Additional Energy Supply Research Articles

De novo Cu-MOF@CNS nanocomposite coated on a cotton fibrils framework for sustainable solar-driven desalination.

Environmental researchers are extremely concerned about addressing the declining availability of drinking water, which is a critical issue in many nations. Solar-driven desalination is an emerging and pioneering renewable approach to reduce potable water scarcity that is suitable for remote locations, developing countries, and disaster zones as it does not require additional energy supply. However, there are still issues with the scalable preparation of photothermal materials, such as achieving low cost and widening the assortment of useful applications. Conventional carbon- and metal-based absorbers are intricate and fragile, which make them difficult to install and transport in places with minimal infrastructure. Thus, a universal process for creating adaptable solar evaporators is sorely required. Herein, we have come up with a holistic approach using a solar absorber (GJ-01(Cal)) derived from a Cu-MOF (HKUST-1) and carbon nanosheets (CNSs) for generating potable water from saline water using solar radiation. The as-synthesized material provides high-performance photothermal water evaporation when illuminated under solar irradiation at the air-water interface. Moreover, its porous structure, high photothermal conversion efficiency, rapid water flow, and heat insulation make it appropriate for saline water desalination. CNS play a pivotal role in improving the photothermal features of the solar absorber (GJ-01(Cal)) in terms of conjugation to promote Cu(0) species and pyrrolic nitrogen (P-N) amplification and thereby enrich the p-type nature of the absorber's triphasic configuration. With these photothermal factors, the localised surface plasmon resonance (LSPR) of electrons increases and achieves high solar spectrum absorption. The GJ-01(Cal) was further coated on porous cotton fibrils (CF) that regulate photothermal interfacial evaporation (PTIE) by allowing water transportation via capillary action. This assemblage of the nanocomposite on CF efficiently evaporates water at a higher surface temperature of ∼47 °C under one solar illumination, achieving 4.23 kg m-2 h-1 of evaporation flux and 96.5% light-to-heat conversion efficiency. Interestingly, the GJ-01(Cal) coated over CF can be recycled at least 10 times. Additionally, it offers scalable production for higher photothermal efficiency with a flexible substrate as a solar evaporator and is beneficial for society paving new horizons towards a sustainable environment.

Submerged nanoporous anodized alumina structure for solar-powered desalination.

Development of nanoporous structures utilizing a single step of anodization technique is well recognized as a cost-effective and straightforward approach for several applications. In the current work, anodized alumina was developed with nanoporous structure by utilizing oxalic acid as an electrolyte with a continuous voltage of 40 V. The formed nanoporous structure was subjected to desalination application because of its high absorbance of broadband solar spectrum energy. The desalination setup consists of two solar stills namely conventional and modified. The developed structure is placed in the modified still to examine its performance. It was observed that the structure distributing heat to surrounding water by absorbing photon energy from the sun through the nanopores and giving an efficient pathway to the water vapours for developing effective desalination. The nanoporous structure having ~ 45 nm average diameter. Furthermore, the band gap energy of nanoporous structure was found to be ~ 2.5 eV (absorption spectrum fitting) and ~ 2.8 eV (Tauc plot). The nanoporous structure possess the visible light spectra in solar region which helps the band gaps of nanoporous structure to provide an additional supply of energy for generating more water to evaporate. Moreover, the Urbach energy of the structure is 0.5 eV which reveals less defects in the modified still. The overall distillate yield of modified still was increased to 21% in contrast to conventional. Water quality analysis was also carried out before and after the desalination experiments, and the results were within acceptable limits set by World Health Organization (WHO).

Durable Self-Cleaning Radiative Cooling Coatings for Building Energy Efficiency.

Passive daytime radiative cooling (PDRC) is an energy-saving technology without an additional energy supply or environmental pollution. At present, most PDRC coatings for buildings are only aiming at high solar reflectivity (RS) and high mid-infrared emissivity (EMIR) while ignoring practicalities such as adhesion strength, scalability, and durability. In this work, modified calcined kaolin/(ethylene trifluorochloroethylene copolymer-polydimethylsiloxane) (MK/(FEVE-PDMS)) coating with super practicability is prepared by using MK as a filler, FEVE as an adhesive, and PDMS as a hydrophobic modifier. The RS and EMIR of the coating are 92.5 and 94.6%, respectively. The MK/(FEVE-PDMS) coating exhibits superhydrophobicity, with an advancing contact angle (ACA) of 160.2° and a hysteresis contact angle of 7.3°. At an average solar irradiance of 742.78 W m-2, the coating achieved a temperature drop of 13.12 °C (shielded with PE film) and 3.09 °C (without shielding), respectively, relative to the environment. The coating adheres firmly to the substrate with an adhesion strength of class 2. The superhydrophobicity of the coating provides excellent durability and ease of repair, which can resist UV aging and mechanical damage. The durable superhydrophobicity gives the coating long-term stability in PDRC performance. Additionally, the cheap raw materials and the preparation process, consistent with the production of existing paints, show excellent scalability. Moreover, the energy consumption simulation results show that the energy saving ratio of the coating is more than 10% in the densely populated Yangtze River Delta and Pearl River Delta. The durable self-cleaning radiative coating developed in this work has potential application prospects in areas where the demand for cooling in summer is large and the demand for heating in winter is small.

Coupling Mechanism of Multiple-Thermal-Fluid Multi-Cycle Stimulation in Ultra-Heavy-Oil Reservoirs

Multiple-thermal-fluid (MTF) stimulation technology has been successfully applied in heavy-oil reservoir development, resulting in the significant enhancement of oil production. However, the underlying mechanism of multi-component coupling remains unclear. This paper constructs a coupling model for MTF stimulation, investigates the coupling mechanism of different media in various zones during multiple-cycle stimulation operations, and compares the implementation effect with field results. The findings reveal that (1) based on media distribution, the area from near-wellbore to far well locations can be divided into four zones: high-temperature oil-viscosity-reduction zones, compound action zones, energy-replenishment zones, and unaffected zones. (2) In the high-temperature oil-viscosity-reduction zone, the latent heat of vaporization is released by steam, and ultra-heavy oil absorbs heat and reduces its viscosity, which plays a dominant role in the production of MTF. In the compound action zone, hot water, CO2, and N2 exhibit a synergistic effect which enhances overall performance. In the energy-replenishment zone, a small amount of N2 provides pressure maintenance and an additional energy supply. (3) As more cycles of stimulation are conducted, the compound action zone expands, while the energy-replenishment zone contracts. Simultaneously, there is a decrease in contribution rate from the high-temperature viscosity-reduction zone to oil production but an increase from both the compound action zone and energy-replenishment zone up to 30%. Based on the dynamic law of representative wells, this paper proposes a multi-media zonal coupling mechanism, providing a reference for subsequent research on MTF stimulation mechanisms and the adjustment of production measures.

SpyTag Peptide with Alkoxyl Aspartic Acids for pH-Dependent Activation of the SpyCatcher/Tag System.

The SpyCatcher/SpyTag system is a protein pair that forms a covalent isopeptide bond without an additional energy supply. The ability to connect fused proteins makes this system an attractive tool for several protein engineering applications. Conditional activation of the SpyCatcher/SpyTag complex formation further expands the use of this system. Here, we evaluated the pH activation of SpyTag using alkoxyaspartic acids in the isopeptide-forming residue. We found that a peptide with an ethoxy group can be activated by hydrolysis under high pH conditions. However, the hydrolysis induces isoaspartate (isoAsp) formation, which is confirmed by an isoAsp-inserted short peptide. We overcame this problem by changing the C-terminal side of the aspartic acid position to Pro, which does not form isoAsp under high pH conditions. The findings of this study provide fundamental knowledge of the synthetic construction of the modified SpyTag peptide.

A polyurethane solid–solid phase change material for flexible use in thermal management

Phase change materials (PCMs) have received great attention in thermal management of electronic devices due to their high energy storage density and no need for additional energy supply. Yet the leakage problem after phase change limits their application greatly. In this paper, the block copolymerization was used to prepare a novel solid–solid phase change material (SSPCM) with a melting enthalpy of 90.26 J/g, starting pyrolysis at a temperature of more than 300 °C, and its physicochemical and thermal properties remained basically unchanged after 100 heating/cooling cycles. Notably, this SSPCM has excellent shape stability and can be pressed into phase change film with flexibility, thermally induced self-healing capability and recyclability. Finally, we innovatively combined this SSPCM, copper foam (CF), and polyimide tape (PI) to obtain a composite phase change material (CPCM) with both high thermal conductivity (1.1994 W/m·K) and high electrical insulating properties. Thermal management experiment shows that this CPCM has good thermal management performance and can significantly reduce the temperature rise rate of the simulated CPU. The SSPCM prepared in this study shows great potential for application in thermal management of portable electronic devices and flexible wearable electronic devices.

Revisiting the Dragonfly galaxy II. Young, radiatively efficient radio-loud AGN drives massive molecular outflow in a starburst merger at z = 1.92

ABSTRACT Radio-loud active galactic nuclei (RLAGNs) are a unique AGN population and were thought to be preferentially associated with supermassive black holes (SMBHs) at low accretion rates. They could impact the host galaxy evolution by expelling cold gas through the jet-mode feedback. In this work, we studied CO(6−5) line emission and continuum emission in a high-redshift radio galaxy, MRC 0152−209, at z = 1.92 using ALMA (Atacama Large Millimeter/submillimeter Array) up to a 0.024″ resolution (corresponding to ∼200 pc at z = 1.92). This system is a starburst major merger comprising two galaxies: the north-west (NW) galaxy hosting the RLAGN with jet kinetic power Ljet ≳ 2 × 1046 erg s−1 and the other galaxy to the south-east (SE). Based on the spectral energy distribution fitting for the entire system (NW+SE galaxies), we find an AGN bolometric luminosity LAGN, bol ∼ 3 × 1046 erg s−1 with a lower limit of ∼0.9 × 1046 erg s−1 for the RLAGN. We estimate the black hole mass through MBH–M⋆ scaling relations and find an Eddington ratio of λEdd ∼ 0.07–4 conservatively by adopting the lower limit of LAGN, bol and considering the dispersion of the scaling relation. These results suggest that the RLAGN is radiatively efficient and the powerful jets could be launched from a super-Eddington accretion disc. ALMA Cycle 6 observations further reveal a massive (${M}_\mathrm{H_2}=(1.1-2.3)\times 10^9\ \rm M_\odot$), compact (∼500 pc), and monopolar molecular outflow perpendicular to the jet axis. The corresponding mass outflow rate ($1200^{+300}_{-300}-2600^{+600}_{-600}\ \mathrm{M_\odot }\ \rm yr^{-1}$) is comparable with the star formation rate of at least $\sim 2100\ \mathrm{M_\odot }\ \rm yr^{-1}$. Depending on the outflowing molecular gas mass, the outflow kinetic power/LAGN, bol ratio of ∼0.008–0.02, and momentum boost factor of ∼3–24 agree with a radiative-mode AGN feedback scenario. On the other hand, the jets can also drive the molecular outflow within its lifetime of ∼2 × 105 yr without additional energy supply from AGN radiation. The jet-mode feedback is then capable of removing all cold gas from the host galaxy through the long-term, episodic launching of jets. Our study reveals a unique object where starburst activity, powerful jets, and rapid BH growth co-exist, which may represent a fundamental stage of AGN-host galaxy co-evolution.

Fabrication of thermal insulation sodium alginate/SiO2 composite aerogel with superior radiative cooling function for firefighting clothing

Purpose This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO2 and its radiative cooling effect on firefighting clothing without environmental pollution. Design/methodology/approach SA/SiO2 aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple. Findings When the addition of SiO2 is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO2 aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test. Research limitations/implications SA/SiO2 aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling. Practical implications This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters. Originality/value SA/SiO2 aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply. Graphical abstract

Stimuli Responsive Actuators：Recent Advances

Stimuli responsive soft actuators have gained significant interest in recent years due to their ability to move spontaneously and continuously without the need for additional energy supply. Moreover, those soft...

Numerical simulation of a two-phase flow in a jet mill ejector with an additional energy supply

New approaches to the preparation and processing of raw materials in the process of jet grinding are gaining more and more importance. This is due to the need to increase the efficiency of grinding and reduce the energy consumption of the equipment, increase its reliability and service life, and expand the possibility of using the jet mill in various industries. All this determines the importance of developing and implementing new approaches to two-phase flow organization in the channels of a jet mill. The goal of this work is to investigate a method for improving two-phase flow organization in the gas jet mill tracts. Numerical studies of a two-phase flow in the ejector of a jet mill showed the advisability of using an additional energy supply through the walls of the accelerating tube of the ejector to increase the efficiency of its operation. Controlling the gas flows in the mill ejector by using the energy of additional gas flows allows one to speed up the main flow at the exit of the ejector accelerating tube and form a protective layer around the tube walls to prevent their wear. The installation of a conical nozzle at the end of the accelerating tube prevents flow separation and vortex formation and provides a uniform velocity distribution at the ejector exit. The paper presents new solutions and recommendations on improving the efficiency of two-phase flow organization in the ducts of a gas jet mill. The scientific significance of the results lies in the development of a gas-dynamic method for controlling the gas flows in the jet mill tracts, which provides a uniform acceleration of the bulk material particles and reduces mill wear. The practical significance lies in the development of recommendations on increasing the efficiency of two-phase flow organization in the gas jet mill tracts. The results may be used in mining, metal manufacture, construction, the chemical and the food industry, and agriculture, and they will be employed in further development of scientific fundamentals of gas jet mill improvement.

Layout Optimization and Performance Analysis of Vehicle Suspension System Using an Electromagnetic Inerter

The inerter is a vibration isolation device used to replace the mass element in classical vibration isolation theory. The introduction of an inerter into a vehicle suspension system can greatly improve the performance of the system. An electromagnetic inerter is a kind of device that can realize a complex suspension structure without an additional energy supply and a complicated control system. It not only utilizes hydraulic systems to attain various suspension mechanical structures but also incorporates linear generators to form more intricate electrical networks. In this paper, an approach is proposed to achieve an optimized vehicle suspension layout using an electromagnetic inerter, which promotes the practical application of the device. First, seven suspension layouts are presented based on this device and relevant models are established to optimize the performance of these seven layouts under certain objectives. Then, the influence of three factors of the electrical network, namely linear generator internal resistance, inductance, and linear generator coefficient, on suspension performance is analyzed. At the same time, to ensure the suspension performance of this device is closer to that required for actual engineering applications, the improvement in the vibration isolation performance of the device compared with traditional passive suspension is discussed considering these three factors. The final results show that when considering the real-world situation, the L1 and L4 layouts can achieve excellent performance improvement, with RMS(BA) values of only 85.73% and 84.66% of the traditional passive suspension.

Hydrodynamic tearing of bacteria on nanotips for sustainable water disinfection

Water disinfection is conventionally achieved by oxidation or irradiation, which is often associated with a high carbon footprint and the formation of toxic byproducts. Here, we describe a nano-structured material that is highly effective at killing bacteria in water through a hydrodynamic mechanism. The material consists of carbon-coated, sharp Cu(OH)2 nanowires grown on a copper foam substrate. We show that mild water flow (e.g. driven from a storage tank) can efficiently tear up bacteria through a high dispersion force between the nanotip surface and the cell envelope. Bacterial cell rupture is due to tearing of the cell envelope rather than collisions. This mechanism produces rapid inactivation of bacteria in water, and achieved complete disinfection in a 30-day field test. Our approach exploits fluidic energy and does not require additional energy supply, thus offering an efficient and low-cost system that could potentially be incorporated in water treatment processes in wastewater facilities and rural communities.

Optimal Contracting of Transmission System Usage Combined With Subtransmission Planning via Cross-Entropy Method

Local power distribution companies (DISCOs) are not self-sufficient in electricity to serve their customers and require importing additional energy supply from the interconnected bulk power systems. In Brazil, they annually carry out the contracting process for the amount of transmission system usage (ATSU) for the next four years. This process is a real example of a task that involves decisions under uncertainty with a high impact on the productivity of DISCOs and the electricity sector in general. The task becomes even more complex in face of the increasing variability associated with the generation of renewable energy and the changing profile of the consumer. In this work, the main objective is to develop a methodology based on probabilistic power flow and cross-entropy techniques to assess the optimal contracting under uncertainty of the ATSU, combined with the expansion plan for the subtransmission network. As the robustness of the network influences the power import by the DISCO, there are real measurable benefits to assessing contracts and grid expansion altogether. Results with academic and real systems show that the proposals reduce the total costs with ATSU contracts.

Edge-Based Short-Term Energy Demand Prediction

The electrical grid is gradually transitioning towards being an interconnected area of the smart grid, where embedded devices operate in an autonomous manner without any human intervention. An important element for this transition is the energy demand prediction, since the needs for energy have substantially increased due to the introduction of new and heavy consumption sources, such as electric vehicles. Accurate energy demand prediction, especially for short-term durations (i.e., minutes to hours), allows grid operators to produce the substantial amount needed to satisfy the demand–response equilibrium and avoid peak electricity load conditions that may also lead to blackouts in densely populated areas. However, to achieve such an accuracy level, machine learning (ML) models require extensive training with historical measurements, which is usually resource intensive (e.g., in memory and processing power). Hence, deriving accurate predictions for short-term energy demands is challenging due to the absence of external factors such as environmental data from different regions and seasons and categorical values such as bank/bridging holidays in the ML model. Additionally, existing work focuses on ML model execution on Cloud platforms, which usually does not satisfy the real-time requirements of grid operators for short-term energy demand predictions. To address these challenges, this article presents a new method that considers environmental factors and categorical values to build an energy profile for each consumer in a multi-access edge computing (MEC) framework. The method is also based on the Temporal Fusion Transformer (TFT) ML model, which allows it to learn the temporal dependencies of the gathered historical measurements and predict energy demands with satisfying accuracy. The method is applied to a home energy management system testbed containing photovoltaic systems, smart meters, sensors and actuators for detecting environmental factors (i.e., temperature, humidity and radiation) as well as energy storage systems as an additional energy supply source. The MEC framework is deployed in data concentrator devices where the TFT ML model is executed with low resource requirements, ensuring additional security as the data do not leave the location where they are produced.

Electronic communication between transition metal nanoparticle and single atom: Endohedral metallofullerenes single-atom catalysts for oxygen reduction reaction catalysis

Civil-used proton exchange membrane fuel cell (PEMFC) may be the potential candidate for the construction of the global new energy system including the use of hydrogen energy. Nevertheless, the cathode oxygen reduction reaction (ORR) occurs sluggishly, reining the conversion efficiency of it, which hinders the further commercialization of PEMFC. Currently, the replacement of undesirable Pt catalysts by more stable and economical catalytic materials is the main topic in the field of ORR. Herein, ferromagnetic metal-based endohedral metallofullerenes (EMFs) electrocatalyst with single-atomic shell decoration (M4@MN4C60, M = Fe, Co, Ni) are theoretically constructed and evaluated by the density functional theory method. The encapsulation energy calculation reveals that the synthesis of all EMFs requires additional external energy supply, which can explain why few successfully experimental synesis of EMFs have been reported. Among all studied catalysts, the CoN4C60 stands out with the highest ORR performance comparable to Pt, and the Fe- and Ni- based EMFs shows considerable activity enhancement after the cluster encapsulation. The electronic structure calculation reveals that the encapsulated Fe4 cluster leads to an electron accumulation around the Fe atom in active center, thereby weakening the *OH binding and enhance the ORR performance.

President's Page: Energy transition offers bright future for geoscientists

As the world's population continues to grow and economies develop, there will be a commensurate need for additional energy supply that is sustainable and that can be acquired while respecting the environment. The Middle East, home to some of the world's largest oil and gas reserves, is one of the most important regions globally for energy production and exports. Countries such as Saudi Arabia and the United Arab Emirates are key players in the global oil market, while Qatar is a major exporter of liquified natural gas. Fossil fuels will continue to play a major role in the region's — and the world's — energy mix for the foreseeable future, but there is growing interest in developing renewable energy sources such as solar, wind power, and geothermal.

Room temperature mixed-potential solid-electrolyte NO2 sensor for environmental monitoring

Mixed-potential solid-electrolyte (MPSE) gas sensors have important applications for the detection of hazardous NO2. However, limited by the poor conductivity of conventional electrolytes at low temperatures, the realization of high performance of MPSE gas sensors usually requires a compromise to high working temperatures, hindering their application. To this end, we developed a novel ultrasensitive and selective MPSE NO2 sensor based on K2Fe4O7 solid electrolyte and Ni-MOF|N2 sensing electrode (SE), which can achieve a low detection limit (LOD) as low as 5 ppb at room temperature (RT) without additional energy supply. Simultaneously, the selectivity of the sensor to the interfering gas NO achieves a 31-fold improvement by the enhanced participation of H2O molecules and unsaturated coordinated Ni ions, which are obtained by the sintering in anoxic atmospheres like N2 or Ar. Moreover, the sensor is further used as the information collection terminal of the Internet of Things (IoT) system, building a NO2 monitoring network for remote monitoring, different environment evaluation, and information sharing. This work fills the gap of the ultrasensitive MPSE NO2 sensor in the RT field and provides new insights for the construction of NO2 portable sensor networks.

Self-Powered DNAzyme Walker Enables Dual-Mode Biosensor Construction for Electrochemiluminescence and Electrochemical Detection of MicroRNA.

Herein, an electrochemiluminescence (ECL) and electrochemical (EC) dual-mode biosensor platform with a self-powered DNAzyme walking machine was established for accurate and sensitive detection of miRNA-21. By employing a magnesium ion (Mn2+)-dependent DNAzyme cleavage cycling reaction, the walking machine was built by assembling DNAzyme walking strands and ferrocene (Fc)-labeled substrate strands on the Au nanoparticles and graphitic carbon nitride nanosheet (g-C3N4 NS)-covered electrode. The DNAzyme walking strand was first prohibited by a blocker strand. After the addition of target miRNA-21 and Mn2+, the DNAzyme walker could be activated and produce autonomous movements along the electrode track fueled by Mn2+-dependent DNAzyme-catalyzed substrate cleavage without additional energy supply. Notably, each walking step resulted in the cleavage of a substrate strand and the release of a Fc-labeled DNA strand fragment, allowing us to acquire an extreme ECL signal recovery of g-C3N4 inhibited by Fc. Meanwhile, numerous Fc-labeled DNA fragments escaped from the surface of the electrode, directly producing an obvious decrease in the square wave voltammetry (SWV) signal from Fc on the same sensing platform. This work not only avoided difficultly assembling various signal indicators but also significantly improved the sensitivity through using self-powered DNAzyme-walker amplification. Moreover, the proposed design employed the same reaction to produce two signal output modes, which could eliminate the interference from diverse reactive pathways on the outcome to mutually improve the accuracy. Therefore, the dual-mode miRNA-21 biosensor exhibited wide detection ranges of 100 aM to 100 nM with low detection limits of 54.3 and 78.6 aM by ECL and SWV modes, respectively, which provided an efficient and universal biosensing approach with extensive applications in early disease diagnosis and bioanalysis.

Self-powered molecular imprinted photoelectrochemical sensing platform of sialic acid employing WO3/Bi2S3 photoanode and CuInS2 photocathode

A dual-photoelectrode molecular imprinted photoelectrochemical (PEC) sensor is first built for the determination of sialic acid (SA) without additional energy supply. Specifically, WO3/Bi2S3 heterojunction behaves as a photoanode to provide amplified and stable photocurrent for the PEC sensing platform, which is attributed to the matched energy levels of WO3 and Bi2S3 promoting the electron transfer and improving photoelectric conversion properties. CuInS2 micro-flowers functionalized by molecularly imprinted polymers (MIPs) are served as photocathode to recognize SA, avoiding the deficiency of high production cost and poor stability from biological enzymes, aptamers, or antigen-antibodies. The inherent deviation between the Fermi level of the photoanode and the photocathode guarantees a spontaneous power supply for the PEC system. Benefiting from the photoanode and recognition elements, the as-fabricated PEC sensing platform has a strong anti-interference ability and high selectivity. Moreover, the PEC sensor displays a wide linear range of 1 nM–100 μM and a low detection limit of 7.1 × 10−10 M (S/N = 3) based on the relationship between photocurrent signal and SA concentration. Accordingly, this research provides a new and valuable approach to detecting various molecules.

Experimental performance evaluation of multiple-effect diffusion stills under high heat flux

Active stills equipped with additional energy supply devices for enhancing productivity can select the amount of heat flux supply. However, most previous studies have been conducted at a heat flux below 1.0 kW/m2, which can be obtained naturally, and only a few investigated heat flux optimization. In this study, the optimal heat flux and feed flow rate of an active multiple-effect diffusion still (MEDS) were evaluated experimentally at a high heat flux above 1.0 kW/m2 to maximize its performance. An MEDS with 15 effects was fabricated, and its performance was investigated according to the feed flow rate under a heat flux range of 1.0–2.5 kW/m2. The results showed that the freshwater production efficiency in terms of performance ratio (PR) increased with heat flux up to 2.18. The MEDS achieved 8.7 kg/(m2·h) at 2.5 kW/m2. The optimal feed flow rate was identified based on the heat flux at which the MEDS exhibited the maximum output. The cost analysis showed that the MEDS using waste heat has a very attractive water cost of 1.0–3.0 $/m3 at high heat fluxes, which is competitive with even other conventional desalination technologies. Therefore, the active MEDS at higher heat flux shows better performance and lower water cost.