two-dimensional photocurrent-polarity switcher for constructing high-performance PEC biosensors, and the environmentally friendly 2D Ti2C MXene//Ag2S QDs photocurrent polarity switching system could overcome the harmfulness of conventional toxic semiconductors for operators and the environment, offering great potential applications in biological analysis and disease diagnosis.

The effective permeability of a laminated structure is an important parameter related to the practical necessity of coarsening of grid blocks in large scale reservoir simulations. Traditional effective permeability derived under steady state flow conditions can cause great errors in the transient flow process due to the great heterogeneity and anisotropy of laminated formations. To handle this error, the unsteady oil flow in the matrix between hydraulic fractures of a laminated system during an oil depletion process is analyzed in this study. Based on material balance, we present an analytical method for calculating the dynamic effective permeability of the laminated structure considering the cross flow between laminae in the transient flow process. The proposed dynamic effective permeability can be used to conduct coarsening of grid blocks and can be incorporated into numerical models for accurate modeling of transient flow in a laminated structure in the reservoir simulation. It is shown that the simulation results using the proposed effective permeability model match well with those from two-dimensional (2D) simulations. Further, the effects of the horizontal permeability, vertical permeability, thickness of the laminae, and the length of the matrix between fractures are studied.

Continuous homogenous azeotropic distillation (CHAD) and pressure-swing distillation (PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The CHAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus. The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost (TAC). The computational results show that the partially heat integrated pressure-swing distillation (HIPSD) has reduced in the energy cost and TAC by 40.79% and 35.94%, respectively, than the conventional PSD, and has more greatly reduced the energy cost and TAC by 62.61% and 49.26% respectively compared with the CHAD process. The comparison of CHAD process and partially HIPSD process illustrates that the partially HIPSD has more advantages in averting the product pollution, energy saving, and economy.

Continuous peeling of thin chips and flexible devices from a donor to an acceptor is critical for high-efficiency roll-to-roll (R2R) manufacturing of flexible electronics. Here, we propose an R2R conformal peeling technique for the flexible device-on-substrate electronic assembly. First, a mechanical model is established for flexible multilayer structures conformed on curved surface, such as peeling blade, and the corresponding analytical solution of the interfacial shear stress and peeling stress of the adhesive layer is given. Then, the influence of material property and geometrical size of the device (Young’s modulus of different layers and thickness of various layers), the geometric shape of peeling blade (peeling radius and conformal angle), and R2R process parameters (tension and speed of substrate) are analyzed by the theoretical model and experimental test. The peelability law of delaminating devices from the substrate is established for the conformal peeling process. Finally, the design method for a peeling blade is proposed, and the core is to determine the diameter of the peeling blade. It is proofed by the peeling experiment of multilayer electronic devices in the packaging of radio-frequency identification tags.

Plasmonic nanomaterials have wide applications in many fields, such as photocatalysis, solar cell, and new energy generation system. Among them, AgCl–Ag nanomaterials with excellent plasmonic property are getting more and more attention. In this work, AgCl@Ag core–shell nanocubes (AgCl@Ag CS-NCs) with highly uniform morphology and controlled composition have been successfully prepared by the partial reduction of AgCl nanocubes. The morphology, composition, and structure of AgCl@Ag CS-NCs have been investigated systematically. AgCl@Ag CS-NCs with the ratio of AgCl/Ag = 2.7:1 show the optimizational photocatalytic activity for the reduction of representative carcinogenic contaminant (CrVI), which is much higher than that of commercial P25 photocatalyst. The localized surface plasmon resonance and Schottky junction of AgCl@Ag CS-NCs contribute to the high photocatalytic activity for the CrVI photoreduction. After 5 times recyclable catalysis, the high photocatalytic activity of AgCl@Ag CS-NCs can still be maintained well, which demonstrates that AgCl@Ag CS-NCs possess excellent reusability and stability. The high activity and durability make AgCl@Ag CS-NCs to become a promising candidate for the environmental pollution purification under the sunlight irradiation condition.

For nanoparticles active for chemical and energy transformations in static liquid environment, chemistries of surface or near-surface regions of these catalyst nanoparticles in liquid are crucial for fundamentally understanding their catalytic performances at a molecular level. Compared to catalysis at a solid-gas interface, there is very limited information on the surface of these catalyst nanoparticles under a working condition or during catalysis in liquid. Photoelectron spectroscopy is a surface-sensitive technique; however, it is challenging to study the surfaces of catalyst nanoparticles dispersed in static liquid because of the short inelastic mean free path of photoelectrons traveling in liquid. Here, we report a method for tracking the surface of nanoparticles dispersed in static liquid by employing graphene layers as an electron-transparent membrane to separate the static liquid containing a solvent, catalyst nanoparticles, and reactants from the high-vacuum environment of photoelectron spectrometers. The surfaces of Ag nanoparticles dispersed in static liquid sealed in such a graphene membrane liquid cell were successfully characterized using a photoelectron spectrometer equipped with a high vacuum energy analyzer. With this method, the surface of catalyst nanoparticles dispersed in liquid during catalysis at a relatively high temperature up to 150 °C can be tracked with photoelectron spectroscopy.

It is well established that the high dispersion of active catalyst is vital to determine the performance in heterogeneous catalysis after decades of research on nanomaterials. Since the minimum scale for catalytic species is the single-atom metal with isolated metal atoms singly dispersed on, and/or coordinated with the surface atoms of some suitable supports, explosive growth of research on atomically dispersed metal catalysts has emerged especially in frontier heterogeneous catalysis. Such highly dispersed metallic sites (HDMS) imitate the function of site-directed mutagenesis in enzymology, not only maximizing the efficiency of metal atom of interest, but also offering a possibility to achieve the highest catalytic activity and selectivity and make up the gap between heterogeneous and homogeneous catalysis. However, the formidable challenge lies in that with the decreasing size of metal particles or the decreased coordination of metal atoms, the surface free energy of metals is significantly increased, which would lead to serious aggregation of the intended single-atom dispersed catalysts. Therefore, appropriate approaches to construct HDMS and control the HDMS in good homogeneity are importantly necessary to realize the fantastic catalytic activity of HDMS. Problems lie in how to synthesize precisely site-isolated supported metals and how to make sure the metals bond selectively to specific support surface sites. In this review, we aim to assess the above issues via summarizing the key recent progress on HDMS constructing and controlling in terms of the supports and metal precursors engineering, as well as the known interactions between the support and HDMS. We believe that the summary and discussion in the review will lead to a better understanding of HDMS configuration and constructing, and even shed light on novel design for new HDMS based on the discovered interactions between the support and HDMS. We also give a prospect for the future research on HDMS, with emphasizing on the emergence of new fabrication for HDMS with improved catalysts’ thermal stability and possibility for industrial application.

Alkaline direct formate fuel cells (ADFFC) are emerging as a propitious candidate for green energy conversion devices. However, the poor electrocatalytic activity and stability of anodic electrocatalysts are immense challenges for its full-scale commercialization. In the current work, Pt–Ag alloy nanoballoon nanoassemblies (ANBNSs) were easily synthesized by the galvanic replacement reaction between three-dimensionally multibranched Ag nanoflowers and K2PtCl4. Electrochemical results exhibit that Pt–Ag ANBNSs have a nearly 19.3-fold activity enhancement for the formate oxidation reaction (FOR) over commercial Pt nanoparticles in alkaline media, as well as a higher resistance to CO poisoning and excellent durability for the FOR. This work demonstrates that Pt–Ag ANBNSs are indeed highly promising active and durable electrocatalysts for the FOR due to the integration of geometric/electronic effects and porous architecture.

A novel Sb doped SnO2 decorated porous g-C3N4 nanosheet composite photocatalyst, which can be applied in photocatalytic reactions for CO2 reduction and gaseous iso-isopropanol (IPA) oxidation under visible light irradiation, is designed and synthesized. Results demonstrate that the intimate interfacial contact and heterojunction interaction between g-C3N4 and Sb doped SnO2 can significantly boost the photocatalytic efficiencies compared with individual g-C3N4 and Sb doped SnO2 due to the effective separation of photo-generated charge carriers.