Direct Charge Research Articles

Predicting the Heat Generation Rate in Large Format Pouch-Type Lithium-Ion Battery Cells for Automotive Applications

Accurate prediction of the heat generation rate of lithium ion batteries is critical for driving towards a cost effective and efficient design of a thermal management system for various applications.[1, 2] because of the increase in battery cell dimensions associated with an increase in battery cell capacity to drive towards a reduction in range anxiety for automotive applications, as well as more aggressive operating conditions that are typically seen in the automotive industry, such as direct current fast charge and sustained driving under load, heat generation at the cell level must be considered as spatially nonuniform during operation. Proper design of the thermal management system requires prediction[3] of the heat generation of the battery cell in both a lumped fashion for system sizing, as well as a distributed mode in order to focus cooling appropriately to decrease local temperature extremes. Local temperature extremes can adversely affect the aging of the battery cell due to the non-uniformities in electrochemical utilization of the active material, increased local reaction rates, and increased mechanical stresses in active materials.In this work, we detail our efforts to characterize the heat generation[4] of a battery cell under a variety of operating conditions, quantify the impact of temperature non-uniformities[5] on the aging of the battery cell, and experimentally[6, 7] evaluate the localized aging in the battery electrodes based on local temperature conditions. Here, we will describe the modeling methods developed to link operating conditions, aging, and heat generation with the electrochemical performance of the battery cell. A discussion of the model performance for relevant automotive applications will also be included.References M. Song, Y. Hu, S.-Y. Choe and T. R. Garrick, J Electrochem Soc, 167, 120503 (2020).Y. Hu, S.-Y. Choe and T. R. Garrick, Electrochim Acta, 362, 137124 (2020).M. Song, Y. Hu, S.-Y. Choe and T. R. Garrick, J Electrochem Soc, 169, 070502 (2022).Y. Hu, S.-Y. Choe and T. R. Garrick, Applied Thermal Engineering, 189, 116709 (2021).Y. Hu, S.-Y. Choe and T. R. Garrick, J Power Sources, 532, 231350 (2022).U. Janakiraman, T. R. Garrick and M. E. Fortier, J Electrochem Soc, 167, 160552 (2020).T. R. Garrick, J. Gao, X. Yang and B. J. Koch, J Electrochem Soc, 168, 010530 (2021).

(Invited) Plasmonic Enhancement of Electrochemical Reactions Using LSPR Phenomenon

Using Localized Surface Plasmon Resonance Effect for Enhancing Electrochemical reactions has been reported earlier both in terms of direct electron injection/transfer (DET) in outer-sphere reductive processes as well as charge injection into semiconductors via plasmon-induced resonant electron transfer processes (PIRE). While the former (DET) is mostly influenced by the lifetimes of the ejected hot electrons and their rapid cooling at the interface. For inner sphere reductive processes via the LSPR phenomenon, direct charge injection into the LUMO states of the adsorbed species is required. In this regard, it is imperative to distinguish between the inter-band charge transfer of the adsorbed species because of exposure to photons. In contrast to these charge injection into semiconductors via plasmon-induced resonant electron transfer processes (PIRE) is less understood and more complex. In this presentation, we will use the well-known endothermic anodic oxygen evolution reaction (OER) in alkaline pH to showcase fundamental aspects of charge injection and its effect on the hole-driven OER mechanism. For this well know OER catalyst, layered double hydroxides of Ni with Fe and Co dopants will be used. Electrochemical enhancement of OER will be explained based on detailed structural motifs of the semiconductors its band structure and the resonance effect of Au induced by the LSPR effect. The presence of direct and Indirect bandgaps will be discussed in the context of three possible mechanisms: (i) Charge carriers are directly injected via LSPR into the semiconductor. The conduction band of the semiconductor is usually (-0.1 to 0.0 eV vs. NHE) and the valence band is between (2.00 and 3.5 eV) which corresponds to electron energy between -2.00 to 3.5 eV vs NHE. For LSPR nanoparticles SPR energy is between 1.0 and 4.0 eV. Also, the Fermi energy of LSPR is usually 0.0 vs. NHE. Hence LSPR only enables energetic electrons to be transferred from metals to semiconductors. It is the interface between LSPR and the semiconductor which is important. Charge injection is more prevalent when metal LSPR is of lower energy than the semiconductor. Direct electron transfer (DET). (ii) Transfer not involving direct electron injection but via (a) near field electromagnetic and (b) resonant photon scattering mechanism. This has been shown to work by adding a thin dielectric material between the LSPR and semiconductor. This would be most likely in the case of OER where surface localized plasmons will be the most important determinant as opposed to recombination events in the bulk of the semiconductor. This is most important for OER as it depends on the surface hole concentration. It should be noted that larger nanoparticles (>50 nm) have increased resonant photon scattering. Such a mechanism is more prevalent when we have an overlap between metal LSPR and semiconductor bands leading to plasmon induced resonant electron transfer (PIRET). (iii) When metal LSPR is in direct contact with the semiconductor all three phenomenon could be active.

Rational construction of g-C3N4/SnO2/CoFe2O4 dual Z-scheme system as a potential scaffold for fluorescence sensing and visible light driven photocatalytic degradation of lethal pollutants

Mimicking the natural photosynthesis process, novel direct dual Z-scheme CN/SnO2/CoFe2O4 heterostructures with different weight ratios (CN/SnO2:CoFe2O4 be 1:1, 2:1 and 1:2; namely CSnCo-1, CSnCo-0.5 and CSnCo-2, respectively) were successfully fabricated and employed for photocatalytic degradation of anthracycline drug, doxorubicin (DXR) and aromatic compound, p-nitrophenol (PNP) and fluorescence detection of heavy metal ion, Hg2+; DXR and PNP. CSnCo-0.5 displayed exceptional photocatalytic capability having pseudo first order rate constant values 5.60, 3.02, 1.23 and 1.38 times higher for DXR; and 4.2, 3.0, 1.18 and 1.12 times higher for PNP in comparison to CN, CSn-20, CSnCo-1 and CSnCo-2, respectively. UV–vis DRS study, photoluminescence spectra and electrochemical impedance results inveterate the formation of direct dual Z-scheme charge transfer, which is beneficial for boosting photocatalytic performance of the system. Additionally, CSnCo-0.5 proved to be highly selective and sensitive for the FL sensing of Hg2+, DXR and PNP with detection limits as low as 0.57 µM, 0.05 µM and 0.63 µM, respectively. Further, sensor provided good analytical performance in real water samples.

Correlating the Hybridization of Local‐Exciton and Charge‐Transfer States with Charge Generation in Organic Solar Cells

AbstractIn organic solar cells with very small energetic‐offset (ΔELE − CT), the charge‐transfer (CT) and local‐exciton (LE) states strongly interact via electronic hybridization and thermal population effects, suppressing the non‐radiative recombination. Here, we investigated the impact of these effects on charge generation and recombination. In the blends of PTO2:C8IC and PTO2:Y6 with very small, ultra‐fast CT state formation was observed, and assigned to direct photoexcitation resulting from strong hybridization of the LE and CT states (i.e., LE‐CT intermixed states). These states in turn accelerate the recombination of both CT and charge separated (CS) states. Moreover, they can be significantly weakened by an external‐electric field, which enhanced the yield of CT and CS states but attenuated the emission of the device. This study highlights that excessive LE‐CT hybridization due to very low , whilst enabling direct and ultrafast charge transfer and increasing the proportion of radiative versus non‐radiative recombination rates, comes at the expense of accelerating recombination losses competing with exciton‐to‐charge conversion process, resulting in a loss of photocurrent generation.

Bonding Analysis of the Ge‐Ge Bonds in the Octagermacubane Ge8(Sit‐butyl2methyl)6

AbstractQuantum chemical calculations have been carried out at the BP86/def2‐SVP level on Ge8(Sit‐butyl2methyl)6(1) and the bonding situation has been analyzed with a variety of methods. The calculated equilibrium geometry of1is in good agreement with the reported x‐ray structure analysis. The D3 correction for dispersion interactions as a sum of pairwise attractions leads to an overestimate of the effect of dispersion forces. Calculations at BP86‐D3(BJ)/def2‐SVP give shorter bonds for Ge(I)−Ge(I) than for Ge(0)−Ge(I), which is in contrast to the experimental values and the BP86/def2‐SVP results. The NBO analysis suggests that the best Lewis structure of1has lone‐pair orbitals at the Ge(0) atoms with occupation numbers of 1.70 e. A lone‐pair character at Ge(0) albeit with less weight is also suggested by the shape of the HOMO, which is an antibonding orbital between the Ge(0) atoms with small contributions from the Ge(I) atoms. The LUMO of1is the corresponding bonding combination of the Ge(0) AOs, which can be explained with the reluctance of the heavier main‐group atoms to s/p hybridization of the valence orbitals. The calculated bond order values suggest significant direct Ge(0)−Ge(0) interactions. This is supported by the shape of the HOMO and by the results of EDA‐NOCV calculations. The deformation densities and the orbitals associated with the pairwise orbital interaction show that there is a direct charge flow between the Ge(0) atoms of the two fragments, but it is not completely separated from the Ge(0)−Ge(I) and Ge(I)−Ge(I) bond formation. The QTAIM calculations suggest that1has a cubic structure with a cage critical point but not a bond critical point for the Ge(0)−Ge(0) interactions. The dispersion interactions of the large substituents in1have a significant influence on the stability of the compound.

Photocatalytic water splitting in the gap between plasmonic gold nanoclusters

Plasmon-mediated photocatalytic water splitting holds promise for efficient solar energy harvesting. Experimental studies have shown that “hot spots” in an assembly of plasmonic nanoclusters, which is the real case for practical applications, are beneficial for photocatalysis, but the interactions between different nanoclusters are difficult to observe by experimental techniques. Theoretical studies, however, have employed the model with a water molecule adsorbed on a single plasmonic metal nanocluster. Here, we employed the representative model of a water molecule placed in the gap between two gold nanoclusters and computationally investigated the effects of the configurations of plasmonic nanoclusters on plasmon-mediated water splitting. Results show that the hot electron transfer mode can be tuned by the plasmonic configurations. Compared to the configuration with only one gold nanocluster, more significant contribution of direct charge transfer was observed for the configuration with two gold nanoclusters, which is attributed to a stronger field enhancement; as a result, the water splitting rate was also enhanced. Results also demonstrate a charge transfer chain from one gold nanocluster to the water molecule and then to the other gold nanocluster, which is tunable by the distances between the water molecule and the gold nanoclusters. This charge transfer chain significantly affected the amount of hot electrons accumulated on the water molecule. Caused by this, the configuration where the water molecule was placed right at the center of the two gold nanoclusters, i.e., the configuration corresponding to the strongest field enhancement, was surprisingly not the most favorable one for the reaction.

An effectiveness and economic analyses of tricalcium phosphate combined with iliac bone graft versus RhBMP-2 in single-level XLIF surgery in Thailand

Study designRetrospective study.ObjectivesTo perform effectiveness and economic analyses using data from a retrospective study of patients who underwent XLIF surgery using tricalcium phosphate combined with iliac bone graft (TCP + IBG) or BMP-2 in Thailand.MethodsData were collected from retrospective review of the medical charts and the spine registry of Siriraj Hospital, Bangkok, Thailand. The patients were divided into two groups (TCP + IBG group and BMP-2 group). Demographic, perioperative data, radiographic, clinical results, and quality of life related to health were collected and analyzed at 2-year follow-up. All economic data were collected during the perioperative period and presented as total charge, bone graft, implant/instrumentation, operative service, surgical supply, transfusion, medication, anesthesia, laboratory, and physical therapy.ResultsTwenty-five TCP + IBG and 30 BMP-2 patients with spondylolisthesis and spinal stenosis as primary diagnosis were included. There were no significant differences in all demographic parameters (gender, age, underlying disease, diagnosis, and level of spine) between these two groups. During the perioperative period, the TCP + IBG group had more mean blood loss and more postoperative complications compared to the BMP-2 group. At 2 years of follow-up, there were no significant differences between the radiographic and clinical outcomes of the TCP + IBG and BMP-2 groups. The fusion rate for TCP + IBG and BMP-2 at 2 years of follow-up was 80% and 96.7%, respectively, and no statistically significant differences were observed. All clinical outcomes (Utility, Oswestry Disability Index, and EuroQol Visual Analog Scale) at 2-year follow-up improved significantly compared to preoperative outcomes, but there were no significant differences between the TCP + IBG and BMP-2 groups, either at preoperatively or at 2-year follow-up. The total charge of TCP + IBG was statistically significantly lower than that of BMP-2. Furthermore, the charges of TCP + IBG and BMP-2 during the perioperative period in Thailand were up to three times less than those in the United States.ConclusionsUsing TCP + IBG as a standalone bone substitution for XLIF surgery with additional posterior instrumentation resulted in significantly lower direct medical charge compared to those using BMP-2 in the perioperative period. However, we could not detect a difference in the long-term radiographic and clinical outcomes of patients with TCP + IBG and BMP-2. These suggest that TCP + IBG may be a valuable alterative bone graft, especially in low- and middle-income countries.

Plasmon-Mediated Hydrogen Dissociation with Symmetry Tunability.

The atomic-scale mechanism of plasmon-mediated H2 dissociation on gold nanoclusters is investigated using time-dependent density functional theory. The position relationship between the nanocluster and H2 has a strong influence on the reaction rate. When the hydrogen molecule is located in the interstitial center of the plasmonic dimer, the hot spot here has a great field enhancement, which can promote dissociation effectively. The change in the molecular position results in symmetry breaking, and the molecular dissociation is inhibited. For the asymmetric structure, direct charge transfer from the gold cluster to the antibonding state of the hydrogen molecule by plasmon decay makes a prominent contribution to the reaction. The results provide deep insights into the influence of structural symmetry on plasmon-assisted photocatalysis in the quantum regime.

Structure determination of a low-crystallinity covalent organic framework by three-dimensional electron diffraction

Covalent organic frameworks (COFs) have been attracting intense research due to their permanent porosity, designable architecture, and high stability. However, COFs are challenging to crystallize and their synthesis often results in tiny crystal sizes and low crystallinities, which hinders an unambiguous structure determination. Herein, we demonstrate that the structure of low-crystallinity COF Py-1P nanocrystals can be solved by coupling three-dimensional electron diffraction (3DED) with simulated annealing (SA). The resulting model is comparable to that obtained from high-crystallinity samples by dual-space method. Moreover, for low-resolution 3DED data, the model obtained by SA shows a better framework than those provided by classic direct method, dual-space method, and charge flipping. We further simulate data with different resolutions to understand the reliability of SA under different crystal quality conditions. The successful determination of Py-1P structure by SA compared to other methods provides new knowledge for using 3DED to analyze low-crystallinity and nanosized materials.

Flexible Synergistic MoS2 Quantum Dots/PEDOT: PSS Film Sensor for Acetaldehyde Sensing at Room Temperature.

Acetaldehyde (CH3CHO) is known as a primary carcinogen, and the development of wearable gas sensors for its detection at room temperature has rarely been rarely reported. Herein, MoS2 quantum dots (MoS2 QDs) have been employed to dope with poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT: PSS) via a simple in situ polymerization technique, and the CH3CHO gas-sensing properties of the resultant flexible and transparent film were investigated. MoS2 QDs had been evenly dispersed into the polymer, and it was shown that PEDOT: PSS doped with the 20 wt % MoS2 QDs sensor exhibited the highest response value of 78.8% against 100 ppm CH3CHO and its detection limit reached 1 ppm. Moreover, the sensor response remained stable for more than 3 months. In particular, the different bending angles (from 60 to 240°) had little effect on the sensor response to CH3CHO. The possible reason for the enhanced sensing properties was attributed to the large number of reaction sites on the MoS2 QDs and the direct charge transfer between the MoS2 QDs and PEDOT: PSS. This work suggested a platform to inspire MoS2 QDs-doping PEDOT: PSS materials as wearable gas sensors for highly sensitive chemoresistive sensors to detect CH3CHO at room temperature.

Applying Copolymerization Kinetics to Understand and Optimize Swelling Responses in Superabsorbent Hydrogels

While acrylic acid (AA)-based superabsorbent hydrogels (SAHs) have been widely used in multiple applications, the effects of counterion condensation and the polyelectrolyte effect at suppressing the effective degree of ionization in such systems limit their superabsorbency. Herein we describe the use, and investigate the mechanism, of sulfate comonomers containing different types of polymerizable functional groups for increasing the superabsorbency of acrylic acid-based SAHs. Specifically, acrylamido-2-methylpropanesulfonic acid (AMPS), 3-sulfopropyl acrylate (SPAK), and 3-sulfopropyl methacrylate (SPMK) sulfated monomers featuring similar distances between the polymer backbone and the sulfate group but different polymerizable groups were copolymerized with acrylic acid to fabricate SAHs. Measurements of the effective homopolymerization rate constants and copolymerization ratios associated with each copolymerization enabled the prediction of the relative chain distributions of monomers in each copolymer, as quantified by the blockiness parameter (i.e., the instantaneous or average number of consecutive monomers of each type polymerized). While all sulfated comonomers significantly enhanced swelling relative to an acrylic acid control, copolymers in which longer AA blocks are produced (AA-AMPS) resulted in lower swelling than copolymers in which shorter AA blocks are produced (AA-SPAK, AA-SPMK), a result attributed to the suppressed polyelectrolyte effect in copolymers with shorter AA blocks. The formation of limited length blocks of the sulfated monomer SPMK showed additional benefits for enhancing swelling, consistent with enhanced direct charge–charge repulsion between fixed charges in such copolymer systems. We anticipate this linkage between copolymerization kinetics and swelling properties offers the potential to enable improved rational design of superabsorbent hydrogels with higher sorbency.

Simultaneous photocatalytic tetracycline oxidation and Cr(VI) reduction by a 0D/3D hierarchical Bi2WO6@CoO Z-scheme heterostructure: In situ interfacial engineering and charge regulation mechanism

Constructing visible-light driven semiconductor heterojunction with high redox bifunctional characteristics is a promising approach to deal with the increasingly serious environmental pollution problems, especially the coexistence of organic/heavy metal pollutants. Herein, a simple in-situ interfacial engineering strategy for the fabrication of 0D/3D hierarchical Bi2WO6@CoO (BWO) heterojunction with an intimate contact interface was successfully developed. The superior photocatalytic property was reflected not only in individual tetracycline hydrochloride (TCH) oxidation or Cr(VI) reduction, but also in their simultaneous redox reaction, which could be predominantly attributed to the outstanding light-harvesting, high carrier separation efficiency and enough redox potentials. In the simultaneous redox system, TCH acted as a hole-scavenger for Cr(VI) reduction, replacing the additional reagent. Interestingly, superoxide radical (·O2−) played the role as oxidants in TCH oxidation but as electron transfer media in Cr(VI) reduction. On account of the interlaced energy band and tight interfacial contact, a direct Z-scheme charge transfer model was established, which was verified by the active species trapping experiments, spectroscopy, and electrochemical tests. This work provided a promising strategy for the design/fabrication of highly efficient direct Z-scheme photocatalysts in environmental remediation.

Peculiarities of One Narrative− on Holocaust, without Metaphors (based on The Boy in the Striped Pyjamas by John Boyne)

The purpose of our article is to show through John Boyne's well-known novel The Boy in the Striped Pajamas,2006, the lexical-semantic and also the stylistic devices chosen by the writer when he tells us about one of the greatest catastrophes of mankind - the Holocaust. We tried to highlight the writer's style: his choice gives the impression that this horrible event is beyond being described by metaphors. The narrative is straightforward, concise, and mostly devoid of direct emotional charge since the Holocaust itself has become a powerful metaphor for this dreadful humanitarian catastrophe. The story told by the writer is a story experienced through the eyes and mind of a nine-year-old boy, Bruno. Our research aims at revealing those linguistic units − "signifiers", with their specific syntactic, phonetic, lexical-semantic and also stylistic characteristics, which the writer uses for narration. Their functional load is diverse: sometimes, with this or that wisely chosen signifier, the writer shows the possibilities of phonetically different "reading" of this or that word. e.g. "Fury" instead of "Führer"; Sometimes with childish naivety and misunderstanding of the wrongly perceived name: "Out-with" instead of "Auschwitz". We also had a very interesting case when the writer sometimes uses euphemistic expressions to cover what he did not mean to say directly. Similar linguistic units abound throughout the novel, turning the entire text into a homogeneous linguistic fabric. It is also interesting to note the fact that each chapter is titled in a way that suits the nature of the narrative: they also suggest childish logic and thinking. By taking into consideration these lingusitic qualities of the novel, we presume that the article will be interesting for readers interested in psycho-linguistics as well.

Passivating Perovskites in Air Via an Alternating Cation Interlayer Phase Formed by Benzylamine Vapor Fumigation

Abstract2D perovskites are widely employed to improve efficiency and stability of perovskite solar cells (PSCs), but the processes are rarely accomplished in air due to the difficulty of controlling the formation processes. An ultra‐thin 2D capping layer with an alternating cation interlayer (ACI) structure is in situ formed by fumigating 3D perovskites with benzylamine vapor. The whole process is finished in air within 10 s regardless of the humidity, after which both defects and tensile strain are reduced and the interfacial energy band gets benignly aligned to a type‐I heterojunction, avoiding direct charge recombination at the interface. Theoretical analysis reveals that the ACI phase is thermodynamically more stable than an analogous Ruddlesden–Popper phase. The strategy can passivate various perovskites, including methylammonium (or multi‐cation) lead (or lead/tin mixed) halide perovskites, prepared via either vapor or solution approaches, increasing the absolute power conversion efficiency by up to 2.5%. It can uniformly passivate PSCs without area limitation, and provide a repeatable methodology for passivating perovskites.

Modification of WO3 photoanode with NiFe-LDHs nanosheets array for efficient Photoelectrocatalytic removal of tetracycline

A novel WO3@NiFe-LDHs photoanode was successfully synthesized by electrochemical depositing NiFe-LDHs nanosheets array on the surface of nanoplate WO3 photoanode, in which NiFe-LDHs nanosheets formed a hetero-junction with WO3 and offered mass transfer sites to improve the bulk and interfacial charge separation of WO3@NiFe-LDHs photoanodes. In addition, TC was captured by NiFe-LDHs nanosheets, which not only facilitated the direct charge transfer for TC degradation, but also induced TC to be photo-sensitizer to enhance the light absorbance of WO3@NiFe-LDHs photoanode. Moreover, NiFe-LDHs nanosheets acted as surface catalytic sites for accelerating the water activation to generate highly oxidizing •OH. Therefore, the optional WO3@NiFe-LDHs2.5 photoanode displayed the highest PEC removal of TC with a degradation percentage of 92.3% and total organic carbon removal of 70.4% at 0.6 V (vs Ag/AgCl) bias, and showed higher photocurrent density compared with pristine WO3 photoanode. Furthermore, WO3@NiFe-LDHs photoanode showed favorable stability in the PEC degradation process, and TC was finally mineralized into CO2, H2O and some small molecular products. This work provides a deep insight on the modification of interfacial reaction to enhance the PEC degradation performance, which offered a potential route for designing PEC system with the concept of treating pollution with pollution.

Electro- and Photoinduced Interfacial Charge Transfers in Nanocrystalline Mesoporous TiO2 and TiO2/Iron Porphyrin Sensitized Films under CO2 Reduction Catalysis.

Electro- and photochemical CO2 reduction (CO2R) is the quintessence of modern-day sustainable research. We report our studies on the electro- and photoinduced interfacial charge transfer occurring in a nanocrystalline mesoporous TiO2 film and two TiO2/iron porphyrin hybrid films (meso-aryl- and β-pyrrole-substituted porphyrins, respectively) under CO2R conditions. We used transient absorption spectroscopy (TAS) to demonstrate that, under 355 nm laser excitation and an applied voltage bias (0 to -0.8 V vs Ag/AgCl), the TiO2 film exhibited a diminution in the transient absorption (at -0.5 V by 35%), as well as a reduction of the lifetime of the photogenerated electrons (at -0.5 V by 50%) when the experiments were conducted under a CO2 atmosphere changing from inert N2. The TiO2/iron porphyrin films showed faster charge recombination kinetics, featuring 100-fold faster transient signal decays than that of the TiO2 film. The electro-, photo-, and photoelectrochemical CO2R performance of the TiO2 and TiO2/iron porphyrin films are evaluated within the bias range of -0.5 to -1.8 V vs Ag/AgCl. The bare TiO2 film produced CO and CH4 as well as H2, depending on the applied voltage bias. In contrast, the TiO2/iron porphyrin films showed the exclusive formation of CO (100% selectivity) under identical conditions. During the CO2R, a gain in the overpotential values is obtained under light irradiation conditions. This finding was indicative of a direct transfer of the photogenerated electrons from the film to absorbed CO2 molecules and an observed decrease in the decay of the TAS signals. In the TiO2/iron porphyrin films, we identified the interfacial charge recombination processes between the oxidized iron porphyrin and the electrons of the TiO2 conduction band. These competitive processes are considered to be responsible for the diminution of direct charge transfer between the film and the adsorbed CO2 molecules, explaining the moderate performances of the hybrid films for the CO2R.

Application of BiOX Photocatalyst to Activate Peroxydisulfate Ion-Investigation of a Combined Process for the Removal of Organic Pollutants from Water

The persulfate-based advanced oxidation processes employing heterogeneous photocatalysts to generate sulfate radicals (SO4•−) from peroxydisulfate ion (PDS, S2O82−) have been extensively investigated to remove organic pollutants. In this work, BiOX (X = Cl, Br, and I) photocatalysts were investigated to activate PDS and enhance the transformation rate of various organic substances under UV (398 nm) and Vis (400–700 nm) radiation. For BiOCl and BiOBr, in addition to excitability, the light-induced oxygen vacancies are decisive in the activity. Although without organic substances, the BiOI efficiency highly exceeds that of BiOBr and BiOCl for PDS activation (for BiOI, 15–20%, while for BiOBr and BiOCl, only 3–4% of the PDS transformed); each BiOX catalyst showed enhanced activity for 1,4-hydroquinone (HQ) transformation due to the semiquinone radical-initiated PDS activation. For sulfamethoxypyridazine (SMP), the transformation is driven by direct charge transfer, and the effect of PDS was less manifested. BiOI proved efficient for transforming various organic substances even under Vis radiation. The efficiency was enhanced by PDS addition (HQ is wholly transformed within 20 min, and SMP conversion increased from 40% to 90%) without damaging the catalyst; its activity did change over three consecutive cycles. Results related to the well-adsorbed trimethoprim (TRIM) and application of biologically treated domestic wastewater as a matrix highlighted the limiting factors of the method and visible light active photocatalyst, BiOI.

Design of lateral and vertical Bi4O5I2/BiOCl heterojunctions with different charge migration pathway for efficient photoredox activity

As 2D heterojunction photocatalysts, lateral heterojunctions (LHs) formed based on chemical bonding generally exhibit much higher photocarrier separation efficiency than vertical heterojunctions (VHs) formed by van der Waals bonds. However, little is known about the different detailed interfacial structures and photocarrier separation mechanisms of the two heterojunctions. Herein, 2D BiOCl and Bi4O5I2 were selected as model building blocks to construct BiOCl/Bi4O5I2 VHs and LHs. The LHs with direct charge carrier transport channels show stronger interfacial electric field and higher charge transfer efficiency than the VHs. The photogenerated charge carrier migration pathway in the LHs follows a Z-scheme model, while the VHs fits a type II model. As a result, the BiOCl/Bi4O5I2 LHs exhibited higher redox performance than the VHs, which is 1.55, 1.56 and 2.1 times better for H2 production, Cr(VI) photoreduction and phenol photodegradation, respectively. This study demonstrates a new approach to constructing highly efficient facet-dependent 2D heterojunction photocatalysts.

Corrections to “Direct Charge Control for Mixed Conduction Mode Grid-Connected Inverter” [Jan 23 316-331

Unfortunately, due to omissions in the proof of the paper, Figs. 10(c), 16, 22, 27(a) and (b), and 30 have some mistakes that confuse the normal reading.

An Unprecedented Strategy to Fabricate Inside/Surface Homojunction in Bismuth Oxychloride for Efficient Photocatalysis

The design of an efficient homojunction in bismuth oxychloride via simple means is still challenging. Herein, an inside/surface homojunction of bismuth oxychloride via fabricating surface-layer oxygen vacancies from a sulfur dopant and surface-layer hydroxyl from an alkali modification (BOCSO) in a one-pot hydrothermal process is successfully prepared. BOCSO exhibits enlarged specific surface area, improved adsorption of substrate, and enhanced photogenerated charge separation and transfer efficiencies. Extensive characterizations and density functional theory (DFT) calculations demonstrate BOCSO can form a defect level via surface oxygen vacancies and S doping to narrow the energy gap and capture the photogenerated electrons and holes. Meanwhile, both oxygen vacancies and hydroxyls on the BOCSO surface can also form an inside/surface homojunction containing an interfacial electric field (IEF) to induce a direct Z-scheme charge transfer mechanism. Taking advantage of the above, the photocatalytic degradation activity is remarkably elevated compared to that of pristine BiOCl (BOC). This work provides a new strategy for the fabrication of an inside/surface homojunction in bismuth oxychloride via novel surface modification engineering.