Superior Transport Research Articles

Phase engineering of 1 T-MoS2 on BiVO4 photoanode with p–n Junctions: Establishing high speed charges transport channels for efficient photoelectrochemical water splitting

Photoelectrochemical (PEC) conversion of solar energy into chemical energy urgently requires attractive photoelectrodes to advance its practical application. Herein, we demonstrated a simple dopant electron strategy for phase control engineering and prepared a hybrid photoelectrode of 1 T-MoS2 nanosheets sensitized monoclinic BiVO4 (denoted as 1 T-MoS2@BiVO4) with p–n junction. The internal p–n heterojunction in the composite photoanode contributes to its superior charges transport. Further, the inserted 1 T-MoS2 layer at the BiVO4/traditional co-catalysts (OECs) (OECs: FeOOH and NiOOH) interface can profoundly improve the PEC water splitting and solar conversion efficiency of BiVO4-based photoanodes. The corresponding photocurrent density of FeOOH@1T-MoS2@BiVO4 photoelectrode (4.02 mA cm−2) is 3.5 times as high as that of the pure BiVO4 electrode (1.14 mA cm−2) at 1.23 V vs reversible hydrogen electrode (RHE), accompanied by a photoconversion efficiency of 1.28% at 0.68 vs RHE. Theoretical integrated with experimental studies reveal that the insertion of an 1 T-MoS2 layer between BiVO4 and OECs facilitates the establishment of high speed transport channels for holes and electrons. Subsequently, copper phthalocyanine (CuPc) as an unconventional hole-transporting organic material could maintain the photocurrent density of the composite photoanode for stability test over 8 h. Importantly, this study sheds light on the rational design of phase-control-based devices for solar-to-chemical energy conversion, and also implies a prospective nexus between BiVO4 and traditional or unconventional co-catalysts.

X-ray CT-based numerical investigation of nickel foam-based GDLs under compression

Nickel foams feature superior structural and transport characteristics and are therefore strong candidates to be used as gas diffusion layers (GDLs) in polymer electrolyte fuel cells (PEFCs). In this work, the impact of compression on the key structural and transport properties has been investigated, including employing a specially designed compression apparatus and X-ray computed tomography. Namely, 20 equally spaced two-dimensional CT based images and numerical models have been used/developed to investigate the sensitivity of the key properties of nickel foams (porosity, tortuosity, pore size, ligament thickness, specific surface area, gas permeability and effective diffusivity) to realistic compressions normally experienced in PEFCs. Wherever applicable, the anisotropy in the property has been investigated. One of the notable findings is that, unlike porosity and ligament thickness, the mean pore size was found to decrease significantly with compression. The mean pore size is around 175 μm for uncompressed nickel foam and it decreased to around 110 μm for a 20% compression ratio and to around 70 μm for a 40% compression ratio. Further, unlike the effective diffusivity, the gas permeability was shown to be highly anisotropic with compression; this fact is of particular importance for PEFC modelling where the properties of GDLs are often assumed isotropic. All the computationally estimated properties have been presented, validated and discussed.

Darcy–Forchheimer dynamics of hybrid nanofluid due to a porous Riga surface capitalizing Cattaneo–Christov theory

Due to superior heat transport offered by hybrid nanofluids compared to traditional nanofluids, an investigation on the dynamics of a hybrid nanofluid consisting of (Fe3O4+Al2O3)/water over a porous Riga stretching surface using the double-diffusion theory of Cattaneo–Christov is investigated. The hybrid mixture (Fe3O4+Al2O3) is placed in a Darcy–Forchheimer-porous-medium, and the significance of Brownian and thermo diffusions are also taken into account. The thermophysical attributes of solid particles and base fluid are used to model the problem along with the basic transport equations of fluid dynamics. Similarity transformations are used to make the transport equations dimensionless. The final version of the coupled boundary value problem is then numerically solved via RKFST (Runge–Kutta–Fehlberg method based on shooting technique). The post-processing of the solution involves computing the velocity field, skin-friction, Nusselt number, Sherwood number, temperature field, streamlines, isotherms, and concentration field against various estimations of the involved parameters. The streamlines and isotherms are observed to be more effective for the hybrid nanofluid than the nanofluid, whereas the temperature is reduced for the hybrid nanofluid compared to the nanofluid. Temperature is reduced with the development of thermal-relaxation multiplier, while concentration is also declined with the higher estimation of concentration-relaxation multiplier.

High‐Speed Optoelectronic Graphene Sampler at 1.55 µm Reaching Intrinsic Performances

AbstractOptoelectronic sampling is the ultimate method to perform ultra‐high frequency analog‐to‐digital conversion. Thanks to the ps photo‐thermo‐bolometric effect in high mobility hexagonal boron nitride (h‐BN) encapsulated graphene, a state‐of‐the‐art optoelectronic sampler over a 40 GHz bandwidth using a 4 ps pulsed laser is demonstrated. The superior transport and optoelectronic linearities of this graphene sampler lead to very high harmonic rejections below –43 dB above 20 GHz. With a physics‐based microscopic model, it is shown that harmonics are generated by optoelectronics saturation effects and only appear when carrier energy reaches that of optical phonons, which is very high in h‐BN encapsulated graphene. This device is the first ultra‐fast optoelectronic sampler based on the bolometric effect.

Research on the calculation method of penetration resistance of bucket foundation for offshore wind turbines

The cost of foundations for offshore wind turbines constitutes approximately 35% of the total cost of an offshore wind farm. The bucket foundations show significant potential due to their superior transportation and installation efficiencies compared to pile foundations, leading to potential cost savings for the foundation of up to 30%. For a bucket foundation to be installed successfully, the penetration resistance must be predicted. However, there is currently a lack of clarity on how to select a suitable calculation method for penetration resistance based on known geological parameters to guide construction. In order to evaluate the current methods of calculation for bucket foundation penetration resistance, this study combines theoretical calculation methods with two sets of practical measurement data from the field. The calculation methods of penetration resistance for bucket foundation are first reviewed and categorized. The applicability range of each method and the parameters needed for calculation are given. Next, according to the measured data in the process of penetration of bucket foundation on site, the evolution of compartment pressure, tilt angle, resistance and required suction in the process of penetration are analyzed. Finally, the reviewed methods are compared to the results of two practical projects in order to analyze the differences between them and make recommendations for the calculation technique. The findings can be used as a guide for calculating the bucket foundation's penetration resistance in complex geological conditions.

Synthesis and characterization of tailor-made o-hydroxysubstituted anils through 1H NMR, ­13C NMR, SC-XRD and DFT studies for possible optoelectronic applications

The present work reports the synthesis of two simple tailor-made anils (o-hydroxybezylidene-orthochloroaniline & o-hydroxynaphthalidene-orthochloroaniline) and their characterization by 1H & 13C Nuclear magnetic resonance(NMR), single X-ray diffraction spectroscopy(SC-XRD) and DFT studies. DFT-B3LYP optimized the molecular structures with a 6-311G (d, p) basis set to accomplish the global minimum energy state. 1H NMR confirmed the occurrence of H-bonding between the phenolic hydrogen and azomethine nitrogen in both molecules, further supported by SC-XRD analysis and DFT studies. The structural parameters such as bond angle, bond length, and dihedral angle derived from the optimized structure of molecules with C1 symmetry were compared with the corresponding parameters extracted from the ORTEP diagrams for both anils. Appreciable harmony of the structural parameters was achieved between these two analyses, confirming the anils’ purity. Slight discrepancy observed between DFT and SC-XRD analyses was attributed to the difference in the state of the molecules. Geometric optimization indicated the molecules to be coplanar. The MEP surface and atomic charges on the atoms envisaged the electron population and charged sites of the anils. Conclusively, both the anils have a suitable structural hierarchy for superior electron transport from the phenyl rings over the entire molecular framework suitable for optoelectronics applications.

Surface embellishment accelerates the oxygen evolution reaction and removal of organic pollutant using solvothermally designed Co2O3/CuO nanocomposite

This study generates a heterostructure composed of Co2O3/CuO via a simple hydrothermal procedure as an effective OER electrocatalyst and photocatalyst. The fabricated electrode material was then analyzed to confirm the structural, morphological, and textural analysis using various methods. The nanoparticles decorated on rods nanocomposite are helpful for the electrochemical and photochemical reactions with a higher BET surface area of 112 m2 g−1. For the electrochemical investigation, CV (cyclic voltammetry), LSV (liner sweep voltammetry), EIS (electrochemical impedance), chronoamperometry, and ECSA (electrochemical active surface area) tests are performed. The fabricated electrode material showed an outstanding overpotential of 272 mV to attain 10 mA cm−2 current density, with a low Tafel value of 40 mV dec−1. The designed material is also utilized for the photodegradation of methylene blue dye with 98 % degradation under solar light and retains its stability for up to 5 cycles. The increased various active sites, more surface area, and superior charge transport properties of Co2O3/CuO explain its greater OER and degradation efficiency than its pristine oxides. The resultant material will be useful for many industrial applications in future.

Enhanced Performances of Quantum Dot Light-Emitting Diodes with an Organic–Inorganic Hybrid Hole Injection Layer

PEDOT:PSS (polyethylene dioxythiophene:polystyrenesulfonate) is a commonly used hole injection layer (HIL) in optoelectronic devices due to its high conductive properties and work function. However, the acidic and hygroscopic nature of PEDOT:PSS can be problematic for device stability over time. To address this issue, in this study we demonstrated the potential of an organic–inorganic hybrid HIL by incorporating solution-processed WOx nanoparticles (WOx NPs) into the PEDOT:PSS mixture. This hybrid solution was found to have a superior hole transport ability and low Ohmic contact resistance contributing to higher brightness (~62,000 cd m−2) and current efficiency (13.1 cd A−1) in the manufactured quantum-dot-based light-emitting diodes (QLEDs). In addition, the resulting devices achieved a relative operational lifetime of 7071 h, or approximately twice that of traditional QLEDs with PEDOT:PSS HILs. The proposed method is an uncomplicated, reliable, and low-cost way to achieve long operational lifetimes without sacrificing efficiency in optoelectronic devices.

Point-of-care applicable metabotyping using biofluid-specific electrospun MetaSAMPs directly amenable to ambient LA-REIMS.

In recent years, ambient ionization mass spectrometry (AIMS) including laser ablation rapid evaporation IMS, has enabled direct biofluid metabolome analysis. AIMS procedures are, however, still hampered by both analytical, i.e., matrix effects, and practical, i.e., sample transport stability, drawbacks that impede metabolome coverage. In this study, we aimed at developing biofluid-specific metabolome sampling membranes (MetaSAMPs) that offer a directly applicable and stabilizing substrate for AIMS. Customized rectal, salivary, and urinary MetaSAMPs consisting of electrospun (nano)fibrous membranes of blended hydrophilic (polyvinylpyrrolidone and polyacrylonitrile) and lipophilic (polystyrene) polymers supported metabolite absorption, adsorption, and desorption. Moreover, MetaSAMP demonstrated superior metabolome coverage and transport stability compared to crude biofluid analysis and was successfully validated in two pediatric cohorts (MetaBEAse, n = 234 and OPERA, n = 101). By integrating anthropometric and (patho)physiological with MetaSAMP-AIMS metabolome data, we obtained substantial weight-driven predictions and clinical correlations. In conclusion, MetaSAMP holds great clinical application potential for on-the-spot metabolic health stratification.

Hydrodynamics and OCM reaction performance in a bubbling fluidized bed reactor and a riser reactor

The reasonable reactor design is of great importance for increasing the C2 yield (C2H4 and C2H6) of the oxidative coupling of methane (OCM), and the OCM reactor should remove the heat released in reactions quickly and efficiently and minimize the consecutive reaction of ethylene to carbon oxides. The fluidized bed reactor is characterized by excellent heat transfer, superior mass transport, and large handling capacity, while fewer studies focused on large-scale fluidized bed reactors for the OCM reaction. Therefore, large cold-model experiments and computational fluid dynamics simulations were conducted to investigate hydrodynamics and the OCM reaction performance in a large-scale bubbling fluidized bed (BFB) and a large-scale riser. In the BFB reactor, consecutive reactions of ethylene are acute because of the strong gas back-mixing, high solids holdup, and non-uniform solids distribution. While the consecutive reactions of ethylene are negligible due to the plug flow structure and low solids holdup in the riser reactor. Further, both reactors can achieve isothermal operation for the OCM process. The C2 selectivity of 45.4% and C2 yield of 21.1% are obtained in the riser reactor, increasing by 20.3% and 5.8% individually than that in the BFB reactor. This study provides useful information and reference to the OCM reactor design and commercialization.

Band gap-controllable N, P co-doped carbon@ZnxCd1−xIn2S4 for photocatalytic reduction of chromium(VI) and degradation of tetracycline hydrochloride

Construction of carbon-based heterostructural photocatalyst materials with high electron transfer rates is a practical and effective strategy for the mineralization of organic pollutants and removal of toxic metal ions under visible-light irradiation. This study developed a facile hydrothermal route to prepare a series of heterojunction photocatalysts, wherein ZnxCd1-xIn2S4 nanosheets were immobilized on nitrogen and phosphorus co-doped hollow carbon spheres (N, P-C) to form N, P-C@ZnxCd1-xIn2S4 nanocomposites. Comprehensive characterization of the nanocomposites revealed that the tuning of the Zn/Cd molar ratio could effectively modulate the ZnxCd1−xIn2S4 energy band structure. Moreover, Zn0.5Cd0.5In2S4 had the most negative conduction band position and loads on non-metal-doped carbon, with superior carrier transport properties and separation efficiency. N, P-C@Zn0.5Cd0.5In2S4 (N, P-C@ZCIS2) exhibited the best photocatalytic activity for tetracycline hydrochloride degradation and Cr(VI) reduction, with rate constants of 0.04822 mg−1 min−1 and 0.14303 min−1, respectively. Notably, the photocatalysts exhibited good activity and stability even after cycle experiment. This study provides new insights into the design of carbon-based heterojunction photocatalysts for the removal of harmful chemicals.

PfCRT mutations conferring piperaquine resistance in falciparum malaria shape the kinetics of quinoline drug binding and transport.

The chloroquine resistance transporter (PfCRT) confers resistance to a wide range of quinoline and quinoline-like antimalarial drugs in Plasmodium falciparum, with local drug histories driving its evolution and, hence, the drug transport specificities. For example, the change in prescription practice from chloroquine (CQ) to piperaquine (PPQ) in Southeast Asia has resulted in PfCRT variants that carry an additional mutation, leading to PPQ resistance and, concomitantly, to CQ re-sensitization. How this additional amino acid substitution guides such opposing changes in drug susceptibility is largely unclear. Here, we show by detailed kinetic analyses that both the CQ- and the PPQ-resistance conferring PfCRT variants can bind and transport both drugs. Surprisingly, the kinetic profiles revealed subtle yet significant differences, defining a threshold for in vivo CQ and PPQ resistance. Competition kinetics, together with docking and molecular dynamics simulations, show that the PfCRT variant from the Southeast Asian P. falciparum strain Dd2 can accept simultaneously both CQ and PPQ at distinct but allosterically interacting sites. Furthermore, combining existing mutations associated with PPQ resistance created a PfCRT isoform with unprecedented non-Michaelis-Menten kinetics and superior transport efficiency for both CQ and PPQ. Our study provides additional insights into the organization of the substrate binding cavity of PfCRT and, in addition, reveals perspectives for PfCRT variants with equal transport efficiencies for both PPQ and CQ.

Mutually supportive growth strategy to engineer a hollow biochar sphere-supported TiO2 composite with improved interfacial compatibility for efficient visible light-driven photocatalysis

Improving the interfacial compatibility between active components and support is significant and challenging. Herein, a mutually supportive growth strategy was created to engineer a Fe-Cu-doped hollow biochar sphere (HBS)-supported TiO2 (TiO2/Fe-Cu-HBS) composite with strong interfacial interaction via simultaneous growth of crystalline TiO2 and epitaxial carbonization of mechanical activation-treated starch-FeCl3-CuCl2. The TiO2/Fe-Cu-HBS composite with highly dispersed distribution and embedding of spherical TiO2 particles on the Fe-Cu-HBS shell had a narrow bandgap, favorable visible light capture and absorption capability, high separation efficiency of electron–hole pairs, and high transfer efficiency of photogenerated carriers. The superior photogenerated electron transport, high specific surface area, and enriched surface oxygen vacancies led to the generation of abundant reactive radicals on TiO2/Fe-Cu-HBS under visible light stimulation, contributing to efficient photocatalytic degradation of tetracycline hydrochloride (removal rate of 95.4% within 120 min; mineralization rate of 75.3% within 180 min), rhodamine B (removal rate of 99.2% within 100 min), and carbamazepine (removal rate of 67.5% within 120 min). Moreover, TiO2/Fe-Cu-HBS maintained high photocatalytic degradation efficiency after five cycles ascribed to its favorable structural stability. A mechanism of photocatalytic degradation of tetracycline hydrochloride and possible degradation pathways were proposed. This work provides a new growth strategy for constructing highly active and stable visible light-driven TiO2-based composite photocatalysts for effectively treating organic pollutants.

PULM10: Development of a Miniaturized ECMO Device on a 3D-Printed Microfluidic Platform

Background: Risks of extracorporeal membrane oxygenation (ECMO) therapy can directly be attributed to large membrane areas and blood circuit volume. These are particularly problematic in neonates with low total blood volumes. To address this, we are developing a miniaturized prototype microfluidic ECMO using versatile 3D printing technologies and highly porous membranes. Hemolytic and O2 transport assessments of geometrical variants of the prototype design have been performed in vitro and in silico. Methods: 3D-printed flow paths and device housings were assembled with two types of membranes (PDMS and SiN) for O2 transport in water and bovine blood. The liquid was passed through single-channel geometrical prototypes of a microfluidic device with varying channel heights. O2 transport was studied by measuring dissolved O2 in water and SpO2 in blood. Numerical modeling was performed using ANSYS fluent. Results: 3D printing allows us to quickly design, build, and test design iterations. Per single pass of fluid, up to 20% increase of O2 levels for PDMS (in vitro and in silico) and 60% for SiN membranes (in silico) were observed. Reduced channel height and reduced flow rates positively affected O2 transport. Preliminary in vitro and in silico results suggest the SiN membranes have superior transport properties than the PDMS membrane. Flow rates up to 30 ml/min were achievable within a single device. Conclusion: In order to develop the Microfluidic ECMO, performance testing (O2 transport) had been performed and promising outcomes were observed for all experimental cases.

Notch-δ-doped InP Gunn diodes for low-THz band applications

The viability of the indium phosphide (InP) Gunn diode as a source for low-THz band applications is analyzed based on a notch-δ-doped structure using the Monte Carlo modeling. The presence of the δ-doped layer could enhance the current harmonic amplitude (A0) and the fundamental operating frequency (f0) of the InP Gunn diode beyond 300 ​GHz as compared with the conventional notch-doped structure for a 600-nm length device. With its superior electron transport properties, the notch-δ-doped InP Gunn diodes outperform the corresponding gallium arsenide (GaAs) diodes with up to 1.35 times higher in f0 and 2.4 times larger in A0 under DC biases. An optimized InP notch-δ-doped structure is estimated to be capable of generating 0.32-W radio-frequency (RF) power at 361 ​GHz. The Monte Carlo simulations predict a reduction of 44% in RF power, when the device temperature is increased from 300 ​K to 500 ​K; however, its operating frequency lies at 280 ​GHz which is within the low-THz band. This shows that the notch-δ-doped InP Gunn diode is a highly promising signal source for low-THz sensors, which are in a high demand in the autonomous vehicle industry.

Precise surface selenizing modulation for amorphous MoP@MoSe2/SnP2O7 hierarchical nanofibers as sodium ion battery anode

2D material with superior transport property are widely used for material improvement and modification. Among them, metal selenide holds merits of large interlayer and favorable conductivity. Possessing bigger radius of selenium and weaker M−Se bond, the conversion reaction can be more efficient compared to metal oxides and sulfides. Here, amorphous MoP@MoSe2/SnP2O7 hierarchical nanofibers was prepared through electrospinning with Se addition and its ratio adjustment during thermal treatment, the composition and surface morphology were modulated accordingly. Surprisingly, the introduction of Se can alter the distribution of Sn, and induce the formation of SnP2O7. The corresponding formation mechanism was explored via ratio and thermal treatment control. As a result, consisting of inner amorphous MoP skeleton and external conductive MoSe2/SnP2O7 layer, the material performance got greatly improved by the core–shell structure.

Flash Reforming Pyrogenic Carbon to Graphene for Boosting Advanced Oxidation Reaction

AbstractBiomass‐derived pyrogenic carbon is attractive for advanced oxidation processes (AOPs); however, its amorphous structure limits its activation efficiency. Graphene with highly conjugated π structure possesses superior electron transport ability and thus high usefulness. However, bygone strategies are scarcely effective for reforming pyrogenic carbon to graphene. Herein, for the first time, a state‐of‐the‐art flash Joule heating (FJH) technique is showcased for reforming pyrogenic carbon to 2–5‐layer graphene. FJH current‐induced ultrahigh temperature and stress field realize instantaneous (≈10 s) regeneration of pyrogenic carbon via synchronization actions of carbonization, graphitization, and exfoliation. Meanwhile, volatilization of doped N atoms accelerates graphitization but has less of an effect on graphene configuration. Accordingly, tuned oxygen groups at the graphene edge boost peroxydisulfate (PDS) adsorption for finer initiating activation. Subsequently, 2D graphene with excellent electron utilization rate strengthens hydroxyl radical and direct electron transfer pathways in activating PDS for sulfamethoxazole (SMX) degradation. Impressively, the SMX degradation efficiency by fabricated graphene raises ≈8.9‐fold as compared with pristine pyrogenic carbon. Additionally, fabricated graphene is more efficient in PDS activation than commercial metal catalysts. Undoubtedly, this study realizes effective transformation of pyrogenic carbon to graphene for highly efficient metal‐free carbocatalyst.

Cells sorted off hiPSC-derived kidney organoids coupled with immortalized cells reliably model the proximal tubule

Of late, numerous microphysiological systems have been employed to model the renal proximal tubule. Yet there is lack of research on refining the functions of the proximal tubule epithelial layer—selective filtration and reabsorption. In this report, pseudo proximal tubule cells extracted from human-induced pluripotent stem cell-derived kidney organoids are combined and cultured with immortalized proximal tubule cells. It is shown that the cocultured tissue is an impervious epithelium that offers improved levels of certain transporters, extracellular matrix proteins collagen and laminin, and superior glucose transport and P-glycoprotein activity. mRNA expression levels higher than those obtained from each cell type were detected, suggesting an anomalous synergistic crosstalk between the two. Alongside, the improvements in morphological characteristics and performance of the immortalized proximal tubule tissue layer exposed, upon maturation, to human umbilical vein endothelial cells are thoroughly quantified and compared. Glucose and albumin reabsorption, as well as xenobiotic efflux rates through P-glycoprotein were all improved. The data presented abreast highlight the advantages of the cocultured epithelial layer and the non-iPSC-based bilayer. The in vitro models presented herein can be helpful in personalized nephrotoxicity studies.

Nonfullerene Agent Enables Efficient and Stable Tin‐Based Perovskite Solar Cells

Tin‐based perovskites have emerged as the most promising lead‐free perovskite materials due to the characteristics of the environmentally friendly and more suitable bandgap. However, the power conversion efficiency still lags behind the lead perovskite owing to unfavorable defects of the perovskite film and poor interface contact between tin perovskite and electron transporting layers. Herein, an n‐type conjugated nonfullerene molecule, termed IO‐4Cl, is developed for efficient and stable tin perovskite solar cells (TPSCs). The IO‐4Cl possesses electron‐donating functional groups that can enlarge grain size and passivate defect states of perovskite films through Lewis acid–base interactions. Besides, the IO‐4Cl exhibits an appropriate lowest unoccupied molecular orbital level and interface‐modification ability, enabling superior electron extraction and transport ability of TPSCs. More importantly, the hydrophobic characteristic of IO‐4Cl prevents the decomposition of perovskite films under moisture conditions, improving the moisture stability of TPSCs. Consequently, the TPSCs with IO‐4Cl achieve a champion efficiency of 11.49% with an open‐circuit voltage increase of 100 mV, and excellent moisture stability under ambient air condition with 30% relative humidity, without encapsulation. The work provides a new inspiration for the introduction of functional nonfullerene materials to obtain highly efficient and stable TPSCs.

Railways Passengers Comfort Evaluation through Motion Parameters: A Systematic Review

Railways are one of the most widely used mass transportation systems. Its superior transportation capacity, low environmental impact, high safety, and comfort have been leading to a continuous increase in passengers. To keep this trend going, it is crucial to improve the railways’ attractiveness and comfort levels. A rail journey’s comfort performance is rather complex, involving the analysis of multiple factors. Those raised by the vehicle motion and seat performance are the focus of vehicle designers’ concerns. Therefore, only a combination of static and dynamic comfort methodologies can accurately characterize passengers’ comfort. This work aimed to perform a systematic review concerning the comfort evaluation of train passengers. The bibliographic search yielded 62 studies on static and dynamic comfort evaluation methods. Results show a lack of experiments conducted on real rail environments, leading to weak conclusions regarding the real in-service conditions that train users face. Moreover, an investigation gap concerning the simultaneous application of both static and dynamic methodologies was observed. Therefore, more investigations are needed to evaluate and increase passengers’ comfort and promote rail usage as a daily transportation system.