High Separation Rate Research Articles

Vacancy defect and piezoelectric field assisted photocatalytic performance of BiO(Cl1/3Br1/3I1/3)x for the degradation of organic pollutants

Semiconductor photocatalysts have been widely researched in wastewater treatment of organic dyes, among which bismuth halide semiconductors have shown great application prospects due to their unique layered structure and diverse micromorphology. As for photocatalysis, high concentration of photo-generated carriers and their effective separation are considered to be the key to obtain excellent photocatalytic performance. In view of the common issues of high bandgap energy and low carrier separation rate in bismuth halide, in this paper, the BiO(Cl1/3Br1/3I1/3)x catalysts with different proportions of Bi3+ and (Cl1/3Br1/3I1/3)- were designed and synthesized by hydrothermal method, through constructing hybrid energy levels and thus accomplishing by multi-halogen doping to widen the light absorption range. For another, the efficient separation of electrons and holes was achieved in BiO(Cl1/3Br1/3I1/3)x in virtue of a built-in field stemmed from the intrinsic piezoelectric effect, and band tilting. Meanwhile, more active sites were induced by Vo•• and VBiʹʹʹ due to the directional impact of the built-in field. Ultimately, BiO(Cl1/3Br1/3I1/3)5/7 demonstrated the optimum catalytic performance under the combined light irradiation and ultrasonic vibration, with the degradation efficiency of MB reaching 91.28% in 60 min and the k of 0.0360 min-1, and 97.44% degradation efficiency of Rh B within 18 min and the k of 0.1565 min-1 together with excellent cycling stability. The prepared BiO(Cl1/3Br1/3I1/3)5/7 catalyst has a huge application potential for the degradation of wastewater, taking full advantage of environmental vibration energy and light energy.

Cation selectivity during flow electrode capacitive deionization

Efficient separation of specific ions from aqueous media is crucial for advanced water treatment and resource recovery. Flow electrode capacitive deionization (FCDI) offers potential for selective ion removal through continuous operation. This study evaluates the performance of selective cation separation using a commercial activated carbon slurry in a multi-ion solution of monovalent (Li+, Na+, K+) and bivalent (Ca2+, Mg2+) cations. We assess ion removal and cation selectivity under different operational parameters, such as applied potential, slurry flow rate, and feed water flow rate. Our data show that bivalent cations, namely Ca2+ and Mg2+, are preferentially removal due to their higher charge-to-size ratio, aligning with hydrated ion sizes. The highest separation rate was observed for Ca2+ (5.7 μg cm−2 min−1), and the lowest for Li+ (0.2 μg cm−2 min−1). At the highest applied voltage (1.2 V), charge efficiencies reached 70 %, with an energy consumption of 41 Wh mol−1 for nearly complete cation removal. Optimal conditions were identified with a slurry flow rate of 6 mL min−1, feed water flow rate of 2 mL min−1, activated carbon content of 10 mass%, 1 mass% carbon black, and a cell voltage of 1.2 V. These findings highlight the importance of optimizing operational parameters to enhance ion removal.

A p-n heterojunction PdO/CeO2 photocatalysts with enhanced photocatalytic ability for reduction of Hg(II) ions from aqueous solution

Heterostructured photocatalysts represent an essential role in the catalytic redox reactions in wastewater during illumination. In this contribution, p-n heterojunction PdO/CeO2 photocatalysts were constructed with enhanced photocatalytic ability for the reduction of Hg(II) utilizing HCOOH as hole scavengers under visible light. PdO NPs were uniformly spread on the mesoporous CeO2 surface, to act as potential separation centers of electrons and holes. The synthesized PdO/CeO2 nanocomposites exhibited an excellent photocatalytic ability, contrasted to the bare CeO2 NPs. The photocatalytic ability of PdO/CeO2 nanocomposites for reduction of Hg(II) has existed in the trends of 2%PdO ≥1.5%PdO >1%PdO >0.5 % PdO/CeO2 nanocomposites > bare CeO2 NPs. A photocatalytic ability of 100 % for Hg(II) reduction was achieved within 40 min utilizing 1.5 % PdO/CeO2 nanocomposites, which was 2.2 folds greater than that of bare CeO2 NPs. The rate constant of 1.5 % PdO/CeO2 nanocomposite (0.106 min−1) is more 9.9 times than that CeO2 NPs (0.0107 min−1). The enhancement photocatalytic ability of PdO/CeO2 can be interpreted to the wide surface area, narrow bandgap, numerous active sites, fast mobility, efficient diffusion of Hg(II), and the high separation rate of photocarriers. Considering the promotion photocatalytic ability of heterojunction PdO/CeO2 nanocomposites, the heterostructure photocatalyst is of magnificent importance to the photocatalytic redox reactions and exhibits a significant effect on our human health and ecological environment.

Coupling Cu Coordination Polymers with CdS Forming an S-Scheme Heterojunction for Rapid Charge Separation and High Photocatalytic Activity.

Energy and the environment are significant impacting factors for the future development of humankind. In order to improve the corrosion resistance of CdS and decrease the recombination of photogenerated carriers, a novel Cu-CPs@CdS heterojunction with high efficiency mesopores was constructed by a simple hydrothermal method. The effective interfacial contact formation between nano-CdS and Cu-CPs promotes the transfer of photogenerated carriers while exhibiting a high spatial separation rate of charges. The photocatalytic performance of the heterojunction was evaluated by the photocatalytic degradation of organic pollutants and photocatalytic hydrogen generation. The photocatalytic degradation of ciprofloxacin (CIP) could reach 90.34%, and the hydrogen generation was high as 9227.82 μmol·g-1 under simulated sunlight irradiation. The boosted photocatalytic activity of Cu-CPs@CdS results from (i) the formation of coordination bonds, which not only enhanced the stability of heterojunctions but also provided a path for photogenerated carrier migration, (ii) integrating Cu-CPs, which provided more active sites, and (iii) the matched energy band structure between CdS and Cu-CPs that promoted speedy S-scheme interfacial charge-transfer pathways, culminating in efficient photogenerated charge separation and transfer. This research offered a fresh tactic to restrict photocorrosion and enhance the production of photocatalytic H2 over CdS-based catalysts.

Superior End-Group Stacking Promotes Simultaneous Multiple Charge-Transfer Mechanisms in Organic Solar Cells with an All-Fused-Ring Nonfullerene Acceptor.

The all-fused-ring acceptor (AFRA) is a success for nonfullerene materials and has attracted considerable attention as its high optical and chemical stability expected to reduce energy loss, and power conversion efficiency (PCE) approaching 15% in constructed all-small-molecule organic solar cells (OSCs). Herein, the intrinsic role of the structure of AFRA F13 and the reason for its high PCE were revealed by comparison with those of typical fused acceptors IDT-IC and Y6. An increased degree of conjugation in F13 leads to broader and red-shifted absorption peaks, facilitating enhancement of the short-circuit current. Multiple charge-transfer mechanisms are mainly attributed to the higher Frenkel exciton (FE) state due to the multiple transition ways for acceptors in the C1-CN:F13 system. The increased number of atoms contributing to the charge-transfer (CT) state facilitated the existence of more superior stacking patterns with easy formation of CT and FE/CT states and a high charge separation rate. It was found using the AFRA is an effective strategy to enhance end-group stacking, enhancing the borrowing of oscillator strength to promote multiple CT mechanisms in the complexes, explaining the high performance of this OSC device. This work is promising to guide designing an efficient AFRA in the future.

An S‐Scheme AgIn5S8/Bi2MoO6 Heterojunction for the Photocatalytic Degradation of Hydrochloride Tetracycline

AbstractOver the past few decades, the overuse of antibiotics has raised concerns about drinking water and potential health risks, especially the hydrochloride tetracycline (TC‐HCl). Therefore, it is crucial to develop a simple, low‐cost and high‐efficiency photocatalyst for the degradation of the pollutant. A novel photocatalyst with an S‐scheme heterojunction structure of AgIn5S8 and Bi2MoO6 was synthesized by using a solvothermal method. The heterojunction photocatalyst obtained demonstrates superior photocatalytic degradation activity for hydrochloride tetracycline (TC‐HCl) under visible light irradiation. It exhibits higher photocatalytic degradation performance than pure AgIn5S8 and Bi2MoO6 under the same conditions. The heterojunction with 3 % AgIn5S8 exhibited the highest degradation efficiency of 63.65 % within 40 minutes. Furthermore, the degradation rate is 6.21 times higher than that of AgIn5S8 and 2.18 times higher than that of Bi2MoO6. The improved photocatalytic activity is primarily attributed to the enhanced light absorption and the high rate of carrier separation resulting from S‐scheme heterojunctions.

Boosting intimate contact and charge transfer between carotenoid dye and Ti3C2Tx MXene for photocatalytic hydrogen production

Developing efficient heterojunction photocatalysts with improved light-harvesting capacity and high charge carrier separation rates for photocatalytic hydrogen production remains a challenge in the field of energy conversion. In this study, we synthesized two-dimensional Ti3C2Tx nanosheets through HF etching of Ti3AlC2 and combined them with carotenoid dyes (Car) with different structural characteristics using a solvent spontaneous volatilization method to construct novel Car@Ti3C2Tx Schottky heterojunctions. The intimate interface contacts between the two-dimensional Ti3C2Tx MXene and Car enhanced the light-harvesting capacity of the photocatalysts and promoted charge separation rates. The optimal sample, Car-3@Ti3C2Tx nanocomposite, exhibited excellent photocatalytic activity of 84.4 µmol h−1 g−1 for H2 production under visible light illumination. This work demonstrates the potential of earth-abundant organic Car dyes in constructing high-efficiency and low-cost photocatalysts for hydrogen production.

Enhanced photocatalytic degradation of organic pollutants in actual sewage water with a full-spectrum-responsive NaYF4:Yb,Tm@NaYF4:Yb,Nd@TiO2@g-C3N4 nanoheterojunction photocatalyst

Full spectrum-excitation photocatalysis is promising for the environmentally friendly treatment of actual sewage with sunlight. High-efficiency, stable NaYF4:Yb,Tm@NaYF4:Yb,Nd@TiO2@g-C3N4 (UPTC) nanoheterojunction photocatalysts were fabricated via facile chemical synthesis. Nanophotocatalyst characterization revealed good crystallinity, strong composite formation, and a high separation rate of photoexcited charges. The synthesized UPTC was excited by ultraviolet, visible light and infrared light, exhibiting excellent full spectrum-response. Under near-infrared irradiation at 808 nm and 980 nm, UPTC effectively degraded rhodamine B (RhB). Under simulated sunlight, UPTC decomposed 88.6% malachite green, 92.2% rose bengal, and 90.8% RhB in 90 min. In photocatalysis, ·O2- played a dominant role. Moreover, the nanoheterojunction structure greatly improved photoexcited carrier separation. UPTC nanoheterojunction had excellent recycling capability. In actual sewage treatment, UPTC degraded 36.5% ammonia-nitrogen under simulated sunlight. In addition, UPTC exhibited sufficient biosafety. This study offers a fresh potential approach for producing highly efficient, stable, and biosafe nanoheterojunction photocatalysts for sewage treatment.

Investigation of the Photocatalytic Performance, Mechanism, and Degradation Pathways of Rhodamine B with Bi2O3 Microrods under Visible-Light Irradiation.

In the present work, the photodegradation of Rhodamine B with different pH values by using Bi2O3 microrods under visible-light irradiation was studied in terms of the dye degradation efficiency, active species, degradation mechanism, and degradation pathway. X-ray diffractometry, polarized optical microscopy, scanning electron microscopy, fluorescence spectrophotometry, diffuse reflectance spectra, Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, UV-visible spectrophotometry, total organic carbon, and liquid chromatography-mass spectroscopy analysis techniques were used to analyze the crystal structure, morphology, surface structures, band gap values, catalytic performance, and mechanistic pathway. The photoluminescence spectra and diffuse reflectance spectrum (the band gap values of the Bi2O3 microrods are 2.79 eV) reveals that the absorption spectrum extended to the visible region, which resulted in a high separation and low recombination rate of electron-hole pairs. The photodegradation results of Bi2O3 clearly indicated that Rhodamine B dye had removal efficiencies of about 97.2%, 90.6%, and 50.2% within 120 min at the pH values of 3.0, 5.0, and 7.0, respectively. In addition, the mineralization of RhB was evaluated by measuring the effect of Bi2O3 on chemical oxygen demand and total organic carbon at the pH value of 3.0. At the same time, quenching experiments were carried out to understand the core reaction species involved in the photodegradation of Rhodamine B solution at different pH values. The results of X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and X-ray diffractometer analysis of pre- and post-Bi2O3 degradation showed that BiOCl was formed on the surface of Bi2O3, and a BiOCl/Bi2O3 heterojunction was formed after acid photocatalytic degradation. Furthermore, the catalytic degradation of active substances and the possible mechanism of the photocatalytic degradation of Rhodamine B over Bi2O3 at different pH values were analyzed based on the results of X-ray diffractometry, radical capture, Fourier-transform infrared spectroscopy, total organic carbon analysis, and X-ray photoelectron spectroscopy. The degradation intermediates of Rhodamine B with the Bi2O3 photocatalyst in visible light were also identified with the assistance of liquid chromatography-mass spectroscopy.

Bi/BSO Heterojunctions via Vacancy Engineering for Efficient Photocatalytic Nitrogen Fixation

AbstractPhotocatalytic nitrogen reduction represents a viable technology for green ammonia synthesis under mild conditions. However, the performance of the photocatalysts is typically limited by high charge carrier recombination and low adsorption and activation of nitrogen molecules. Herein, Bi/Bi2Sn2O7 (Bi/BSO) heterojunction nanocomposites are prepared via a one‐step hydrothermal method, where NaOH etching of oxygen vacancies in the Bi─O bonds of Bi2Sn2O7 (BSO) is exploited for the in situ formation of metallic Bi and hence Schottky junctions with the semiconducting BSO. This leads to a high separation rate of photogenerated charge carriers. Consequently, compared to the pure‐phase BSO, the Bi/BSO heterostructures exhibit markedly enhanced ammonia production, reaching an optimum rate of 284.5 µmol g−1 h−1, where the rectifying contact between the semiconducting BSO and metallic Bi facilitates directional BSO to Bi electron transfer, leading to enrichment of photogenerated electrons at the active sites of metallic Bi. First‐principles calculations confirm the alteration of active sites and the guided electron flow by the Schottky junctions and surface oxygen vacancies. Results from this study offer an effective paradigm of structural engineering in manipulating the photocatalytic activity of bismuth‐based pyrochlore materials toward nitrogen fixation to ammonia.

Molecular epidemiology, genetic diversity, antibiotic resistance and pathogenicity of Stenotrophomonas maltophilia complex from bacteremia patients in a tertiary hospital in China for nine years.

The Stenotrophomonas maltophilia complex (Smc) has emerged as a significant nosocomial pathogen contributing to increased mortality rates, particularly in case of bloodstream infections. This study employed whole-genome sequencing (WGS) to assess the genetic diversity, antimicrobial resistance profiles, molecular epidemiology and frequencies of virulence genes among 55 S. maltophilia isolates obtained from bacteremic cases over a 9-year period. Based on the threshold of 95% average nucleotide identity (ANI) and 70% digital DNA-DNA hybridization (dDDH) for genospecies delineation, we classified 37 isolates into 6 known species, all belonging to the Smc. The remaining 18 isolates sequenced in this study were assigned to 6 new genomospecies. Among the 55 isolates, we identified 44 different sequence types (STs), comprising 22 known and 22 novel allele combinations. The resistance rate of Smc against trimethoprim-sulfamethoxazole (TMP/SMX) was found to be 3.6%, with the sul1 and class one integron integrase genes (intI) detected in these isolates. All Smc isolates were susceptible to minocycline. Furthermore, all Smc strains harbored the motA, pilU, smf-1 and Stmpr2 genes. Genomospecies 1 (100%, n = 9), Stenotrophomonas maltophilia (84.21%, n = 19) and Stenotrophomonas sepilia (71.43%, n = 7) demonstrated a higher percentage of the afaD gene, which was also associated with a higher separation rate. In addition to motA, pilU, smf-1, and Stmpr2 genes, all S. maltophilia strains (100%) contained entA, gspD, KatA, and stmPr1 genes, while all genomospecies 1 strains (100%) contained afaD, entA, gspD, and KatA genes. Our study highlights the genetic diversity among Smc isolates from patients with bacteremia, revealing 22 novel ST types, 58 new alleles and 6 new genomospecies. S. maltophilia and S. pavanii were found to carry more virulence factors, emphasizing the importance of accurate strain identification. Minocycline emerged as a promising alternative antibiotic for patients who were resistant to TMP/SMX.

Ti-MOF-derived Ti3+-TiOx/CdIn2S4 heterojunction with a hollow structure for enhanced photocatalytic activity under visible light

The removal of refractory organic contaminants in the environment is vital, but developing highly active catalysts with a simple synthesis process remains a challenge. Herein, NH2-MIL-125(Ti) (Ti-MOF) as a template, Ti3+-TiOx clusters of different quantities were embedded in the CdIn2S4 nanosheets to construct Ti3+-TiOx/CdIn2S4 (TiCIS) heterojunction by an in-situ self-assembly strategy, which had a hollow structure, strong visible light absorption, high separation rate of carriers, and more active sites. During the degradation experiment of Rhodamine B (RhB), TiCIS25 exhibited the best photocatalytic performance, and 98.0% of RhB was degraded within 60 min of visible irradiation. The intermediates in the RhB degradation and their ecotoxicity were analyzed, which revealed that RhB degradation was a detoxification process. The radical trapping experiments and electron spin resonance (ESR) tests indicated that e-, 1O2, and ·O2- are the main active species for RhB degradation. Moreover, a possible photocatalytic mechanism was proposed based on electrochemical tests. The photodegradation performance of the as-prepared TiCIS catalyst under different reaction parameters (authentic water matrices, initial pH, coexisting anions, organic matter concentration, actual sunlight, reaction temperature, and multiple pollutants) and circulating experiments, as well as the photo-reduction process CO2, reflected that TiCIS25 possessed excellent practicability, cyclic stability, and universal applicability. Above all, TiCIS25 exhibited great potential in photocatalytic processes, and the work provided a feasible strategy for designing high-performance photocatalysts.

Facile preparation of ZnO/TiO2 nanocomposite photocatalysts and study of their photocatalytic performance

Due to its strong photocatalytic activity, chemical stability, resistance to chemical and optical corrosion, and non-toxic qualities, TiO2 has received a lot of attention as a significant semiconductor material. One of the main areas of research in the field of photocatalysis has always been the system made of ZnO, another significant semiconductor, which has stronger physical and chemical characteristics and photocatalytic activity than TiO2 and ZnO alone.The performance of the photocatalysts can be optimized by adjusting the ratio of the components in the complexes. It was found that the catalytic activity of the particulate ZnO nano photocatalysts could be improved by trace TiO2 addition and high TiO2 concentration in the complex, with higher degradation efficiency for methyl orange under simulated solar illumination. The enhanced performance was attributed to the high photogenerated electron-hole separation rate caused by the increased surface oxygen vacancy defects and the enhanced interfacial charge transfer of the pluralistic heterojunction structure. In addition, there is a certain selectivity of ZnO and TiO2 for the photocatalytic degradation of methylene blue and methyl orange, which is related to the charged nature of the catalyst surface and the ionic nature of the pollutant molecules. The inhibitor studies revealed that the degradation reactions of methylene blue and methyl orange involved the active species hydroxyl radicals, superoxide radicals, and photogenerated holes formed on the catalyst surface, with superoxide radicals dominating the methyl orange reaction. The produced photocatalysts' great stability was validated by cycling experiments. Further research on the impact of catalyst dosage and pH of the contaminant solution on the photocatalytic performance of the catalysts revealed that an increase in catalyst dosage resulted in a greater number of active sites for contaminant molecules and incident light, which increased the efficiency of contaminant degradation. In an alkaline environment, the efficiency of the catalyst for photodegradation of pollutants was significantly increased due to the high concentration of strongly oxidizing hydroxyl radicals contained in the alkaline solution.

Reexamining the effects of speed-accuracy instructions with a diffusion-model-based analysis.

There has been considerable interest in what components of decision-making change when speed or accuracy is stressed. In many early studies, quite strict assumptions were made about parameter invariance across experimental conditions (sometimes called selective influence). Here we fit the standard diffusion model to the data from four large experiments with speed-accuracy instructions (with over a million total responses), allowing all model parameters to vary freely between the speed and accuracy conditions. Results show that most of the observed differences between speed and accuracy conditions appear in the boundary separation parameter, followed by nondecision time, with small effects on drift rates. However, changes in drift rates are accompanied by changes in across-trial variability in drift rate, which cancels out the effect of drift rate on accuracy and response time. Another analysis in which across-trial variance in drift rate was kept the same in fits to speed and accuracy conditions produced no difference in drift rates. Generally, if speed is stressed moderately, then both boundary separation and nondecision time are reduced and any changes in drift rate are compensated for by changes in the across-trial variance in drift rates. If speed is stressed to a high degree (Starns et al., 2012), boundary separation, nondecision time, and drift rates are reduced. This is because (we hypothesize) encoding is restricted leading to a lower degree of perceptual information or match with memory. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Novel mesoporous Pt@n-AgI/n-α-MoO3 ternary nanocomposite for enhanced hydrogen production from glycerol under visible illumination

A novel mesoporous n-AgI/n-α-MoO3 nanocomposites with large surface area were constructed by hydrothermal approach utilizing hexamethylenetetramine (HMT) as an organic building block (cage-like). Pt nanoparticles (NPs) were highly distributed over AgI/α-MoO3 nanocomposites in situ during the photocatalysis reaction for photocatalytic H2 evolution under visible exposure. The H2 evolution results indicated that 9%AgI/α-MoO3 nanocomposite exhibited the best H2 evolution ability, and the total H2 amount was determined at about 24100 μmolg−1 within 9 h illumination using 1 g/L the photocatalyst dosage, which increased to 28920 μmolg−1 at 2.5 g/L. The H2 amount of AgI/α-MoO3 photocatalyst was fostered ∼40 and 10 times larger than that of α-MoO3 and AgI NPs. The optimal 9%AgI/α-MoO3 (2521.8 μmolg−1h−1) presented 34.4 and 8.61 times higher H2 evolution rate compared to α-MoO3 (73.23 μmolg−1h−1) AgI (292.91μmolg−1h−1). The resultant S-scheme AgI/α-MoO3 heterojunctions enhanced the separation efficiency of photocarriers with a remarkable enhancement of H2 evolution. The n-n heterojunction AgI/α-MoO3 nanocomposite inhibited the recombination of electrons and holes, decreased photoluminescence intensity, enhanced the current density, and promoted photocatalytic ability. The obtained AgI/α-MoO3 nanocomposite can maintain stability for 45 h of illumination continuously in the photocatalysis reactions for five consecutive cycles. These results provide a simple approach to designing S-scheme photocatalysts with a high separation rate of carriers to promote solar energy conversion efficiency.

Spatial charge separated two-dimensional/two-dimensional Cu-In2S3/CdS heterojunction for boosting photocatalytic hydrogen production

Two-dimensional (2D) beta indium sulfide (β-In2S3) shows great potential in photocatalytic hydrogen production due to its broad-spectrum response, relatively negative conduction band edge, high carrier mobility and low toxicity. However, the high charge recombination rate limits the application of In2S3. Here, we in-situ grew 2D cadmium sulfide (CdS) on the surface of In2S3 doped with copper ions (Cu2+) to construct a heterojunction photocatalyst that suppresses charge recombination. The in-situ grown method and shared sulfur composition were conducive to forming the efficient interface contact between In2S3 and CdS, promoting charge transfer and showing the high spatial charge separation rate, resulting in a hydrogen production rate of 868 µmol g-1h−1. The induced Cu2+ extended the light absorption range and stabilized the photocatalyst. By creating stable 2D/2D heterojunction photocatalysts with high charge separation efficiency, this work opens new possibilities for applying In2S3 materials in photocatalytic hydrogen production.

Family Stressors Experienced by Adolescents in Secondary Schools in Nairobi City County

Purpose: The aim of this study was to determine the different sorts of family stressors among adolescents in secondary schools in Nairobi County have observed.
 Methodology: The study employed a parallel convergent mixed-method design with a target population of 38,641 adolescents in Nairobi County secondary schools. Quantitative Data was collected from 398 adolescents in forms 2 and 3 via simple random sampling. All school categories were represented through cling cluster sampling, while simple random sampling selected respondents within each school. Qualitative data was purposively obtained from 10 students, 10 parents, and 10 teachers. Proven psychometric tools like Assessment of identity Development in Adolescence, Strengths and Difficulties Questionnaire, Children’s Perception of Inter-Parental Conflict Scale, and Dhaka Stress Scale-Adolescent collected quantitative data. Pearson coefficient correlations were calculated using Statistical Package for Social Sciences (SPSS version 25) to explore relationships between variables.
 Findings: The study established the types of family stressors and confined itself to parental conflict and family changes. The findings of the study revealed that a slight majority of secondary students experienced less intense parental conflict. However, the study results also showed slight high rate of separation, followed by extramarital affairs and divorce among the families’ stressors. Additionally, the qualitative data analysis showed that parental conflict, separation, and divorce were among the few family stressors unanimously reported by all three respondent groups (parents, teachers and students). Furthermore, both the students and parents reported domestic violence as one of family stressors.
 Unique Contribution to Theory, Practice and Policy: The study was anchored on Family Systems Theory. The study recommended the involvement of a counsellor, a chaplain and the government. There should also be a wide spread training of parents and the wider community. These interventions should be implemented not only within schools but also within communities. Therefore, parents, teachers, Non-governmental Organizations, churches, the government and stakeholders in psychological counselling must collaborate and implement interventions. This can create a more robust and holistic support system by adopting a comprehensive approach encompassing educational institutions and community settings.

Flexible, recoverable, and efficient photocatalysts: MoS2/TiO2 heterojunctions grown on amorphous carbon-coated carbon textiles

Most traditional powder photocatalysts are not easily recovered. Herein, we report a flexible and recoverable photocatalyst with superior photocatalytic activity, in which MoS2/TiO2 heterojunctions are grown on amorphous carbon-coated carbon textiles (CT@C-MoS2/TiO2). Recoverable CT@C-MoS2/TiO2 textile was used to degrade 10 mg L–1 rhodamine B, leading to a degradation rate of up to 98.8 % within 30 min. Such a degradation rate is much higher than that of most of the reported studies. A density functional theory (DFT) calculation results illustrate charge transfer mechanism inside TiO2-C, MoS2-C, and MoS2/TiO2 heterojunctions, which shows that CT@C-MoS2/TiO2 textile with three electron separation channels has a high photogenerated carrier separation rate, which remarkably enhances the photocatalytic activity. Our work provides a novel strategy to design an efficient and recoverable photocatalyst with high activity.

Seafarer market structure analysis of Korean merchant shipping in COVID-19

COVID-19 pandemic clearly demonstrates that seafarers are essential for sustaining world shipping services and global supply chain. Understanding the characteristics of supply and demand in seafarer market will be a solution for the bottleneck issues of seafarer change and shipping services. This paper explores the supply and demand of seafarer market in Korea and evaluates the effects of COVID-19 on both supply and demand sides of Korean seafarers by adopting regression models with panel data for the supply and time series data for the demand. First, this paper finds that the effects of COVID-19 are negative in the demand of Korean seafarer market even with the wider increase of tonnage of the Korean flagged ships in 2020. The demand shock seems to be resulted by the traveling restriction and stricter immigration measures to travellers after the announcement of COVID-19 pandemic. Second, supply in the regression models of panel data is affected negatively after declaration of the COVID-19 pandemic in 2020. The COVID-19 pandemic may trigger the hesitation of seafaring due to the travelling restriction and bottlenecks from seafarer changes onboard. Besides these findings, the correlation coefficients between the number of Korean seafarers of merchant ships and merchant fleet illustrate a diverse relationship between the two. The expansion of Korean ocean-going fleet is accompanied by the decrease of Korean seafarers on the Korean flag. The employment of foreign seafarers since 1992 has resulted in the continual decrease of ratings employment in the Korean flagged ships. The inflow of foreign deck officers in the Korean flagged ships after 2005 could lessen the officer deficiency caused by high separation rate of Korean deck officers. This inflow implies that seafarer market in a country not only affects global seafarer market in the world through the changes of seafarer supply and demand in the country, but is affected by the global market. The dual markets of Korean seafarers in ocean-going and coastal shipping present the following phenomena: severe aging of seafarers in coastal shipping and wider difference in welfare level of seafarers between the two. Further research on wage and career advancement of Korean seafarers would widen and deepen our understanding on seafarer market both for Korea and the rest of the world.

A Systematic Review on Lithium-Ion Battery Disassembly Processes for Efficient Recycling

Recycling plays a crucial role in achieving a sustainable production chain for lithium-ion batteries (LIBs), as it reduces the demand for primary mineral resources and mitigates environmental pollution caused by improper disposal. Disassembly of the LIBs is typically the preliminary step preceding chemical recovery operations, facilitating early separation of components consisting of different materials. Despite that extensive research has been conducted on the chemical processes involved in the recycling of LIBs, systematic studies on disassembly processes in the recycling process are relatively scarce. In this research, a systematic review was conducted on the publications from major databases, such as Scopus, SpringerLink, and others, to explore the current state of disassembly processes in LIBs’ recycling. The results emphasize disassembly as a crucial process for achieving a high material separation rate and ensuring a high degree of purity of the recycled active material. Moreover, automated disassembly can significantly raise productivity and reduce disassembly costs. Thus, it improves disassembly efficiency and increases economic as well as environmental benefits. Most researchers have focused on disassembly at the pack or module level. Investigation into extending the disassembly depth from cell to individual components is limited, particularly in automated approaches. Therefore, further research is highly recommended to explore the feasibility and potential of novel automated disassembly procedures at the cell level. This can contribute to improving the efficiency and sustainability of the recycling process for LIBs.