Mechanism Of Efficiency Enhancement Research Articles

Study on Aerodynamic Performance of Propeller with Tip Winglet

Based on the Reynolds-averaged Navier-Stokes governing equations and the unstructured grid rotating/stationary sliding surface technology, this paper studies the aerodynamic layout and efficiency enhancement mechanism of the near-space propeller blade tip winglet configuration. First, the feasibility of the configuration is verified by comparing and analyzing different lift propeller layout schemes. Secondly, the aerodynamic layout design of the blade tip winglet propeller is studied by changing the winglet inclination angle and length parameter indicators. Finally, the ANSYS simulation analysis is used to calculate the influence of the winglet design on the propeller velocity vector distribution, blade pressure and propeller aerodynamic efficiency, and the performance influence law of the basic parameters is preliminarily established, and the overall design scheme of the new blade tip winglet propeller design is completed. The study shows that the blade tip winglet propeller layout is a reasonable and feasible technical approach to improve the aerodynamic efficiency in the near-space working environment, and it has a certain reference role in the development of new configuration propeller aircraft.

Metal-organic framework (MOF) integrated Ti3C2 MXene composites for CO2 reduction and hydrogen production applications: a review on recent advances and future perspectives.

Titanium carbide (Ti3C2) MXenes due to their structural and optical characteristics rapidly emerged as the preferred material, particularly in catalysis and energy applications. On the other hand, because of its enormous surface/volume ratio and porosity, Metal-organic Frameworks (MOFs) show promise in several areas, including catalysis, delivery, and storage. The potential to increase the applicability of these magic compounds might be achieved by taking advantage of the inherent flexibility in design and synthesis, and optical characteristics of MXenes. Thus, coupling MOF with Ti3C2 MXenes to construct hybrid composites is considered promising in a variety of applications, including energy conversion and storage. This paper presents a systematic discussion of current developments in Ti3C2 MXenes/MOF composites for photocatalytic reduction of CO2, and production of hydrogen through water splitting. Initially, the overview and characteristics of MXenes and MOFs are independently discussed and then a detailed investigation of efficiency enhancement is examined. Different strategies such as engineering aspects, construction of binary and ternary composites and their efficiency enhancement mechanism are deliberated. Finally, different strategies to explore further in various other applications are suggested. Although Ti3C2 MXenes/MOF composites have not yet been thoroughly investigated, they are potential photocatalysts for the production of solar fuel and ought to be looked into further for a range of applications.

Study on Efficiency-Enhancing Mechanism for SB TWT by Evenly Distributing SWS Impedance

Study on Efficiency-Enhancing Mechanism for SB TWT by Evenly Distributing SWS Impedance

Construction of −SO3H and Zn2+ dual active sites over silica aerogel for NH3 adsorption: Collaborative efficiency enhancement performance and mechanism

The inherently corrosive and explosive nature of ammonia presents significant environmental and health hazards, highlighting the critical challenge of developing high-efficiency adsorbents for its removal. In this study, a dual-active site-modified silica aerogel containing Brønsted acid (−SO3H) and metal ions (Zn2+) was synthesized using both sol–gel and physical deposition methods for ammonia adsorbent. The optimally modified 3SO3H@SA aerogel displayed an adsorption capacity of 2.38 mmol·g−1. The incorporation of nanosized Zn2+ active sites boosted this capacity to 5.14 mmol·g−1, making a 210 % enhancement over the unmodified aerogel. Kinetic and NH3-TPD analyses underscored the increasing importance of chemical adsorption with the rise in active site abundance. Quantum chemical simulations elucidated the molecular-level adsorption mechanism, corroborating experimental results. The synergy between metal ions and acidic functionalities in this dual-modified aerogel demonstrates its efficacy and potential in NH3 adsorption applications, offering convincing insights for the development of high-capacity ammonia adsorbents.

FRET‐Amplified Singlet Oxygen Generation by Nanocomposites Comprising Ternary AgInS2/ZnS Quantum Dots and Molecular Photosensitizers

AbstractAntibacterial photodynamic therapy (a‐PDT) has emerged as a promising non‐invasive therapeutic modality that utilizes the combination of a photosensitive agent, molecular oxygen, and excitation light to generate reactive oxygen species (ROS), demonstrating remarkable activity against multidrug‐resistant bacterial infections. However, the effective use of conventional photosensitizers is significantly limited by a number of their shortcomings, namely, poor water solubility and low selectivity. Herein, we present a novel biocompatible water‐soluble nanocomposite based on hydrophobic tetraphenylporphyrin (TPP) molecules and hydrophilic ternary AgInS2/ZnS quantum dots incorporated into a chitosan matrix as an improved photosensitizer for a‐PDT. We demonstrated that TPP molecules could be successfully transferred into chitosan solution while remaining primarily in the form of monomers, which are capable of singlet oxygen generation. We performed a detailed analysis of the Förster resonance energy transfer (FRET) between quantum dots and TPP molecules within the nanocomposite and proposed the mechanism of the singlet oxygen efficiency enhancement via FRET.

How does digital transformation affect the ESG performance of Chinese manufacturing state-owned enterprises?-Based on the mediating mechanism of dynamic capabilities and the moderating mechanism of the institutional environment.

Against the background of sustainable development policies, the ESG performance of Chinese manufacturing enterprises is still generally poor. As the leading enterprises in the manufacturing industry, state-owned enterprises should take the lead in responding to the national call for sustainable development and actively explore the path to improve their ESG performance. This study aims to explore whether and how state-owned manufacturing enterprises can improve their poor ESG performance through digital transformation in the digital economy. This study takes Shanghai and Shenzhen A-share state-owned listed manufacturing enterprises as the research sample and constructs an unbalanced panel. OLS regression analysis is used to empirically test the impact of digital transformation on the ESG performance of the sample firms. Further attempts are made to discuss the influence mechanism of digital transformation from the perspectives of dynamic capabilities and the institutional environment through stepwise and hierarchical regression methods, respectively. The study shows that, firstly, digital transformation is an important influencing factor in promoting the improvement of enterprises' ESG performance, and at the same time, there are significant structural differences in this influence. Second, under the dynamic capability perspective, digital transformation can improve corporate ESG performance through an absorptive feedback mechanism, matching response mechanism, and innovation efficiency enhancement mechanism. Third, from the perspective of the institutional environment, the informal system has a significant positive moderating effect on the relationship between digital transformation and ESG performance, i.e., the informal system and digital transformation have a synergistic governance effect on corporate ESG performance. The moderating effect of the formal institutional environment on digital transformation and ESG performance is not significant. The findings of the study clarify the controversy over the relationship between digital transformation and ESG performance of manufacturing state-owned enterprises and enrich the research on the influencing factors of corporate ESG performance. It also provides a theoretical foundation and empirical evidence for manufacturing SOEs to improve ESG performance and lead to sustainable development.

Nanofluids as a coolant for polymer electrolyte membrane fuel cells: Recent trends, challenges, and future perspectives

In this comprehensive review, we critically examine the application of nanofluids as coolants in PEMFCs, explicitly focusing on elucidating their thermal efficiency enhancement mechanisms. In addition to the existing research, the significant areas critically reviewed include the influence of nanoparticle size and concentration, surface modification techniques, characterization methods, nanofluid stability under different conditions, nanofluid behavior in various flow regimes, and the impact of nanofluids on system performance and efficiency. A meticulous analysis of the most recent studies involving single nanofluids (Al2O3, SiO2, TiO2, ZnO, BN) and hybrid nanofluids (CuFeAl, Al2O3:SiO2, Bio glycol+Al2O3:SiO2, TiO2:SiO2) underscores their potential to revolutionize PEMFC cooling systems. Findings reveal that nanofluids exhibit remarkable enhancements in heat transfer, offering a 20–27% reduction in radiator size compared to traditional coolants. The science underpinning this enhancement is multifaceted, characterized by self-deionization phenomena, nanoparticle dispersion stability via Brownian motion, and unprecedented inter-atomic interactions. Notably, nanofluids effectively eliminate particle sedimentation and coagulation, ensuring sustained heat transfer performance over extended operational periods. However, several challenges are observed, such as the limited exploration of electrical conductivity, which occurred because of the correlation between the net-charge influence of the suspended particle and electrical double layer (EDL) behavior. Furthermore, understanding and utilizing smart nanofluids and nanobubbles demand rigorous investigation for optimal cooling strategies. Future research should focus on standardizing nanofluid synthesis and characterization protocols, elucidating the underlying heat transfer mechanisms, addressing cost and scalability issues, and ensuring nanofluids’ durability in PEMFCs. The review’s timeliness lies in its relevance to the current advancements and challenges in the field, offering valuable insights for researchers and practitioners working in the thermal management of PEMFC.

Secure and Efficient UAV Tracking in Space-Air-Ground Integrated Network

With the development of 5 G and other communication techniques, the space-air-ground integrated network (SAGIN) is regarded as a promising solution to provide wide-range, cost-effective, and real-time wireless access. Unmanned Aerial Vehicle (UAV) Tracking plays a crucial role in guaranteeing the performance of SAGIN. However, UAV tracking still faces a series of challenges in the real-world deployment, especially in the case of the presence of malicious attackers, who may launch a series of attacks ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">e.g.</i> , message spoofing attack, routing misbehavior attack) to disrupt the systems. In this study, to enhance the security and efficiency of SAGIN when conducting object tracking, we propose a novel and secure object tracking system named <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SecTracker</small> to overcome the emerging security problems in the SAGIN. Focusing on the unmanned aerial vehicle (UAV) tracking, we design the Local Voting based Detection Module to defend the message spoofing attack and implement the Routing Evidence based Detection Module to defend the routing misbehavior attack. Besides, efficiency enhancement mechanisms ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e.</i> , probabilistic detection algorithm and game theory based algorithm) are proposed in this paper to improve the efficiency of <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SecTracker</small> . Considering the above-mentioned attacks, the overall tracking accuracy is improved from 88.16% in existing schemes to 96.64% in <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SecTracker</small> , which demonstrates the effectiveness of the proposed system.

Enhanced photothermal conversion performance of MWCNT/SiC hybrid aqueous nanofluids in direct absorption solar collectors

Nanofluids containing light-absorbing nanoparticles are potential alternative working fluids in solar collectors. In this work, a novel hybrid aqueous nanofluid containing multi-walled carbon nanotubes (MWCNTs) and SiC nanoparticles is prepared to improve the photothermal conversion ability of working fluids. The hybrid nanofluid overcomes the disadvantages of one-component nanofluids and achieves good solar absorption on the merit of the complementary optical property of MWCNTs and SiC nanoparticles. The prepared nanofluids show excellent stability due to the hydroxyl functionalization of MWCNTs, and the thermal conductivity of hybrid nanofluids is also enhanced. A high photothermal conversion efficiency of 64.7 % is achieved by the hybrid nanofluid after 1-hour irradiation, which is significantly higher than that of the reported MWCNT-based aqueous nanofluids in the literature. Meanwhile, the mechanism of efficiency enhancement in MWCNT/SiC hybrid nanofluids is analyzed. This study promotes the application of MWCNT/SiC hybrid nanofluids as light-absorbing working fluids in solar collectors.

Quantum-Coherence-Enhanced Hot-Electron Injection under Modal Strong Coupling.

Modal strong coupling between localized surface plasmon resonance and a Fabry-Pérot nanocavity has been studied to improve the quantum efficiency of artificial photosynthesis. In this research, we employed Au nanodisk/titanium dioxide/Au film modal strong coupling structures to investigate the mechanism of quantum efficiency enhancement. We found that the quantum coherence within the structures enhances the apparent quantum efficiency of the hot-electron injection from the Au nanodisks to the titanium dioxide layer. Under near-field mapping using photoemission electron microscopy, the existence of quantum coherence was directly observed. Furthermore, the coherence area was quantitatively evaluated by analyzing the relationship between the splitting energy and the particle number density of the Au nanodisks. This quantum-coherence-enhanced hot-electron injection is supported by our theoretical model. Based on these results, applying quantum coherence to photochemical reaction systems is expected to effectively enhance reaction efficiencies.

An Enhanced Adaptive Large Neighborhood Search for Unrelated Parallel Machine Scheduling With Sequence Dependent Setup Times

The unrelated parallel machine scheduling problem with sequence dependent setup times (UPMSP-SDST) addressed in this study refers to allocating jobs among a given number of machines and determining their processing sequence on each machine, to minimize the makespan (i.e., the maximum completion time). To deal with large-scale UPMSP-SDST with higher efficiency, this study presents an enhanced adaptive large neighborhood search (EALNS) algorithm with various destroy and repair operators and an efficiency-enhancement mechanism. The efficiency-enhancement mechanism is mainly composed of a simplified calculation method and a hierarchical comparison mechanism, which are applied to improve the implementation process of the greedy-based operators. The simplified calculation method obtains a new makespan by an incremental or decremental transformation, to avoid reluctant calculations. The hierarchical mechanism refines the comparison of different removal or insertion strategies of the operators, thereby arresting high-quality solutions with more metrics. The proposed algorithm is tested on 1640 instances, and numerical results demonstrate the superior performance of the EALNS over the existing methods, especially for large-scale problems. Notably, 834 instances ’ best-known solutions are updated from this study. In addition, deep analysis of the impact of the distribution of setup time on the performance of the algorithm is provided, which further verifies the potential wide applicability of the proposed EALNS.

Efficiency enhancement mechanism of piezoelectric effect in long wavelength InGaN-based LED.

Improving the luminescence efficiency of InGaN-based long wavelength LEDs for use in micro-LED full-colour displays remains a huge challenge. The strain-induced piezoelectric effect is an effective measure for modulating the carrier redistribution at the InGaN/GaN heterointerfaces. Our theoretical results reveal that the hole injection is significantly improved by the diminution of the valence band offset (VBO) of the InGaN/GaN heterointerfaces along the [0001] direction, and inversely, the VBO increases along the [0001] direction. The energy band structures showed that the tensile strain of the GaN film grown on a silicon (Si) substrate could weaken the internal electric field of the InGaN well layer leading to a flattening of the energy band, which increases the overlap of electron and hole wave functions. In addition, the strain-induced piezoelectric polarisation of the InGaN layer on the Si substrate generates opposite sheet-bound charges at the heterointerfaces, which causes a reduction in the depletion region of the InGaN/GaN quantum wells (QWs). A systematic analysis illustrates that the control of the piezoelectric polarisation of the InGaN QW layer is available improve the internal quantum efficiency of the InGaN-based LEDs.

Discussion on the sweep efficiency of hybrid steam−chemical process in heavy oil reservoirs: An experimental study

Non-condensable gas (NCG), foam and surfactant are the three commonly-used additives in hybrid steam−chemical processes for heavy oil reservoirs. Their application can effectively control the steam injection profile and increase the sweep efficiency. In this paper, the methods of microscale visualized experiment and macroscale 3D experiment are applied to systematically evaluate the areal and vertical sweep efficiencies of different hybrid steam−chemical processes. First, a series of static tests are performed to evaluate the effect of different additives on heavy oil properties. Then, by a series of tests on the microscale visualized model, the areal sweep efficiencies of a baseline steam flooding process and different follow-up hybrid EOR processes are obtained from the collected 2D images. Specifically, they include the hybrid steam–N2 process, hybrid steam–N2/foam process, hybrid steam−surfactant process and hybrid steam–N2/foam/surfactant process (N2/foam slug first and steam−surfactant co-injection then). From the results of static tests and visualized micromodels, the pore scale EOR mechanisms and the difference between them can be discussed. For the vertical sweep efficiencies, a macroscale 3D experiment of steam flooding process and a follow-up hybrid EOR process is conducted. Thereafter, combing the macroscale 3D experiment and laboratory-scaled numerical simulation, the vertical and overall sweep efficiencies of different hybrid steam−chemical processes are evaluated. Results indicate that compared with a steam flooding process, the areal sweep efficiency of a hybrid steam–N2 process is lower. It is caused by the high mobility ratio in a steam–N2–heavy oil system. By contrast, the enhancement of sweep efficiency by a hybrid steam–N2/foam/surfactant process is the highest. It is because of the high resistance capacity of NCG foam system and the performance of surfactant. Specifically, a surfactant can interact with the oil film in chief zone and reduce the interfacial energy, and thus the oil droplets/films formed during steam injection stage are unlocked. For NCG foam, it can plug the chief steam flow zone and thus the subsequent injected steam is re-directed. Simultaneously, from the collected 2D images, it is also observed that the reservoir microscopic heterogeneity can have an important effect on their sweep efficiencies. From the 3D experiment and laboratory-scaled numerical simulation, it is found that a N2/foam slug can increase the thermal front angle by about 15° and increase the vertical sweep efficiency by about 26%. Among the four processes, a multiple hybrid EOR process (steam–N2/foam/surfactant process) is recommended than the other ones. This paper provides a novel method to systematically evaluate the sweep efficiency of hybrid steam–chemical process and some new insights on the mechanisms of sweep efficiency enhancement are also addressed. It can benefit the expansion of hybrid steam−chemical processes in the post steamed heavy oil reservoirs.

Stimulated triplet–triplet fusion by carrier trap-detrap mechanism in organic light-emitting diodes

Triplet–triplet fusion (TTF) has been an efficiency-enhancing mechanism in fluorescent organic light-emitting diodes (OLEDs) caused by the collision of two triplet excitons. However, achieving a high TTF ratio in fluorescent OLEDs has been difficult despite device strategies to maximize the triplet exciton density within a narrow recombination zone near the electron blocking layer (EBL) due to charge imbalance and hole accumulation between the TTF type emitter and EBL. Based on a trap-detrap mechanism, we were able to realize an improved TTF ratio and reduce hole accumulation by adding a TTF-assisting material (TTF-AM) in the TTF emitter. The TTF-AM served as the hole transport channel, triggering hole trap and detrap while improving the hole transport character of the emitting layer. Through the process of hole detrapping, the improved hole transport properties balanced carriers and generated more triplet excitons in order to activate the TTF mechanism from low to high current density ranges. By adjusting the TTF-AM, the TTF ratio of the anthracene-based emitter was increased from 5.5/20.1% to 13.4/25.5% (low/high current density), thereby resulting in more than doubled external quantum efficiency at low current density.

Methyl silicate promotes the oxidative degradation of bisphenol A by permanganate: Efficiency enhancement mechanism and solid-liquid separation characteristics

Permanganate (Mn (VII)) is an environmentally-friendly mild oxidant in the field of advanced oxidation treatment, however, manganese colloids are produced as byproducts, which is difficult to separate from water, resulting in secondary pollution. This study used potassium methyl silicates (PMS) as surface modifiers to improve the aggregation of colloidal particles by increasing the hydrophobicity of the colloidal surface, and then explored the oxidation of bisphenol A (BPA) by Mn (VII) under the influence of potassium methyl silicate and the solid-liquid separation performance of the reaction system. The results showed that PMS and sodium silicate (SS) substantially enhanced the degradation of BPA by Mn (VII), and the promotion effect of potassium methyl silicate was greater than that of sodium silicate. PMS provided not only enough adsorption sites for MnO2 colloidal particles formed in the reaction process, but also reaction space for Mn (VII) to catalyze the oxidation of BPA. PMS combined with the hydroxyl group of MnO2 through hydrogen bonds and forms hydrophobic PMS-MnO2 complexes which accelerated sedimentation by polycondensation. The strong adsorption ability of in situ formed MnO2 colloids also accelerated the deposition of PMS-MnO2 complex. This study solved the low efficiency problem of Mn (VII) oxidation degradation of organic pollutants and difficult separation of manganese containing colloids and provided a new strategy for the efficient utilization of Mn (VII).

Application of patterned sapphire substrate for III-nitride light-emitting diodes.

Recent decades have witnessed flourishing prosperity of III-nitride emitters in solid-state lighting and high-resolution displays. As one of the widely used substrates, sapphire shows superiority for heteroepitaxial growth of III-nitride light-emitting diode (LED) structure, due to the advantages of stability, low cost, high mechanical strength, as well as mature fabrication technology. However, realization of efficient LEDs grown on sapphire substrate is impeded by high density of defects in epilayers and low light extraction efficiency. The emergence of patterned sapphire substrate (PSS) turns out to be a promising and effective technology to overcome these problems and enhance the LED performances. In this review, we first introduce the background and recent advances of PSS applied in III-nitride visible and ultraviolet LEDs are. Then, we summarize the fabrication methods of PSS, together with novel methods to define nanometre-scale patterned structures. We further demonstrate the effect of PSS that contributes to reduce the threading dislocation density (TDD) of epilayers in detail. Meanwhile, mechanism of light extraction efficiency enhancement by adopting PSS is presented based on numerical analysis. Next, we explore the influence of PSS structural parameters (e.g. pattern size, pattern shape and aspect ratio) on LED performances, spanning from visible to deep ultraviolet UV emission region. Finally, challenges and potential prospects in PSS for future LED development are proposed and forecasted as well.

Computational design of passivants for CdTe grain boundaries

CdTe is the second most-widely deployed photovoltaic (PV) material due to its high efficiency and low manufacturing costs. Currently, polycrystalline CdTe (poly-CdTe) has a record efficiency of ~22%, which is still well below the theoretical limit (~30%). Polycrystalline CdTe films that have incorporated Cl or Se show higher efficiency, possibly due to the segregation of these ions to the grain boundaries (GBs), where they may passivate the dangling bonds. However, the efficiency enhancement mechanisms of passivants in CdTe GBs, and the feasibility of employing alternative passivants, have not been well explored. Here, we present a systematic computational study of CdTe GBs with potential passivants, namely S, P, As, Se, and Sb on Te sites, and Na, Mg, Al, Sc, Cu, and Zn on Cd sites. Density functional theory (DFT) calculations were performed on GB dislocation core structures derived from scanning transmission electron microscopy (STEM) images of a model GB (bicrystal). We computed the segregation thermodynamics, electronic density of states, and charge variations near doped CdTe GBs. We find that segregation of impurities to GBs is thermodynamically favorable. For a Te-terminated core, Se, S, and P on Te sites effectively reduce midgap states. For both Cd- and Te- terminated dislocation cores, Sc and Al reduce midgap states when substituted for Cd atoms. The greatest improvement was achieved with co-doping, i.e. simultaneously substituting Te with Se and substituting Cd with Cu or Al. The elimination of midgap states is predicted to increase the photovoltaic efficiency of CdTe by reducing the recombination at grain boundaries. • CdTe solar cell efficiency depends highly on grain boundary properties. • Large scale first principles computational study was performed on realistic grain boundary models. • For a Te-terminated core, Se, S, P, and As on Te sites effectively reduce midgap states and improve efficiency. • For both Cd- and Te- terminated dislocation cores, Sc and Al on Cd sites reduce the midgap states and improve efficiency.

Efficiency enhancement in thin-film silicon solar cells by plasmonic nanodiscs array

Plasmonic nanoparticles are promising ways for the efficiency enhancement of thin-film solar cells. We have taken into account the bare silicon wafer and the embedded thin-film silicon solar cells with Au nanodiscs array. We study these geometries of thin-film silicon solar cells and find the effect of Au nanoparticles on light transmission and reflection spectrum, power absorption, generation rate, power electric, and short-circuit current density; and for this, we have used finite difference time domain, FDTD software. We also consider the near-field electric intensity in the vicinity of nanoparticles with different sizes, which are known as a solar cells efficiency enhancement mechanism. Our study can be useful for new perspectives for antireflection coating applications and light management in silicon solar cells.

High-performance acetone gas sensor based on Pt–Zn2SnO4 hollow octahedra for diabetic diagnosis

Acetone in exhaled breath can be used as a biomarker for diabetes diagnosis, but its concentration is extremely low. Thus, a gas sensor with high sensitivity and a low detection limit (sub-ppm level) is vital in practical application. Here, ultrafine Pt nanoparticles were prepared and used to decorate the surface of Zn2SnO4 (ZTO) hollow octahedra for enhanced acetone gas-sensing performance towards breath analysis. The Pt nanoparticles were prepared by a simple wet chemical method, whereas the decoration on the surface of ZTO was conducted by mixing different amounts of Pt nanoparticles. The synergistic effect of the high catalytic activity of Pt nanoparticles and the large surface area of ZTO hollow octahedra endowed the fabricated sensor with excellent acetone-sensing performance at the optimum temperature of 350 °C. Compared with pristine ZTO, the 1 wt% Pt–ZTO device showed the best acetone sensing behaviour at 350 °C with an excellent selectivity, repeatability, and stability. It was able to detect acetone at ppb level, which was satisfactory for breath analysis in diabetes diagnosis. Notably, the 1 wt% Pt–ZTO sensor exhibited a 36.9-fold enhancement in response to acetone compared with the pristine ZTO. Moreover, the effect of Pt decoration on gas-sensing behaviours and the gas-sensing efficiency enhancement mechanism of ZTO hollow octahedra were discussed.

Experimental study on the removal of PM2.5 using modified carbon steel collectors with hydrophilic properties in wet ESPs

Along with the increasingly stringent dust emission concentration standards for the thermal power plants and the challenge of market competition, wet electrostatic precipitators (ESPs) have been widely used as terminal equipment for the flue gas treatment. The wet ESPs pilot test platform using the modified carbon steel collectors with hydrophilic properties was established in this paper and the experimental research on PM2.5 removal characteristics were carried out. The mechanism of the particles removal efficiency enhancement by water film on the surface of modified collectors was studied. The effect of gas temperature, residence time, working voltage, inlet concentration and flushing water flowrate on the particles removal efficiency was investigated. The results indicated that the fibrous layer over the surface of the modified collectors could reduce the effect of the airflow recoil and the electromigration resistance of particles. The surface of the modified collectors could also maintain a uniform and stable water film with a lower amount of water consumption. The water film could restrain the back corona and the re-entrainment of dust. And the evaporation of water film increased the humidity of the flue gas, meanwhile, the particles charge capacity and electromigration velocity increased. Those all could improve the particles removal efficiency. The particles removal efficiency increased with the increase of the flue gas residence time and the applied voltage, but the particles removal efficiency improved less with the increase of the particles inlet concentration and flushing water flow rate after maintaining uniform and stable water film. The modified rigid collector provided high removal efficiency for particles with diameters of 0.04～0.48 μm under lower energy and water consumption. Implications: The wet electrostatic precipitators (ESPs) have been widely used as terminal equipment of the flue gas treatment to purify the flue gas deeply. The surface of the modified carbon steel collectors with hydrophilic properties could maintain a uniform and stable water film with a lower amount of water consumption. The evaporation of water film improved the particle charge capacity and electromigration velocity. The wet ESPs using the modified rigid collector exhibited significantly higher removal efficiency of particles than using the conventional rigid collector especially to the particles with diameter of 0.04～0.48 μm.