Search

A comprehensive educational framework is provided by the Conceive-Design-Implement-Operate (CDIO) which is particularly relevant to engineering and applied sciences. This paper investigates the application of the CDIO approach in the field of chemistry pedagogy in Vietnam focusing on its adaptability to the current educational demands and its potential to enhance the competency of future teachers. The CDIO approach develops training curricula and outputstandards based on input from teachers,students, alumni and recruitment firms. This study uses the CDIO approach extensively with professional knowledge, social awareness and creative tendencies. The study involved a survey of 240 chemistry teachers and 242 students from various universities across Vietnam. Data were collected through online surveys using Google Forms and processed using SPSS software for statistical analysis. The research analyzed the alignment of practical teaching activities with CDIO standards and developed a framework for experimental practice competency. Findings indicated a robust implementation of the CDIO approach in chemistry pedagogy. In laboratory safety, experimental planning, execution and competence were high. The study shows that the CDIO strategy enhances professional competence and practical abilities in Vietnamese chemistry pedagogy students. It promotes collaboration and personal growth to meet changing educational needs. The CDIO approach could transform chemistry pedagogy in Vietnam suggesting science education reforms and capacity building.

Studies investigating chemistry students' understanding of intermolecular forces have listed alternative conceptions; however, there is a call to investigate why students might have these alternative conceptions. This study describes how second semester general chemistry students predict the location of dipole-dipole forces between two molecules from a resource activation perspective. During interviews, 18 students were asked to describe the location of forces between four pairs of molecules. Students relied on one or more of the following approaches in determining location: (1) attraction between opposite charges, (2) electronegativity differences, (3) biggest electronegativity values, (4) largest atomic size, and (5) molecular shape. Each student's approach is characterized by the resources being activated and, in particular, students' use of electronegativity. Students' use of electronegativity varied, including comparing electronegativity values between unbonded atoms within a molecule and between atoms present on different molecules. The findings suggest future research directions and teaching implications that could improve students' understanding of intermolecular forces including the explicit integration and assessment of the concepts of electronegativity and intermolecular forces.

Retention and underrepresentation of diverse ethnic groups have been and continue to be problematic in the science, technology, engineering, and mathematics (STEM) disciplines in the United States. One foundational course that is required for all STEM majors is general chemistry. One way to increase retention and diversity in STEM majors is by targeting students' social-psychological beliefs about their academic success through the implementation of social-psychological interventions. These short impactful exercises aim to change students' thoughts, feelings, and beliefs about their academic success and affective characteristics. In this exploratory study, we designed and implemented two chemistry specific growth-mindset modules (GMMs) in two first-year chemistry courses (general chemistry 1 (GC1) and general chemistry 2 (GC2)) at a Hispanic-Serving Institution (HSI). Students worked on the GMMs asynchronously at two specific time points throughout the semester. Using a mixed-methods approach, we assessed students': (1) changes in mindset beliefs, chemistry self-efficacy (CSE), and chemistry performance, (2) perceptions towards failures and challenges, and (3) perceptions on growth-mindset modules (GMM) after participation in GMMs. Overall, GC2 students shifted towards a growth mindset and away from a fixed mindset, with small to medium effect sizes detected. No statistically significant changes in GC1 students' mindsets were detected throughout the study period. For both courses, students increased in CSE by the end of semester. Furthermore, GC1 students who participated in any portion of the GMM intervention achieved higher scores on the ACS exam compared to those who didn't participate. Additionally, students' written responses highlighted an improved attitudinal change towards failures and challenges after participating in GMMs. For both courses, over 95% of the students agreed that the GMMs were valuable, over 95% students indicated they developed more positive attitudes and perspectives towards challenges, and over 96% students believed they could learn challenging topics with effort, determination, and persistence. While these results show differences in performance, CSE, mindset scores, and attitudinal change after participation in GMMs, it is also important to acknowledge that self-selection into the study may be one of the factors for explaining such differences. Results and implications for practice are discussed.

The aroma volatile compounds in tomatoes are strongly linked to taste and flavor. Commercial tomato varieties, however, generally lack flavor. Tomato breeding programs have therefore started to focus on increasing the flavor-enhancing volatiles, which can be more easily altered than the sugar content. Analytical efforts that identify key flavor volatiles are therefore an important part of tomato improvement programs. Based on this real-world goal, an upper-level undergraduate analytical laboratory exercise has been developed that utilizes solid-phase microextraction (SPME) and gas chromatography-mass spectrometry to characterize tomato volatiles. Students adsorb volatile organic compounds (VOCs) and a spiked internal standard onto SPME fibers, and these volatiles are thermally desorbed in a gas chromatograph--mass spectrometer (GC-MS) for identification and quantification. VOCs from hybrid heirloom tomatoes (open-pollinated, older cultivars not bred for industrial agriculture) and store-bought tomatoes are compared and normalized to the internal standard, and students determine which volatiles contribute to positive (and negative) taste perceptions. The laboratory exercise has been employed successfully in our Instrumental Analysis course over three years. Using previously obtained data, the exercise was also modified for remote (Zoom) laboratory learning. The experimental protocol is robust with few technical issues, and students produce replicable data. Because students can relate easily to the subject matter of the research, engagement is high. A large, complex data set is produced in this exercise, and students learn to draw conclusions from this data set that mimic real-world, authentic research.

The initial period of young teachers' careers is always significant in developing their professional capability. This is when teachers start coming into contact with practical teaching, which is more diversified than the theoretical training at the University. In this research, the authors propose a process of combining the Lesson Study model with the micro-lesson teaching method. This process helps young teachers, especially those working in the Northern of Vietnam, improve their planning and implementation of a lesson plan following the Lesson Study model. It has four steps: (1) plan a Lesson Study; (2) organize demo teaching and attend lessons; (3) self-evaluate and discuss lessons; and (4) apply for practical teaching. The methodology research is carried out on 62 young teachers in Vietnam to measure the pre-impact and post-impact results. The results reveal that the researched group has made significant progress on their teaching performances (the average points for their capability of planning lessons have increased from 2.54 to 3.28 and the average points for their capability of implementing lesson plans have increased from 2.48 to 3.18). This development can be considered as an excellent experience to bring the Lesson Study model into Vietnamese schools to improve teaching sustainably.

A new teaching assistant model was adopted and qualitatively assessed for the general chemistry laboratory, in which both an undergraduate and a graduate teaching assistant provided instruction to students during the lab. Verbal interactions between graduate and undergraduate teaching assistants were recorded, transcribed, and coded using the modified Laboratory Observation Protocol for Undergraduate STEM (LOPUS). The codes were applied to capture how discussions, questioning, and explanations were conducted. In addition, the content discussed was coded to identify specific areas that pose challenges for students. Sizable differences were not observed between the number of interactions of the initiation, explanation, and questioning codes between graduate and undergraduate teaching assistants. Of the interactions, 77% focused on questions and discussions regarding the experimental setup. Discussions on the implications with regards to the effective use of undergraduate and graduate teaching assistants in chemistry laboratories are included.

This paper describes the creation of a theme-based first quarter, of a two quarter sequence, general chemistry laboratory course following an argument driven inquiry format and employing specifications grading. The course contains four, two-week projects investigating the chemistry of a popular sports drink. The sugar content, dye concentration, buffering capacity, and the kinetics of dye decomposition are investigated for various flavors of Gatorade. Specifications grading is used to foster teamwork and to provide an opportunity for revision and resubmission of student work. A modified LCAS survey measured student perception of course content.

At-home chemistry experiments are increasingly important to enable high-quality online and hybrid instruction. These class modalities provide significant challenges and also dramatically expand the accessibility of education to those who work or care for family during traditional school hours or have significant commutes to campus. This work demonstrates a novel approach to quantifying citric acid in lemon juice using baking soda as a titrant that requires no specialized equipment. Despite being a weak acid/weak base titration, the gas evolution of carbon dioxide brings this reaction to near completion. Since this process can be relatively slow, the candy Mentos is used to drive rapid gas evolution. The cessation of this vigorous gas evolution is used to track the end point of the titration. The results of this at-home titration were compared to a traditional in-person titration of citric acid in lemon juice (using sodium hydroxide as the titrant and a phenolphthalein indicator) performed by the same students. The at-home titration and the in-person titration yielded citric acid concentrations in lemon juice of 0.20 M (±0.08 M) and 0.25 M (±0.03 M), respectively.

According to General Statistics Office of Vietnam on 30th September, 2017, Vietnam has 858,800 teachers, and among those, 615,720 people were female (occupied 71.7%). It can be seen that female teachers made up a big percentage in the education sector. Besides, STEM education is soaring as a new approach in training with prominent advantages, such as: theories embedded in actual practices, ability-oriented development, pressure reduction in studying… This is not only a trend but also a necessary element in new teaching modules at high school -- which will be implemented in academic year 2020-2021 in Vietnam. As a result, it is necessary to consider the gender factor in the process of training and developing teaching with STEM education. This paper will present the results from the research that took place from 2015 to 2018 within Thai Nguyen University of Education.

Emphasizing stoichiometry appears to be a norm of introductory chemistry courses. In this longitudinal and mixed-methods study, we examined how the emphasis on stoichiometry in assessments of introductory chemistry impacted educational equity and student learning. Using quantitative methods, we identified mole and stoichiometric conversions as two of the most frequently assessed and inequitable competencies, perpetuating systemic inequities in access to pre-college mathematics preparation. Above all other competencies, midterm assessments of stoichiometry were the most impactful as the strongest predictor of students' scores on both the first and second-semester introductory chemistry final exam. These results informed the development of a think-aloud protocol used to describe how students approached assessments of stoichiometry. Students described stoichiometry as a step-by-step series of calculations, rarely associating this algorithm with the process of a chemical reaction by which reactants break bonds and rearrange to form products. Student responses suggest stoichiometry substitutes learning how to apply chemistry to think about the problems scientists solve for memorizing algorithms to solve math problems in the context of chemistry. Shifting the foundation of introductory chemistry courses from algorithmic to applied competencies reflects scientific practice and maybe one strategy for educators to disrupt systemic barriers to access and retention in STEM Education. Based on these findings and the advancements of other research, we offer implications for supporting educators as they iteratively develop increasingly relevant and equitable assessments of introductory chemistry.

To gauge the variability in expert problem-solving strategies for stoichiometry problems, a set of experts in different career tracks were studied with the cohort including 17 graduate students in chemistry, three college chemistry instructors, and seven college graduates working in the industry. The goal of the study was to determine whether variability would be observed based upon experience and career trajectories. The data were collected using interviews and analyzed qualitatively and quantitatively using the COSINE (Coding System for Investigating Sub-problems and Network) method. Although the method was developed for the analysis of undergraduate problem-solving, it appeared to be effective in examining experts' problem-solving in chemistry as well. The study revealed similar abilities for succeeding at solving a series of problems, but the strategies were variable for the three cohorts of experts. Specifically, the amount of information used to solve the problems differed across the three cohorts with graduate students focusing more upon each of the specific subproblems within each problem compared to industry chemists utilizing the big-picture approach in lieu of breaking down each problem into respective subproblems. Familiarity with the question types and ability to chunk information were common characteristics observed consistently for the expert participants, which is consistent with existing research.

Quantitative metrics are widely employed to determine the probability of an applicant succeeding in a specific program of interest, ranging from undergraduate or graduate admissions to fellowships. The admissions office at the United States Military Academy at West Point uses an internal college entrance examination rank (CEER) assessment algorithm of high school students, based on ACT and SAT scores in addition to consideration of high school performance, to assess student academic abilities and their probability of surpassing graduation requirements. To develop a tool for predicting student performance in first-semester general chemistry, we utilized CEER scores to predict student success on the national exam produced by the American Chemical Society (ACS) for general chemistry. Our results show that CEER is a strong predictor of student outcomes and a better predictor when compared to SAT Math, ACT Science, or ACT Math in isolation. Further stratification of the CEER distribution into four categories, ranging from at-risk to high achiever, identified a gradient by which students are likely to exceed the national average on the ACS exam. To further assess this prediction, we then demonstrated that the CEER brackets correlated closely to student grades in the course, therein illustrating its utility in predicting categories of students who are likely to fail, underperform, or excel. We anticipate that these tools are broadly generalizable to undergraduate admissions decisions, can assist in the placement process for students in general or advanced sections of chemistry, could yield insight when making scholarship or fellowship decisions, and more broadly can facilitate the design of group learning dynamics aimed at enhancing student outcomes.

The overall goal of our work is to disrupt pervasive narratives and misplaced assessments of what defines scientific brilliance, specifically in the introductory chemistry classroom. The traditional design of science, technology, education, and math (STEM) courses perpetuates the narrow view that intelligence is characterized by innate talent, knowing lots of information, and being quick and correct. This view disproportionately impacts students historically underserved in STEM. The Chem Avengers aim to transform chemistry education into an inclusive practice where all learners can thrive. The work reported here is focused on creating and implementing group-worthy tasks that support equitable participation. These tasks center around sorting, using, and making sense of data, trends, and patterns.

Our study describes student outcomes from an undergraduate chemistry course that implemented a flipped format: a pedagogical model that consists of students watching recorded video lectures outside of the classroom and engaging in problem solving activities during class. We investigated whether (1) interest, study skills, and attendance as measured by self report improved during the term as a result of course format (n = 252) and (2) students in a flipped chemistry course earned higher grades in the subsequent chemistry course compared with students who enrolled in the nonflipped course that same term (n = 295). Although we found no significant differences between students' self-reported interest and study skills at the end of the term, we found that students enrolled in the flipped course reported attending class more often than students in the non-flipped course (ß = 0.32). We also found that after controlling for student-level covariates related to achievement (such as SAT Math scores and grade in previous chemistry course), students enrolled in the flipped chemistry course experienced, on average, a statistically significant increase of half a standard deviation (ß = 0.55) in their grade in the subsequent chemistry course. We discuss implications for study of flipped instruction.

This article describes the educational and public engagement outcomes of an activity called the "ChemClout Challenge" that was implemented in a general chemistry course at UC Riverside. Students worked in groups to make chemistry-themed videos, posted them to social media platforms, then voted on their favorite videos. The majority of students elected to make videos where they anthropomorphized general chemistry concepts, physically acting out principles such as ideal gas law relationships and electrolyte solubility. Students reported enjoying these anthropomorphized videos most. These types of videos received over one million views worldwide within the first month of posting on the social media platform, TikTok. After the course was over, 75 students completed voluntary Likert scale surveys to assess the educational and outreach impact of the ChemClout Challenge. Eighty-eight percent of students reported that the activity made chemistry more relatable, whereas 76% of students noted that the activity helped them retain course concepts two months after the course was completed, indicating the activity benefitted student learning. Moreover, 84%of students reported that their friends and family members outside of UC Riverside watched the videos, with 72% of students reporting that they explained the chemical concepts of their videos to their friends. These studies indicate that student-created social media videos that anthropomorphize chemistry are highly effective vectors for student-centered learning and public engagement in chemical concepts. This activity may find particular utility for educators during the COVID-19 pandemic, as it is compatible with distance learning.

For some professionally, vocationally, or technically oriented careers, curricula delivered in higher education establishments may focus on teaching material related to a single discipline. By contrast, multidisciplinary, interdisciplinary, and transdisciplinary teaching(MITT) results in improved affective and cognitive learning and critical thinking, offering learners/students the opportunity to obtain a broad general knowledge base. Chemistry is a discipline that sits at the interface of science, technology, engineering, mathematics, and medicine(STEMM) subjects (and those aligned with or informed by STEMM subjects). This article discusses the significant potential of inclusion of chemistry in MITT activities in higher education and the real-world importance in personal, organizational, national, and global contexts. It outlines the development and implementation challenges attributed to legacy higher education infrastructures (that call for creative visionary leadership with strong and supportive management and administrative functions), and curriculum design that ensures inclusivity and collaboration and is pitched and balanced appropriately. It concludes with future possibilities, notably highlighting that chemistry, as a discipline, underpins industries that have multibillion dollar turnovers and employ millions of people across the world.

The emergence of the novel coronavirus disease-19 (COVID-19) required a rapid shift from in-person instruction to remote learning in our second-semester general chemistry course at the United States Military Academy (USMA), a predominantly undergraduate institution that takes pride in faculty accessibility to students. The decision to conduct remote instruction took effect when students were on spring break; consequently, most students had limited academic resources in hand. This represented a significant paradigm shift for both USMA faculty and students since the institution places an emphasis on in-person engagements with students, as reflected by our low student-to-faculty ratio. We adapted our usual in-person, student-driven instructional method to the remote environment within a 7 day period, which impacted 174 students and six faculty course-wide who were new to the technology, resources, and methodology associated with remote instruction and learning. This communication discusses lessons learned from the transition to asynchronous remote teaching, with a critical focus on the advantages and disadvantages of the adopted teaching methodologies, and includes a discussion of course design and the corresponding adaptions to this new pedagogical environment. We anticipate that these accounts can be leveraged by the broader chemical sciences community to better inform the planning and execution of instruction in future academic terms under remote, in-person, or hybrid (partially remote and partially in-person) environments.

Online homework systems have been shown to help student achievement in chemistry courses. This study sought to compare the levels of knowledge retention in students over the course of a semester, using two different types of homework systems--the adaptive-responsive system and the traditional-responsive system. Two sections of a first semester general chemistry course were investigated, with one section using the adaptive-responsive system and the other using the traditional-responsive system. Students' grades on cumulative exams were compared across both sections, and it was found that students using the adaptive-responsive system scored significantly higher on the exams and retained significantly more information than the students in the other section. The results of this study should help inform the choices educators make regarding the homework system they choose to use, or even which parts of the different systems they choose to use or not to use based on the outcomes they would like for their student population.

When campuses across the world needed to transition to the online format due to the COVID-19 pandemic, there were many challenges educators faced, and addressing academic integrity issues were some of the most important. Certain strategies, such as online proctoring or additional software, were not available to most institutions because the expenses and training were too much to overcome. A more pedagogical and cost-effective strategy involved modifying the assessment format in a way that minimized or discouraged cheating. This paper presents strategies that effectively minimize cheating while addressing learning outcomes.

The instruction of high enrollment general and organic chemistry laboratories at a large public university always has curricular, administrative, and logistical challenges. Herein, we describe how we met these challenges in the transition to remote teaching during the COVID-19 pandemic. We discuss the reasoning behind our approach, the utilization of our existing web-based course content, the additions and alterations to our curriculum, replacement of experimental work with videos, the results of both student and TA surveys, and lessons learned for iterations of these courses in the near future.

Tumor acidosis is one of the hallmarks indicating the initiation and progression of various cancers. Here, we present a protocol for preparing a hyperpolarized (HP) 13C-bicarbonate tissue pH MRI imaging contrast agent to detect aggressive tumors. We describe the steps for the formulation and polarization of a precursor molecule 13C-glycerol carbonate (13C-GLC), the post-dissolution reaction, and converting HP 13C-GLC to an injectable HP 13C-bicarbonate solution. We then detail procedures for MRI data acquisition to generate tumor pH maps for assessing tumor aggressiveness. For complete details on the use and execution of this protocol, please refer to Mu et al.1.

The Chemistry Science Investigation: Dognapping Workshop was designed to (i) target and inspire fourth grade students to view themselves as "Junior Scientists" before their career decisions are solidified; (ii) enable hands-on experience in fundamental scientific concepts; (iii) increase public interaction with science, technology, engineering, and mathematical personnel by providing face-to-face opportunities; (iv) give teachers a pathway forward for scientific resources; (v) meet the New Mexico K-5 Science Benchmark Performance Standards; (vi) most importantly, ensure everyone has fun! For this workshop, the students are told they will be going to see a Chemistry Magic Show, but the performance is stopped when the Chemistry Dog is reportedly stolen. The students first clear their names using a series of interactive stations and then apply a number of science experiments to solve the mystery. This report describes the workshop in detail, which is suitable for large (~100 students per day) audiences but has flexibility to be modified for much smaller groups. An identical survey was given three times (before, immediately after, and 2 months after the workshop) to determine the impact on the students' perception of science and scientists as well as determine the effectiveness in relaying scientific concepts through retention time. Survey responses indicate that scientific information pertaining to the workshop is retained for up to 2 months.

Purpose: This paper aims to discuss the methods that were used to do egalitarian research with ten Historically Black Colleges and Universities (HBCUs). Rather than doing research "on" these institutions, the authors worked with them to understand their successes and build upon their capacity in the science, technology, engineering and math (STEM) areas. Through this process, the authors aimed to bring exposure and interest to the practices that HBCUs use to increase and nurture success in African American students--practices that are rarely used in mainstream STEM programs and, in fact, run counter to well-established practices across STEM. The goal is to challenge traditional methods for pursuing STEM education research as the authors offer alternative methods the uplift and empower HBCUs. Design/methodology/approach: The authors used the constant comparative method in developing, testing, and writing-up the HBCU success stories. The constant comparative method collects data in a systematic way by engaging in ongoing exploration and verification of findings with key stakeholders (in this case, the teachers, students and staff at the HBCUs). Across the ten HBCUs in the sample, at least one success story or model at each institution was identified; in some instances, there were more. Findings: The research project had several implications for the social and economic health of society. First, supporting the work of HBCUs contributes to the diversification of the STEM fields and addresses the severe drought in the STEM workforce. It is without doubt that a diverse workforce--the unique perspectives and backgrounds of each individual--has a positive and significant influence on progress and innovation in any field. Despite increasingly growing minority communities across the country, many Blacks continue to face roadblocks that impede their opportunities and abilities in the K-20 pipeline and STEM education, specifically. Because HBCUs have a long history and record of tearing down those roadblocks and contributing Black students to the STEM workforce, they are prime and optimal sites for long-term investment. Second, improving the abilities of HBCUs to support student success in STEM also increases the likelihood of greater STEM minority teachers and faculty. A significant factor in the success of minority students in STEM is the opportunity to be taught and mentored by faculty members that look like them and/or deeply understand their personal background and struggles. For many Black students, the presence of a Black science professor can improve and retain student interest and aspiration in STEM. But with so few Black STEM faculty members, many students can easily fall through the cracks. Third, aside from the nation's security and health, supporting HBCUs' work in STEM student achievement represents immeasurable benefits for the individual and his/her family for many generations to come (i.e. society overall). Occupations in STEM are plentiful and fruitful for those who achieve the required credentials. Increasing opportunities for Black students to pursue these STEM careers can establish a path toward upward social mobility. The realization of these benefits is contingent upon the investment in early achievement in STEM courses. Research limitations/implications: Several research based outcomes are scheduled to result from this project, including a major policy report on HBCUs and their approaches to STEM education (co-constructed with the HBCU representatives); several peer reviewed articles (authored by us as well as the HBCU representatives); a national convening (showcasing both the best practices and the results of the HBCUs' funded capacity building projects with the HBCU representatives as the primary speakers rather than us); a website featuring the work of the 10 HBCUs, active use of social media to disseminate the findings of the project; several op-eds written for a general audience and co-authored with HBCU representatives; and an authored book published by a university press. Practical implications: Best practices gleaned from this project are being shared in a scholarly manner, but they will be shared in ways that are accessible to practitioners, including presidents, faculty, academic advisors, student success staff and other HBCU practitioners. In addition, best practices will be shared with majority colleges and universities to strengthen and improve practices more broadly in STEM. The authors are working with organizations such as the Association of American Universities, Association of Public Land Grant Universities and the American Association of Colleges and Universities to showcase the work of HBCUs and disseminate information. Social implications: Conducting research projects in which the research inquiry is co-constructed and the resulting research products are also co-constructed and even co-authored is an empowering and collaborative way to work across institutional types. More importantly, this approach brings attention to those researchers and teachers at HBCUs that are doing the day-to-day work with students, training them to be scientists, doctors and professors. Too often, only those conducting studies on STEM are credited with "discovering" success models for student learning. The authors think that those who have created these models and use them should be recognized and included in the research and dissemination process, and the authors encourage others to think more broadly and openly about collaborative research that engages the voices of HBCU researchers and students. Originality/value: This project also has much to teach others about collaborating through research. First, collaborating when conducting research related to STEM is essential, as it encourages collaboration within STEM and among STEM researchers. HBCU researchers that were a part of our project--biologists, physicist and chemists--were encouraged to work across disciplinary lines and together to understand their own STEM education practices more fully.

An update to the thermochromic cobalt(II) chloride equilibrium demonstration is described. Filter paper that has been saturated with aqueous cobalt(II) chloride is heated for seconds in a microwave oven, producing a color change. The resulting pink and blue map is used to colorfully demonstrate Le Châtelier's principle and to illuminate the hot spots in the microwave oven. The demonstration is a quick, easy, and colorful way to introduce Le Châtelier's principle to students in high school or general chemistry courses.

Here, a series of semi-interpenetrating polymer network (semi-IPN) hydrogels were synthesized and investigated hy combining three materials such as N-isopropylacrylamide (NIPAM), N,N'-diefhylacrylamide (DEA), and acrylic acid (AAc). The linear copolymer p(NIPAM-co-AAc) was introduced into DEA solution in the presence of N,N'-methylenebisacrylamide to synthesize p(NIPAM-co-AAc)/pDEA semi-IPN hydrogels using free radical polymerization. Scanning electron microscope images demonstrated the porous morphology of hydrogels with pore sizes in the range of 220-969 [micro]m. The physicochemical properties of polymers were evaluated by various characterization techniques, including gel permeation chromatography, dynamic light scattering, differential scanning calorimetry, rheological measurement, mechanical properties, and swelling behaviors. The results indicated that the introduction of linear copolymers into conventional hydrogels has significantly improved the properties of the hydrogels. Besides, the use of NIPAM has significantly improved the thermal sensitivity of the polymers in this work. Finally, a selected semi-IPN hydrogel was evaluated for its potential for the drug release of paracetamol. The sorption of paracetamol was an exothermic process that obeyed the Freundlich isotherms, with the highest sorption of 119.57 mg/g. The paracetamol release followed the Korsmeyer-Peppas model and was consistent with the Fickian diffusion mechanism. Key words: pH-thermoresponsive hydrogels, N-isopropylacrylamide, N,N'-diefhylacrylamide, acrylic acid, paracetamol, 1. Introduction A crosslinked hydrophilic polymer that is capable of absorbing water without dissolving is named hydrogel. Hydrogels sensitive to environmental stimuli such as temperature, pH, ionic strength, light, pressure, [...]

Here, a 1-octadecanol (OD)/methylated mesoporous silica (OD/M-MS) shape-stabilized phase-change material (SSPCM) was prepared with enhanced thermal energy storage. The M-MS was synthesized by methylation of low-cost MS with trimethylchlorosilane. Fourier-transformed infrared spectroscopy (FTIR), [N.sub.2] adsorption-desorption isotherm, and thermogravimetric analysis confirmed successful methylation ofMS. OD was then impregnated into the poresof MS and M-MS to form OD/MS and OD/M-MS SSPCMs, and their thermal properties were thoroughly characterized and compared. FTIR result of OD/MS revealed interfacial hydrogen bond (H-bond) interactions between the hydroxyl group (-OH) on the OD molecules and silanol groups (Si-OH) on the MS surface. These interactions prevented the free movement and ordered arrangement of OD molecules for crystallization, thus declining the heat storage capacity. By methylating the MS surface, the H-bond interactions were suppressed and the OD/M-MS could recover the thermal performance. The heat storage capacity increased by 96.8% from 43.5J [g.sup.-1] of OD/MS to 85.6J[g.sup.-1] of OD/M-MS. Moreover, a test of 400 accelerated thermal cycles proved good thermal reliability for OD/M-MS SSPCM. This work provides an effective strategy to achieve OD/M-MS SSPCM with low cost and high thermal performance, promising for large-scale thermal energy storage applications. Key words: 1-octadecanol, mesoporous silica, surface methylation, phase change material, thermal energy storage, 1. Introduction Due to the rapidly diminishing supply of natural energy resources, primarily fossil fuels, the development of novel energy techniques is urgently required to compensate for the energy demand. [...]

This 8-hour experiment (spread over two 4-hour sessions) is designed to equip students with essential skills in polymer synthesis, particularly in synthesizing polymers of well-defined molecular weight. The experiment involves the synthesis and characterization of poly(vinyl neodecanoate) via living free radical polymerization, specifically the reversible addition fragmentation chain transfer (RAFT) process. The commercial availability of the RAFT agent employed (ethylxanthogenacetic acid) enables an efficient laboratory practice without recourse to extensive synthetic chemistry. Through the current experiment, undergraduate students gain invaluable laboratory experience in one of the living free radical polymerization techniques that has revolutionized contemporary polymer science. (Contains 1 table, 4 figures and 5 notes.)

Gold nanoparticles (AuNPs) have found use in broad range of applications such as in catalysis and nanomedicine. Despite the fact that thiol-based AuNPs have been widely studied, they suffer from relative instability in various conditions, such as high and low temperatures, pH variations, and are prone to oxidation. Over the last decade, N-heterocyclic carbenes (NHCs) have been under spotlight as suitable ligands to stabilize metal nanoparticles and surfaces. Although NHC-functionalized AuNPs have been shown to outperform their thiol-based analogs in terms of stability, their applications in nanomedicine have not been realized. Hybrid nanomaterials, such as AuNPs tagged with [pi]-conjugated molecules with aggregation-induced emission (AIE) property, are promising candidates to develop fluorescent materials for cellular imaging. The combination of NHC-stabilized AuNPs with AIE to form stable, fluorescent hybrid AuNPs is of significant interest to open the door to develop new NHC-based nanomaterials. Herein, we report the synthesis and characterization of water-soluble fluorescent NHC-decorated AuNPs for potential applications in nanomedicine. Their stability in biologically relevant conditions is investigated. Key words: gold nanoparticles, N-heterocyclic carbene, tetraphenylethylene, fluorescent, Introduction Metal nanoparticles, and especially gold nanoparticles (AuNPs), have been at the center of most new technologies since their first discovery. Because of their nanomeric size and hence, their high [...]

Utilizing hot electrons generated from localized surface plasmon resonance is of widespread interest in the photocatalysis of metallic nanoparticles. However, hot holes, especially generated from interband transitions, have not been fully explored for photocatalysis yet. In this study, a photocatalyzed Suzuki-Miyaura reaction using mesoporous Pd nanoparticle photocatalyst served as a model to study the role of hot holes. Quantum yields of the photocatalysts increase under shorter wavelength excitations and correlate to "deeper" energy of the holes from the Fermi level. This work suggests that deeper holes in the d-band catalyze the oxidative addition of aryl halide R-X onto Pd0 at the nanoparticles' surface to form R-PdII-X complex, thus accelerating the rate-determining step of the catalytic cycle. The hot electrons do not play a decisive role. In the future, catalytic mechanisms induced by deep holes should deserve as much attention as the well-known hot electron transfer mechanism.

We have recently reported the synthesis and application of boron-nitrogen dihydroindeno[1,2-b]fluorene derivatives as acceptors in organic photovoltaic devices. Their modest observed efficiencies may be related to the properties of their reduced congeners. In this work, we report two new members of this family of compounds prepared via the electrophilic borylation of 2,5-di-p-tolylpyrazine followed by an arylation of the boron center with [ZnAr.sub.2] reagents. Two derivatives, 1 (Ar = 2,4,6-[F.sub.3][C.sub.6][H.sub.2]) and 2 (Ar = [C.sub.6][F.sub.5]) were synthesized, and their radical anions, [1*.sup.-] and [2*.sup.-], were formed via chemical reductions with [CoCp*.sub.2] and [CoCp.sub.2], respectively. Through comparison of structural parameters, as well as spectroscopic and computational data, the unpaired electron in the radical anions is localized in the planar core of the molecule, and dimerization is disfavored as a result. However, unlike the neutral starting materials, [1*.sup.-] and [2*.sup.-] are reactive toward ambient atmosphere. These observations suggest that the reduced compounds are stable toward intrinsic degradation pathways but subject to extrinsic degradation in device operation. Key words: radical anions, boron, heterocycles Nous avons récemment décrit la synthèse et l'application de dérivés de dihydro-indéno[10,2 b]fluorène à base de bore et d'azote comme accepteurs d'électrons dans des cellules photovoltaïques organiques (PVO). La piètre efficacité observée de ces dérivés pourrait être liée aux propriétés de leurs congénères réduits. Dans le cadre des présents travaux, nous faisons état de deux nouveaux membres de cette famille de composés que nous avons préparés par borylation électrophile de la 2,5 di p tolylpyrazine suivie d'une arylation de l'atome central de bore par des réactifs de type ZnAr2. Les deux dérivés que nous avons synthétisés, 1 (Ar = 2,4,6 F3C6H2) et 2 (Ar = C6F5), ont formé les anions radicalaires correspondants 1*- et 2*- par réduction chimique sous l'action du CoCp*2 et du CoCp2, respectivement. La comparaison des paramètres structuraux, ainsi que des données spectroscopiques et computationnelles, révèle que l'électron non apparié dans les anions radicalaires est localisé dans le noyau planaire de la molécule, ce qui défavorise la dimérisation. Toutefois, contrairement aux produits de départ neutres, les anions radicalaires 1*- et 2*- sont réactifs à l'air libre. Ces observations laissent donc supposer que les composés réduits sont stables aux processus de dégradation intrinsèques, mais qu'ils sont susceptibles de subir une dégradation extrinsèque lors du fonctionnement du dispositif. [Traduit par la Rédaction] Mots-clés : anions radicaux, bore, hétérocycles, Introduction Polycyclic aromatic molecules and polymers are well-studied materials for use in organic photovoltaic (OPV) or light-emitting devices. A subset of these materials consists of molecules and materials having one [...]

The problem of determining biologically active low-molecular-weight aminothiols, such as cysteine and glutathione, requires the development of new methods and analytical reagents. Among the latter substances, a group of spiropyrans can be distinguished, which are photochromic organic substances reaching an equilibrium between their cyclic and open forms in solutions. We consider a possibility of using benzofuran spiropyrans as analytical reagents for aminothiols and studied the effect of various substituents in their structure on the change in optical properties in the presence of cysteine and glutathione. An equilibrium in solutions of benzofuran spiropyrans bearing a hydroxyl group in position 7 shifts in the presence of analytes towards the formation of a colored open form. The considered spiropyrans were used to create a simple, selective, and sensitive procedure for the spectrophotometric and kinetic determination of cysteine and glutathione in vitro., Author(s): A. A. Shcherbatykh [sup.1] , O. I. Askalepova [sup.1] , A. O. Bulanov [sup.1] , I. N. Shcherbakov [sup.1] , S. T. Nguyen [sup.1] Author Affiliations: (1) grid.182798.d, 0000 [...]

The wettability and CV of mAC/Gt/PVA-GA and mAC/Gt/PVDF electrodes in 200 ppm NaCl solution at a scan rate of 5 mV·s−1. The variation of desalination capacity during 50 cycles for mAC/Gt/PVA-GA/Ti electrode.

In this work, the bismuth-terephthalate frameworks (Bi-BDC) were prepared by a facile solvothermal approach. The prepared Bi-BDC MOFs were characterized by XRD, TGA, FT-IR, SEM, and UV-vis DRS analyses. The results indicated that the synthesis temperature affected the crystallinity and morphologies of the Bi-BDC frameworks. Notably, the produced Bi-BDC at low temperatures (80 and 100 oC) exhibited enhanced light absorption ability. The photodegradation experiment of rhodamine (RhB) showed that the prepared Bi-BDC-100 sample had the highest removal efficiency of ca. ∼ 98% after 270 min of visible LED light illumination. In addition, the HPLC-MS analysis revealed that RhB was photocatalytically degraded over the Bi-BDC via the carboxylation and dealkylation mechanism. Furthermore, the removal efficiency of the organic pollutant was optimized by monitoring the effects of catalyst dosage, dye concentration, and pH media. Finally, cyclic tests implied that the synthesized Bi-BDC MOF had good stability and reusability.

Murrayafoline A (MuA) is a natural compound with diverse biological activities, including cytotoxicity against cancer cells, but suffers from poor water solubility and low specificity. In order to improve the potential of MuA as a candidate for cancer treatment, MuA-loaded liposomes were prepared with the liposomal membrane consisting of dioleoylphosphatidylcholine and cholesterol. Dynamic light scattering measurements showed that the MuA-loaded liposomes had a z-average particle size of 104.3 ± 6.4 nm (mean ± SD; n = 3) and a polydispersity index of 0.15 ± 0.02 (mean ± SD; n = 3). The encapsulation efficiency was 55.3 ± 2.3% (mean ± SD; n = 3). The in vitro cytotoxicity of encapsulated MuA was attenuated at IC50 = 21.97 µg/mL compared to 6.24 µg/mL for free MuA, against HepG2. In contrast, MuA-loaded liposomes were significantly more effective at inhibiting cell growth in HepG2 cancer spheroids, which indicated that they were able to reach the interior layers of the microtumor. Taken together, these results showed that the encapsulation of MuA in liposomes is a good research direction to improve this natural compound’s potential as a candidate for cancer treatment.

2-(2-Thiazolylazo)-p-cresol (TAC) reacts with Ni(II) at pH 6-10 and forms a 1 : 2 blue complex. The stability constant of this complex is 5.0 ± 0.3. The complex has maximum absorption at 600 nm with the molar absorptivity of 27063 L/mol cm. Two preconcentration methods for the determination of Ni (an extraction method and sorption onto an ion exchange resin) at ppm levels using a Ni-TAC complex in EtOH-H.sub.2O (1 : 1, v/v) are described. For the extraction method, the linear regression was y = 0.0375x - 0.0007, and the coefficient of determination (r.sup.2) was 0.9995. The limit of detection (LOD) was 9 [micro]g/L, and the limit of quantification (LOQ) was 28 [micro]g/L. The assay recovery was 83 ± 6%, and the intermediate precision (relative standard deviation (RSD), %) was 2.3%. For the method including sorption onto an ion exchange resin, the linear regression was y = 0.0391x - 0.0001, and the coefficient of determination (r.sup.2) was 0.9995. The LOD and LOQ were 7 and 25 [micro]g/L, respectively. The assay recovery was 99 ± 6%, and the intermediate precision (RSD) was 2.2%. Sorption onto an ion exchange resin is simple and precise and offers higher recovery compared to the extraction method for Ni quantification. Based on the findings in the present study, the preconcentration method including sorption onto an ion exchange resin could be applied to the determination of Ni in wastewater., Author(s): Nguyen Quoc Thang [sup.1] , Le Van Tan [sup.1] Author Affiliations: (1) grid.448730.c, 0000 0004 0518 008X, Chemical Engineering Faculty, Industrial University of Ho Chi Minh City, , 70000, [...]

The alternative desalination technique of membrane capacitive deionization (MCDI) has emerged in the last 15 years and received a lot of research attention since then. By using a voltage applied between two electrodes covered with ion-exchange membranes, MCDI has attempted to challenge established methods such as reverse osmosis or electrodialysis. In this study, through the crosslinking of sulfosuccinic acid (SSA) and glutaric acid (GA) with polyvinyl alcohol (PVA), cation exchange membrane preparation and characterization were introduced. For the CDI system, membranes were chosen based on their water absorption and ion exchange properties. The PVA/SSA/GA composite (mass ratio of 100:5:5) had the best water adsorption and charge efficiencies that could be utilized for CDI application. The membrane’s ability to desalinate water was assessed using electrical properties such as total resistance, specific capacitance, and electro adsorption coated with the best ratio composite CEM. The salt absorption capacity of 19.06 mg·g−1 with stable performance was found to be encouraging.

Herein, the effect of three types of capping polymers, mercaptopropionic acid (MPA), polyethylene glycol (PEG), and starch on the photoluminescence of Mn(2+)-doped ZnSe (ZnSe:Mn) nanoparticles, has been investigated. ZnSe:Mn nanoparticles were successfully prepared with a green method of precipitation in aqueous solutions containing MPA, PEG, or starch as stabilizers. The X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy had proved the formation of ZnSe:Mn particles and the interaction between them and the capping agents. The resultant nanoparticles with different capping polymers were identical in optical property; however, photoluminescence quantum yields (PLQY) as well as the photoluminescence lifetime varied by capping agents. Starch-capped ZnSe:Mn nanoparticles had the biggest size compared to others, which was confirmed using transmission electron microscopy, dynamic light scattering, UV-Vis absorbance and Raman spectroscopy. Also, the PL intensity was significantly enhanced with starch-capped ZnSe:Mn nanoparticles. The PLQYs of starch archived 26%, which was 1.23 or 1.8 times lower than that of ZnSe:Mn nanoparticles capping with MPA or PEG, respectively. Furthermore, the highest decline of PL intensity was detected in PEG, which completely diminished in the 19th week, while both MPA and starch endowed ZnSe:Mn nanoparticles with outstanding PL lifetimes diminished over seven weeks.

The first copper-doped titanium-based amine-dicarboxylate metal-organic framework was synthesized by the solvothermal approach in this article, with a Cu2+/Ti4+ ratio of 0.15 (15% Cu/Ti-MOFs). X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectra, N2 adsorption-desorption studies, and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) were all used to identify the crystalline and properties of the semiconductors. The rate constants of 15% Cu/Ti-MOFs to degrade Rhodamine B (RhB) were roughly two times higher than NH2-Ti-MOFs. Furthermore, 15% Cu/Ti-MOFs photocatalysts remained stable after three cycles. The trapping test revealed that the principal active species in the degradation performance were hydroxyl radicals and holes.

Bimetallic metal-organic frameworks (MOFs) exhibit outstanding performance in a wide range of applications, including gas catalysis, adsorption, and luminescence sensor. The structure and properties of materials can be designed based on the variation of different metal ions, so this MOFs material system has unique properties. In this study, M/Fe-MOF bimetallic materials (M = Co, Cu, and Mg) were synthesized by solvothermal method and evaluated for photocatalytic activity in the degradation reaction of rhodamine B (RhB) organic pigments. The as-synthesized materials were characterized by using several physicochemical methods such as X-ray diffraction, fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), and UV-Vis diffuse reflectance spectra. The results show that the Co/Fe-MOF, Cu/Fe-MOF, and Mg/MOF materials have uniform grain grade, high crystallinity, with the surface area of 26.1, 25.9, and 25.9 m2/g, respectively. When modified with Co, Cu, and Mg, the crystal structure of Fe-MOF materials was unchanged, and all metal ions are inserted inside the structure of the material, as well as replacing Fe ions in the lattice crystals. At the same time, the modification also increases the light absorption in the visible light region and gives a high photocatalytic degradation of RhB organic pigments under visible light in the range of 85–92%.

Jackfruit is a fruit tree species distributed mainly in Southeast Asia and Brazil. The pulp and skin of jackfruit are widely used in various fields such as food, medicine, and interior decoration. However, the jackfruit processing into edible and usable products generates a large quantity of agricultural waste. In this review, we focused on summarizing the environmental applications of jackfruit waste in wastewater treatment. Specifically, the potential and application of activated carbon synthesized from jackfruit waste were assessed concerning the adsorption of organic dyes and metals from wastewater. In practical water treatment applications, the adsorption kinetic and isothermal models have been evaluated for activated carbon's suitability and adsorption capacity. This study acts as the basis for further development of the by-product materials to environmental treatment application and to reduce the negative impact of agricultural by-products on the environment.

Coenzyme Q (CoQ or ubiquinone) serves as an essential redox-active lipid in respiratory electron and proton transport during cellular energy metabolism. CoQ also functions as a membrane-localized antioxidant protecting cells against lipid peroxidation. CoQ deficiency is associated with multiple human diseases; CoQ10 supplementation in particular has noted cardioprotective benefits. In Saccharomyces cerevisiae, Coq10, a putative START domain protein, is believed to chaperone CoQ to sites where it functions. Yeast coq10 deletion mutants (coq10Δ) synthesize CoQ inefficiently during log phase growth and are respiratory defective and sensitive to oxidative stress. Humans have two orthologs of yeast COQ10, COQ10A and COQ10B Here, we tested the human co-orthologs for their ability to rescue the yeast mutant. We showed that expression of either human ortholog, COQ10A or COQ10B, rescues yeast coq10Δ mutant phenotypes, restoring the function of respiratory-dependent growth on a nonfermentable carbon source and sensitivity to oxidative stress induced by treatment with PUFAs. These effects indicate a strong functional conservation of Coq10 across different organisms. However, neither COQ10A nor COQ10B restored CoQ biosynthesis when expressed in the yeast coq10Δ mutant. The involvement of yeast Coq10 in CoQ biosynthesis may rely on its interactions with another protein, possibly Coq11, which is not found in humans. Coexpression analyses of yeast COQ10 and human COQ10A and COQ10B provide additional insights to functions of these START domain proteins and their potential roles in other biologic pathways.

Naturally occurring sinapic acid is a valuable synthon for many high-value applications (e.g. cosmetic, pharmaceutic) that can be found in numerous plants, especially Brasiccacea species (e.g. rapeseed, mustard). It has been demonstrated that alkaline extraction of matter rich in sinapic acid resulted in the conversion of sinapic acid into 6-hydroxy-5,7-dimethoxy-2-naphtanoic acid (DMNA). Although DMNA could be a potential alternative to petro-based naphtanoic acid used in polymers, untill now, no reliable (bio)synthetic procedure existed to synthesize it at the preparative-scale. Herein, starting from sinapic acid, we describe a very simple one-pot two-step chemo-enzymatic pathway to DMNA – and reaction intermediaries bislactone (BL) and thomasidioic acid (TA) – at gram scale using a simple filtration as purification step. Green metrics – Process Mass Index and EcoScale – have been determined to assess the sustainability of this new process. Finally, the antiradical activities of DMNA, BL and TA have been evaluated.

Vietnam is known as an agricultural country with a variety of agricultural crops. In addition to agricultural by-products, bio-waste is the by-product from livestock waste, forestry, industry, and daily life. They affect the soil, water, and air environment by self-degradation processes in the environment. Therefore, researchers have come up with ideas for the usage of the by-products to decrease the amount of waste and minimize the environmental effects. In Vietnam, the by-products were used by researchers to produce bio-ethanol, fertilizers, composites, and activated carbon (AC). AC is one of the materials used to rapidly reduce the number of agricultural by-products by researchers. The synthesis process is optimized for the highest yield, while the physicochemical properties are also clearly analyzed through the X-ray diffraction, Fourier transform infrared, and Bacterial endotoxin testing assays. The average recorded specific surface area was about 300 m2 g−1. The functional groups and surface structure showed that the material has an amorphous structure with –OH, –CH, –CC, –C═C, –C═O groups. The AC from agricultural waste had been studied and applied to treat pollutants present in water.

Triple quadrupole mass spectrometry was used for the direct, quick and quantitative determination of chlorpyrifos residue in bell peppers using the QuEChERS extraction method. The method was validated, and the parameters were confirmed to be within the regulated limits. The limit of detection was 2.6 [micro]g/kg with a linear dynamic range from 5 to 200 [micro]g/kg. The percent recoveries of fortified bell pepper samples at 5, 10, and 50 [micro]g/kg were 84.6, 99.9, and 98.5% with the relative standard deviations of 3.3, 1.8, and 0.6%, respectively. As a result, the bell pepper samples collected from markets in Ho Chi Minh city contained chlorpyrifos despite the fact that in 2019 the Ministry of Agriculture and Rural Development removed the pesticides containing chlorpyrifos from the list of pesticides permitted for use in Vietnam. This method is suitable for the determination of chlorpyrifos residue in bell peppers with high sensitivity, accuracy, good precision, rapid analysis, and high specificity in a complex matrix., Author(s): Van-Trong Nguyen [sup.1], Long-Ho Tran [sup.1] [sup.2], Thanh-Khue Van [sup.1], Dinh-Vu Le [sup.1] Author Affiliations: (1) grid.448730.c, 0000 0004 0518 008X, Faculty of Chemical Engineering, Industrial University of Ho [...]

This study develops a plastic cycle toward circular economy practice in Vietnam. First, we analyze inter-relationships between economic sectors and environmental issues concerning plastic waste in 2018. The research method integrates interdisciplinary balance with life cycle inventory, in which input–output (IO) table is both an econometric tool and original database to determine plastic IO between industries. As a result, over 60% of plastics after use was recycled for the production process (called recycled plastics) and nearly 40% of plastics after-use left the process (called disposed plastics). Within the recycled plastics, there was 10–15% of informal recycling collection from trade villages; within the disposed plastics, there was 13–18% unable to be collected and uncontrollably disposed to the environment. Then, we construct the plastic cycle, in which all the imported/domestic flows, single/multiple uses, and recycle/disposal flows are represented in proportional dimensions. This overall yet quantitative picture is an important data-driven basis for proposing plastic waste management solutions toward circular economy practice. As analyzed, the most challenge for waste management in Vietnam is to control single-use products (occupied 15.96% of total plastics) and indiscriminate waste in the environment (occupied 20.36% of total plastics). The case study for polyethylene terephthalate shows the need for expanding producer’s responsibilities to improve plastic recovery efficiency.

In this study, CsPb1–x MnxBr3–2x Cl2x (x = 0–0.5) nanoparticles were synthesized directly in toluene solvents at high temperature. This approach results in small-size nanoparticles, which can be used in photoelectric components without adding a filtration process to eliminate high-temperature solvents such as octadecene. The high content Mn2+-incorporated CsPb(Cl/Br)3 host is observed by strongly wideband emission at 592 nm of manganese d-states spin and orbital forbidden transition. After infiltration into mesoporous TiO2, the Mn2+ ion receives energy from the CsPb(Cl/Br)3 host (irradiated 405 nm light-emitting diode source) and effectively transfers to the TiO2 scaffold layer. As a result, a metal/semiconductor/metal planar structure photodetector with m-TiO2/CsPb1–x MnxBr3–2x Cl2x (x = 0–0.5) composite showed several figures of merit compared to bare m-TiO2 and m-TiO2/CsPbBr3 such as on/off ratio of 104 times, responsivity of 1.67 A·W−1, and detectivity of 4.42 × 109 Jones. The key factors contributing to the growth of the on/off ratio include the decreasing dark current and enhancing exciton energy and transportation due to the infiltration of CsPb1–x MnxBr3–2x Cl2x (x = 0–0.5) perovskite quantum dots into mesopores of the m-TiO2 scaffold layer.

Direct methanol fuel cell (DMFC) attracts much attention due to its high abundance, environmental friendliness, and convenient transportation and storage. In this study, a novel catalyst of Pt3Mo alloy nanoparticles (NPs) on non-carbon Ti0.8W0.2O2 support was synthesized by microwave-assisted polyol process. The characteristic of Pt3Mo NPS/Ti0.8W0.2O2 catalyst was determined by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electronic microscopy (SEM), energy-dispersive X-ray (EDX), and Brunauer-Emmett-Teller (BET) method. Pt3Mo NPs had an average diameter of approximate 5.18 nm and were uniformly anchored on Ti0.8W0.2O2 surface. The ratio of Mo in the Pt3Mo alloy was consistent with the theoretical value, which supported the effectiveness of the synthesis method. In addition, Pt3Mo/Ti0.8W0.2O2 electrocatalysts exhibited higher CO-like tolerance in methanol oxidation reaction (MOR) than commercial electrocatalysts, excellent catalytic activity, and strong durability after 2000 cycles. The synergistic effect of Pt-Mo alloy, and the strong interaction between the bimetallic Pt-Mo alloy and the mesoporous Ti0.8W0.2O2 support, could weaken the Pt-CO bond. Besides, the high corrosion resistance and superior electrochemical durability of TiO2-based oxide also contribute to the excellent stability of Pt3Mo/Ti0.8W0.2O2 electrocatalyst in harsh electrochemical media. These results revealed that this material could be a potential catalyst in DMFC technology.