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For the long-term dynamic simulation of a fluidized bed reactor (FBR), a two-way coupled computational fluid dynamics (CFD)-direct quadrature method of moments (DQMOM) approach is proposed. In this approach, CFD is first used only for hydrodynamic information without simulating any other chemical reactions or physical phenomena. Subsequently, the derived information is applied to the DQMOM calculation in MATLAB. From the calculation, a particle size distribution is obtained and subsequently adopted in a new CFD model to reflect the flow change caused by a change in the particle size distribution. Through several iterative calculations, long-term dynamic simulations are performed. To evaluate the efficacy of the proposed approach, the results from the suggested approach are compared for 60 s with those of the CFD-quadrature method of moments (QMOM) approach, which calculates hydrodynamics and physical phenomena simultaneously in CFD. The proposed approach successfully simulated the FBR for 6 h. The results confirmed that the proposed method can simulate complex flow patterns, which cannot be obtained in conventional CFD models. Another advantage of the approach is that it can be applied to various industrial multiphase reactors without any tuning parameters.

MXenes have received much attention as promising candidates for noble metal-free hydrogen evolution reaction (HER) electrocatalysts due to their high electrical conductivity, surface hydrophilicity, abundant surface functional groups, and great potential for rational hybridization with other materials. Herein, a novel porous monolayered-Ti3C2Tx@NiCoP (P-Ti3C2Tx@NiCoP) nanostructure was synthesized with uniform distribution of bimetallic compounds for improved charge transfer capability and electrocatalytic activity. In experiments, H2O2-utilized oxidation formed a highly mesoporous structure with a maximized surface area of monolayered MXenes as the support. A subsequent solvothermal process followed by phosphidation enabled successful anchoring of highly HER-active NiCoP nanoclusters onto abundantly exposed terminal edges of the P-Ti3C2Tx support. The structural porosity of the P-Ti3C2Tx nanoflakes played an important role in creating additional room for embedding catalytically active species while stably imparting high electrical conductivity to accelerate charge transfer to NiCoP nanoclusters. With structural modification and effective hybridization, P-Ti3C2Tx@NiCoP showed highly enhanced HER activity with significantly lower overpotentials of 115 and 101 mV at a current density of -10 mA cm-2 in 0.5 M H2SO4 and 1.0 M KOH, respectively, along with showing long-term stability over 60 h. As such, our approach of designing structurally modified-Ti3C2Tx and hybridizing with other electrocatalytically active species would function as a solid platform for implementing Ti3C2Tx-based hetero-nanostructures to achieve state-of-the-art performance in next-generation energy conversion applications.

Mesoporous TiO2 films are synthesized through evaporation-induced self-assembly using poly(ethylene oxide-b-ε-caprolactone) diblock copolymers as a soft-template. Using small-angle X-ray scattering and scanning electron microscopy, we investigate the effect of the TiO2/PEO-b-PCL ratio on the resulting nanoarchitectonic structure. After sputter-coating Au and Pt layers, these Au/TiO2 and Pt/TiO2 nanocomposite films display drastically enhanced photodegradation of rhodamine 6G under ultraviolet irradiation, due to the metal films inhibiting the rapid recombination of photogenerated charge carriers.

Carbonyl compounds have potential for use as cathode materials of secondary batteries because of their large specific capacities, stable redox active centers, high efficiencies and ability to regenerate, however their intrinsic solubilities and low electrical conductivities present challenges to hinder their practical utilization. Here, three-dimensional nanoporous polyquinoneimines (PQ) were synthesized by hydrothermal polymerization reactions, and examined as electrode materials in lithium-ion batteries to solve these problems of solubility and electronic conductivity. The large specific surface area (116.95 m2 g−1) and abundant pore structure (0.2428 cm3 g−1) of the PQ, which were formed by the anisotropic growth of nanosized rose flakes, shortened the lithium-ion diffusion path and reduced lithium solubility. The capacities of the PQ electrodes of 1 mg cm−2 were 228 (1st cycle; theoretical capacity of PQ with 4 electron reaction is 228 mAh g−1) and 103 (1000th) mAh g−1 at 50 mA g−1, and the declined rate per cycle at 200 mA g−1 was only 0.05% (0.077 mAh g−1 per cycle) within the first 1000 cycles. The capacity of the 500th cycle with a high load of 3 mg cm−2 was 123 mAh g−1, exhibiting a coulombic efficiency of 99%. The molecular structure during lithiation was calculated with density functional theory and showed that the robust bridge bond formed and promoted the electrochemical activity of the charge/discharge process.

Summary In recent years, metal-organic framework (MOF)-derived carbon materials (CMs), known for their nanoporous structure yielding a high surface area and tunable chemical and physical properties, have drawn great interest in many fields of application, such as energy storage and conversion, environmental remediation, and catalysis. Despite the tremendous efforts involved in their development, several common drawbacks still persist during the carbonization process: (1) the intrinsic nature of micropore-dominated porous structure (limited diffusion), (2) the irreversible aggregation of metal nanoparticles, and (3) the poor control over structural evolution, which largely thwart their performance. To overcome these technical limitations, many new strategies are currently emerging to boost the development of MOF-derived nanoarchitectured CMs (NCMs). These new approaches can be considered new chemistry tools utilizing SiO2, polymers, surfactants, and others. In this review, we focus on the synthetic mechanisms of these new methods by summarizing recent findings related to MOF-derived NCMs.

A new chemical method is developed for the preparation of a unique one-dimensional (1D) Sn(IV) hydroxide nanofluid. The 1D-Sn(IV) hydroxide nanowires of ca. 600 nm in length and ca. 25 nm in width yield transparent glass type flakes when the nanofluid is dried in air. The stability of the system, keeping it safe from sedimentation even after a year, is believed to rely on its high zeta-potential of ca. 55 mV (± 2.5 mV). We extensively investigate the thermal conductivity and viscosity of the system in order to evaluate its nanofluidic merits, resulting in thermal conductivity exceeding 1 W m−1 K−1. The nanofluid is further investigated for nonlinear optics (NLO) applications, revealing a reversible switching from positive Z-scan (convex lens) to negative Z-scan (concave lens) of the nonlinear phase when the laser power is tuned from 500 to 1000 μW.

Highly efficient nanoparticle-on-metallic-mirror (NPOM) systems with a large gap size exhibiting good plasmonic enhancement are desirable for numerous practical applications. Careful, explicit design optimization strategies are required for preparing NPOMs and it is especially important in utilizing spherical nanoparticles. In this work, a new design blueprint for evaluating the role of random facets in spherical nanoparticles was investigated in detail to realize optimal NPOMs. We found that a precise single facet positioned at the nanoparticle's cavity outperformed multiple random facets due to the gap mode contribution. Differences and changes in the plasmonic modes were interpreted with the help of three-dimensional surface charge density mappings. A high-performance, single, bottom-faceted NPOM device with a large gap size (example 20 nm) was realized having 80-50% facet design, resulting in excellent gap mode enhancement. We succeeded in fabricating single bottom-faceted NPOMs (the non-facet region had a smooth spherical surface) with a large-scale unidirectionality (2 cm × 1.5 cm). Simulations and experimental characterizations of these components displayed excellent agreement. Our highly efficient NPOM design with a large gap size(s) enables interesting practical applications in the field of quantum emitters, energy devices, fuel generation and plasmon chemistry.

In this study, three-dimensional (3D) ZIF-8-derived carbon (ZIF-8C) polyhedrons have been successfully coated with polydopamine (PDA) nanothin layer via a facile synthetic method that exploits oxidative self-polymerization of dopamine in alkaline solutions. It is observed that ca. 20 nm of PDA nanothin film is coated on ZIF-8C surface with a good homogeneity. Our results show clear morphological changes in core-shell structured PDA-coated ZIF-8C (ZIF-8C@PDA) as compared to bare ZIF-8C. In addition, the cyclic voltammetry shows conspicuous redox peaks in ZIF-8C@PDA. The observed redox activity is attributed to a series of redox reactions of oxygen species of catechol and quinone groups of PDA. With superior adhesive property and redox activity as additional surface functionality, ZIF-8C@PDA can be used in various applications, especially in energy storage applications in the future.

Naphthalene diimide (NDI)-based copolymers are promising polymer acceptors in all-polymer solar cells (all-PSCs), but their large crystal domains cause large-scale phase separation in all-polymer blend films. This limits the photovoltaic performance and mechanical stability of all-PSCs. Herein, we control all-polymer blend films by introducing a fluorinated copolymer of NDI and (E)-1,2-bis(3-fluorothiophen-2-yl)ethene (FTVT) (PNDI–FTVT) as a polymer acceptor for flexible all-PSCs. The copolymer PNDI–FTVT has a less crystalline structure and higher electron mobility than its nonfluorinated copolymer counterpart (PNDI–TVT). A blended film incorporating PNDI–FTVT exhibits a well-mixed morphology and improves the chain interconnectivity with a polymer donor, providing better charge transport pathways and enhanced mechanical resilience. The PNDI–FTVT-based flexible all-PSC exhibits enhanced photovoltaic performance in comparison with a PNDI–TVT-based flexible all-PSC (5.11–7.14%) as well as excellent mechanica...

Naphthalene diimide (NDI)-based conjugated polymers with bithiophene or dithienylethene (TVT) units can form large crystal domains through NDI-driven self-assembly and are widely used in organic electronic devices as n-type materials. However, improving electron transport in these semiconducting polymers has been a significant challenge mainly due to poor electrical connections between the crystal domains. Formation of an interconnected network of small domains with short-range ordering and mixed orientations could be an effective way of increasing the electron mobility (μe) of polymeric materials. The present study demonstrates the feasibility of this approach using an NDI-based polymer composed of fluorinated TVT (FTVT) units. The FTVT unit enhances intermolecular interactions between the polymer chains, leading to robust aggregation. This aggregation was found to suppress NDI-driven self-assembly, resulting in interconnected small crystal domains with short-range ordering and good thermal stability at ...

We develop a rigorous mathematical model of aqueous mineral carbonation kinetics for carbon capture and utilization (CCU) and estimate the parameter posterior distribution using Bayesian parameter ...

Carbon materials, especially N-doped carbon materials with a one-dimensional (1D) hollow structure, have attracted great attention as one of the most efficient and eco-friendly catalysts for advanced oxidation processes (AOPs). The complex synthesis process of 1D hollow carbon however remains a major challenge in meeting the growing demand for it as a superior carbon-based catalyst. Herein, we demonstrate a facile strategy to synthesize 1D hollow carbon nanofibers (HCNFs) in a scalable manner. In this study, zeolitic imidazolate framework-8 (ZIF-8)/polyacrylonitrile (PAN) fibers were fabricated via electrospinning, and subsequent pyrolysis of the as-prepared ZIF-8/PAN composite nanofibers produced HCNFs. With excellent structural advantages and N-doped composition, HCNFs exhibited a remarkable level of catalytic degradation of tetracycline (TC) in the peroxymonosulfate (PMS) activation system. Furthermore, the HCNFs also showed good mechanical flexibility. A catalytic device was then constructed to explore the potential applications of HCNFs.

The possibility of future potential applications, spanning from military dark-vision displays and data undergird devices to civilian medical nosology and photobiomodulation light therapy, has created an enormous demand for the development of highly efficient, stable, flexible, and low-cost deep-red emitting luminophores. Herein, two new deep-red (650–800 nm) emissive iridium(III) complexes, Ir1-pic and Ir2-pic, have been developed, based on electron-donating –CH3 substituted and unsubstituted cyclometalating (benzo[b]thiophen-2-yl)quinoline and picolinate ancillary ligands, the structures and distorted octahedral coordination motifs of which were authenticated by single-crystal X-ray diffraction analysis. An in-depth study on the effect of the ancillary ligands on the excited-state process was carried out and the results were compared with reference compounds containing thenoyltrifluoroacetylacetonate in place of the picolinate ancillary ligand. The rigid nature and high triplet energy levels of the picolinate ancillary ligand led to a robust deep-red emission; however, the triplet spin density population and flexible nature of the β-diketonate ancillary ligand triggered an excited-state geometrical deformation, leading to the opening up of dominant, unfavorable, nonradiative pathways. Most importantly, the picolinate coordinated complexes Ir1-pic and Ir2-pic were found to exhibit excellent emission efficiencies (ΦPL = 0.48 and 0.37, respectively) and were effectively employed as deep-red dopants in organic light-emitting diodes, constructed via a solution-processed approach. The unoptimized Ir1-pic and Ir2-pic-based devices with various doping ratios were found to have maximum external quantum efficiency values of 5.03% and 3.41%, respectively.

Herein, poly(3-hexylthiophene) films with periodic wavy surface structures are generated upon laser irradiation at a wavelength of 530 nm using a pulse duration of 5 ns and a repetition frequency of 10 Hz. The optical properties of the films irradiated with 1200, 3000, and 6000 pulses, respectively, are studied using various techniques.

In recent years, naturally occurring compounds found in plants (also known as phytochemicals) have found increasing application in the synthesis of metal oxide nanostructures due to their multi-role as reducing agents, capping agents, and/or complexing agents. Furthermore, the utilization of natural agents, such as phytochemicals provide a green and sustainable way for fabricating metal oxide nanostructures compared to conventional chemical methods. This perspective will cover various types of plant-derived phytochemicals which have been employed in the preparation of metal oxide nanostructures, including their roles and the associated formation mechanisms. This review will also discuss some prospective applications of phytochemical-derived metal oxide nanostructures for energy storage, environmental remediation, and bio-related applications. Finally, some perspectives on the future direction of the synthesis of metal oxide nanostructures via green chemistry will be provided.

This study presents a computational fluid dynamics (CFD) based optimal design tool for chemical reactors, in which multi-objective Bayesian optimization (MBO) is utilized to reduce the number of required CFD runs. Detailed methods used to automate the process by connecting CFD with MBO are also proposed. The developed optimizer was applied to minimize the power consumption and maximize the gas holdup in a gas-sparged stirred tank reactor, which has six design variables: the aspect ratio of the tank, the diameter and clearance of each of the two impellers, and the gas sparger. The saturated Pareto front is obtained after 100 iterations. The resulting Pareto front consists of many near-optimal designs with significantly enhanced performances compared to conventional reactors reported in the literature. We anticipate that this design approach can be applied to any process unit design problems that require a large number of CFD simulation runs.

Mesostructured polydopamine (PDA) coating has been successfully achieved on the surface of zeolitic imidazolate framework-8 (ZIF-8) particles by incorporating Pluronic F127 (with a pore-expanding agent, 1,3,5-trimethylbenzene) as a pore-directing agent during dopamine polymerization. Upon pyrolysis at high temperatures, mesostructured PDA-coated ZIF-8 particles become hierarchically porous double-shell carbons (HPDCs) with a wide pore size distribution ranging from micro- and meso- to macropores. The formation of a hollow inner shell progresses initially with the shrinkage of ZIF-8 at the periphery where the interface interactions with mesostructured PDA exist, and then the subsequent disintegration of the ZIF-8 core at higher temperatures occurs. Our HPDCs prepared in this study feature physical and electrochemical advantages of hierarchically porous carbons such as high electrochemically accessible surface area, short diffusion distance, and high mass-transfer rate, thus demonstrating significantly improved ion diffusion and surface-enhanced high specific capacitance at high charge-discharge rates. HPDC5.0 therefore exhibits the capacitance retention of up to 76.7% from 1 to 10 A g-1 and maximum specific capacitance of 344.7 F g-1 at 1 mV s-1. It also possesses superior electrochemical stability with about 108% capacitance retention even after 10,000 consecutive cycles of galvanostatic charge-discharge at 10 A g-1.

In anticipation of the successful establishment of carbon capture, utilization, and storage (CCUS) technology, a pilot-scale aqueous mineral carbonation plant, that removes CO2 through a reaction with a Ca(OH)2 solution, was built in Incheon, South Korea. Using computational fluid dynamics (CFD), two reactors with a diameter of 2.2 m and a height of 6.0 m were modeled and validated for reactor scale-up and optimization. Because a direct simulation of bubble breakage, coalescence, and interphase mass transfer results in enormous computational costs for modeling the pilot-scale multiphase reactor, a CFD-lumped correlation model was introduced to simulate a large reactor; this resulted in acceptable computational costs and maintained the simulation accuracy. In order to ensure the acceptability of the CFD model, two-step verification was conducted. The CFD model results were compared with the experimental data and published empirical correlations with regard to the gas holdup, interfacial area, and mass transfer coefficient. Subsequently, the CO2 removal efficiencies of the CFD model were compared with the pilot-plant data. The errors of the CFD model for three hydrodynamic parameters and the CO2 removal efficiencies were in the range of 1–8%. The validated CFD model will be used for designing a four times larger mineral carbonation reactor, that will be built in 2017.

Research on near-infrared- (NIR-) emitting materials and devices has been propelled by fundamental and practical application demands surrounding information-secured devices and night-vision displays to phototherapy and civilian medical diagnostics. However, the development of stable, highly efficient, low-cost NIR-emitting luminophores is still a formidable challenge owing to the vulnerability of the small emissive bandgap toward several nonradiative decay pathways, including the overlapping of ground- and excited-state vibrational energies and high-frequency oscillators. Suitable structural designs are mandatory for producing an intense NIR emission. Herein, we developed a series of deep-red to NIR emissive iridium(III) complexes (Ir1–Ir4) to explore the effects of electron-donating and electron-withdrawing substituents anchored on the quinoline moiety of (benzo[b]thiophen-2-yl)quinoline cyclometalating ligands. These substituents help engineer the emission bandgap systematically from the deep-red to the NIR region while altering the emission efficiencies drastically. Single-crystal X-ray structures authenticated the exact coordination geometry and intermolecular interactions in these new compounds. We also performed an in-depth and comparative photophysical study in the solution, neat powder, doped polymer film, and freeze matrix at 77 K states to investigate the effects of substitution on the excited-state properties. These studies were conducted in conjunction with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. Most importantly, the –CH3 substituted Ir1, unsubstituted Ir2, and –CF3 substituted complex (Ir4) were promising novel compounds with bright phosphorescence quantum efficiency in doped polymer films. Using these novel molecules, deep-red to NIR emissive organic light-emitting diodes (OLEDs) were fabricated using a solution-processable method. The unoptimized device exhibited maximum external quantum efficiency (EQE) values of 2.05% and 2.11% for Ir1 and Ir2, respectively.

Rational design of electrocatalysts with the tuneable structural and electrocatalytic properties are essential to accomplish bifunctional activity of hydrogen and oxygen evolution reaction (HER/OER), and thus efficient water splitting systems. Here, we present a bifunctional hybrid electrocatalyst consisting of Co9S8 (OER-active) and MoS2 (HER-active) with the structural merits of hierarchical morphology, huge electrochemically active sites, and greater charge transfer ability. The structural features of the hybrid electrocatalyst (Co9S8@MoS2/N-doped hollow carbon) that is derived from metal organic framework (MOF) precursor are elaborately controlled by the temperature dependent-Kirkendall diffusion effect. Specifically, the imbalanced diffusion rates between two ionic species (Co2+ and S2−), confined in the MOF-precursor geometry, induces the formation of internal voids and outward growth of Co9S8 while retaining MoS2 layers on the surface. As a result, the hybrid electrocatalyst exhibits greatly enhanced HER (126 mV@−10 mA cm−2) and OER (233 mV@10 mA cm−2) performance. Furthermore, the bifunctional electrode couple demonstrates efficient overall water splitting performance (1.56 V@10 mA cm−2) compared to the benchmark electrode couple of IrO2/C//Pt/C (1.63 V@10 mA cm−2) in 1 M KOH solution. The results highlight that inducing “Kirkendall effect” through temperature-tuning approach for structure-properties modulation can be extensively applied to design various bifunctional hybrid electrocatalysts.

We report a pentafluorobenzene-based additive (FPE) to control the donor/acceptor (D/A) interfacial morphology via quadrupolar electrostatic interactions between donor and acceptor polymers in all-polymer solar cells (all-PSCs). The morphology changes are investigated using a combination of atomic force microscopy, grazing incidence wide-angle X-ray scattering, and near-edge X-ray absorption fine-structure spectroscopy. Unlike a conventional solvent additive, such as 1,8-diiodooctane, a bicontinuous interpenetrating morphology without large-scale phase separation and an enhanced π–π stacking with face-on orientation are found in the FPE processed blended films. These morphology changes improve the charge carrier extraction and charge transport between D/A interfaces to achieve an increase in the photovoltaic performance of all-PSCs.

Mesoporous noble metals and their patterning techniques for obtaining unique patterned structures are highly attractive for electrocatalysis, photocatalysis, and optoelectronics device applications owing to their expedient properties such as high level of exposed active locations, cascade electrocatalytic sites, and large surface area. However, patterning techniques for mesoporous substrates are still limited to metal oxide and silica films, although there is growing demand for developing techniques related to patterning mesoporous metals. In this study, the first demonstration of mesoporous metal films on patterned gold (Au) substrates, prefabricated using photolithographic techniques, is reported. First, different growth rates of mesoporous Au metal films on patterned Au substrates are demonstrated by varying deposition times and voltages. In addition, mesoporous Au films are also fabricated on various patterns of Au substrates including stripe and mesh lines. An alternative fabrication method using a photoresist insulating mask also yields growth of mesoporous Au within the patterning. Moreover, patterned mesoporous films of palladium (Pd) and palladium-copper alloy (PdCu) are demonstrated on the same types of substrates to show versatility of this method. Patterned mesoporous Au films (PMGFs) show higher electrochemically active surface area (ECSA) and higher sensitivity toward glucose oxidation than nonpatterned mesoporous Au films (NMGF).

Biomass-derived carbons are widely studied as cost-effective and high-performance energy storage materials due to their high specific surface area, abundance, and facile synthetic methods. Through widespread research, a number of strategies can be implemented to maximize specific capacitance and power. Among the different approaches to improve the energy storage performance of biomass-derived carbons, an increase of specific surface area and the introduction of heteroatom doping are usually effective strategies. As such, in this study, we utilize sorghum stem biomass to obtain porous carbonaceous forms, and subsequent KOH activation to increase the porosity and surface area. The resulting activated sorghum stem-derived porous carbon materials exhibit significantly higher specific capacitance compared to their pre-activated carbon. Capacitive deionization (CDI) that is used to deionize water is also studied to demonstrate the versatility of sorghum stem-derived porous carbon. A similar performance trend is observed for both supercapacitor and CDI for all carbon samples because both applications exploit the electrostatic double-layer capacitance behavior of carbon materials.

산화 칼슘 수용액을 통해 이산화탄소를 포집하는 수성 광물 탄산화 공정은 안정적으로 이산화탄소를 고립시킬 뿐아니라 생성물의 부가 가치를 기대할 수 있는 대표적인 CCU (Carbon Capture & Utilization) 기술이다. 이 공정의 핵심은 고체 반응물인 산화칼슘의 용해 속도를 최대로 높이는 것인데, 이를 위해 반응기 전체에 고체 반응물이 균일하게 분포되도록 혼합하는 적절한 반응기의 설계가 필요하다. 본 논문에서는 하루에 40ton의 이산화탄소 포집이 가능한 파일럿 규모의 광물 탄산화 반응기를 대상으로, 반응기의 내부 구조 설계에 따라 고체 반응물의 분산도가 어떻게 변하는 지에 대해 전산 유체 역학적 모델링(Computational Fluid Dynamics (CFD) modeling)을 통해 연구하였다. 교반 탱크 반응기(stirred tank reactor) 형태를 기반으로 외부 구조는 고정한 상태에서 교반기의 종류/갯수/지름/유격/회전 속도, 칸막이의 높이/너비를 변수로 선정하여 다양한 조합의 경우(case)들을 해석하였다. 각 설계 변수에 대한 민감도를 분석함 으로써 각 변수의 영향을 파악하고, 중요한 변수를 판별할 수 있었다. 동시에 고체 부피 분율(solid volume fraction)의 높이 방향 표준 편차가 0.001에 가까운 균일한 분포를 만들 수 있는 내부 설계안을 제안하였다.

Pilot- and industrial-scale mineral carbonation plants to remove CO2 through a reaction with Ca(OH)2 were built in South Korea to address concerns related to global warming. To simulate mineral carbonation reactors with complex gas–liquid–solid interacting flow patterns, a computational fluid dynamics (CFD)-based compartmental model was developed. In the model, the reactors were divided into hundreds of zones, and each zone was assumed to be a single homogeneous reactor. Mass and heat balance equations were formulated for each zone and the entire reactor, separately. The mass flow rates between adjacent zones and initial CO2 holdup at each zone were calculated from CFD simulations, and a kinetic model, which included all the involved reactions, was built in MATLAB. The total CO2 removal efficiency, pH, and temperature changes as well as concentration profiles of CO2 and other species were predicted during batch operations. To validate the performance of the model, the simulated results were compared with the real operation data from the pilot- and industrial-scale plants. The errors at steady states were within 7% without any adjustable parameters. Furthermore, the model was used to predict the performances of reactors 2.5 and 10 times larger than the industrial-scale reactor.

Electron-doped SrTiO 3 is a well-known n -type thermoelectric material, although the figure of merit of SrTiO 3 is still inferior compared with p -type metal oxide-based thermoelectric materials due to its high lattice thermal conductivity. In this study, we have used a different amount of the non-ionic surfactant F127 during sample preparation to introduce nanoscale porosities into bulk samples of La-doped SrTiO 3 . It has been observed that the porosities introduced into the bulk sample significantly improve the Seebeck coefficient and reduce the thermal conductivity by the charge carrier and phonon scattering respectively. Therefore, there is an overall enhancement in the power factor (PF) followed by a dimensionless figure of merit ( zT ) over a wide scale of temperature. The sample 20 at% La-doped SrTiO 3 with 600 mg of F127 surfactant (SLTO 600F127) shows the maximum PF of 1.14 mW m −1 K −2 at 647 K which is 35% higher than the sample without porosity (SLTO 0F127), and the same sample (SLTO 600F127) shows the maximum value of z T is 0.32 at 968 K with an average enhancement of 62% in zT in comparison with the sample without porosity (SLTO 0F127).

Mass interfacial processes have been considered as one of the crucial factors supporting fundamental research. Due to the low cost and conceptual simplicity, significant advancements have been achieved in the development of methodologies based on piezoelectric devices for in situ determination of mass changes on the surfaces of deposited materials under various conditions. The introduction of nanomaterials for designing sensors and monitoring systems becomes essential to create advanced detection systems for selective sensing of toxic analytes for environmental remediation. The integration of materials with predesignated nanostructures into sensor devices, such as surface acoustic wave (SAW), quartz crystal microbalance (QCM), and QCM with dissipation (QCM-D) monitoring, has led to an immense progress in the sensing applications of toxic target analytes at the nanogram range. Here, an overview is introduced of recent advancement in the fabrication of piezoelectric devices for the interfacial mass sensing of targeted chemical vapors and ions through combination with nanoporous materials including mesoporous materials carbon-based nanomaterials, metal–organic frameworks (MOFs), MOF-derived nanoporous carbons, Prussian blue (PB) and its analogues (PBA), zeolites and related materials. Challenges and future prospect are also summarized by the advanced QCM technique associated with properties of nanostructured materials.