Displaying publications 1 - 20 of 33 in total

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  1. Khan MA, Alias N, Khan I, Salama FM, Eldin SM
    Sci Rep, 2023 Jan 27;13(1):1549.
    PMID: 36707653 DOI: 10.1038/s41598-023-28741-7
    In this article, we developed a new higher-order implicit finite difference iterative scheme (FDIS) for the solution of the two dimension (2-D) time fractional Cable equation (FCE). In the new proposed FDIS, the time fractional and space derivatives are discretized using the Caputo fractional derivative and fourth-order implicit scheme, respectively. Moreover, the proposed scheme theoretical analysis (convergence and stability) is also discussed using the Fourier analysis method. Finally, some numerical test problems are presented to show the effectiveness of the proposed method.
  2. Yunus R, Ariff AR, Shuaib IL, Jelani AM, Alias NA, Abdullah J, et al.
    PMID: 17121310
    There is very little data regarding the factors related to intima-media thickness (IMT) of the common carotid artery in normal individuals in those with non-insulin diabetes mellitus and perimenopausal women in Southeast Asian countries. Ultrasound imaging evaluating the carotid artery IMT in those with diabetes and those on hormone replacement therapy (HRT) was performed beginning in August 2000 for a period of nearly two years at the Department of Radiology, Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia. A total of 153 participants were included. Significant differences between the women on HRT and not on HRT were IMT and systolic blood pressure. When comparing those with non-insulin dependent diabetes mellitus (NIDDM) and normal individuals, the significant differences were IMT, total cholesterol level, systolic blood pressure and diastolic blood pressure. IMT was high in those with NIDDM but not in those on HRT. Both those with NIDDM and those on HRT had associated dyslipidemia and systolic hypertension.
  3. Alias N, Ali Umar A, Sadikin SN, Ridwan J, Hamzah AA, Ali Umar MI, et al.
    ACS Omega, 2023 May 30;8(21):18874-18881.
    PMID: 37273642 DOI: 10.1021/acsomega.3c01236
    Perovskite solar cells have emerged as a potential energy alternative due to their low cost of fabrication and high power conversion efficiency. Unfortunately, their poor ambient stability has critically limited their industrialization and application in real environmental conditions. Here, we show that by introducing hexamine molecules into the perovskite lattice, we can enhance the photoactive phase stability, enabling high-performance and air-processable perovskite solar cells. The unencapsulated and freshly prepared perovskite solar cells produce a power conversion efficiency of 16.83% under a 100 mW cm-2 1.5G solar light simulator and demonstrate high stability properties when being stored for more than 1500 h in humid air with relative humidity ranging from 65 to 90%. We envisage that our findings may revolutionize perovskite solar cell research, pushing the performance and stability to the limit and bringing the perovskite solar cells toward industrialization.
  4. Awaluddin SM, Shahein NA, Che Abdul Rahim N, Mohd Zaki NA, Nasaruddin NH, Saminathan TA, et al.
    Int J Environ Res Public Health, 2021 Oct 17;18(20).
    PMID: 34682667 DOI: 10.3390/ijerph182010922
    This study aimed to determine the prevalence of anemia and factors associated with anemia among men in Malaysia. The researchers used data from the 2019 National Health and Morbidity Survey (NHMS). The hemoglobin levels of men aged 15 years and above who gave their consent was measured using the HemoCue® Hb 201+ System©. The majority of them (87.2%) were men aged 15-59 years, referred to as the younger age group in this study. The prevalence of anemia among men was 12.6% (95% confidence interval (CI): 10.9, 14.5). The prevalence was higher among older men (30.7%; 95% CI: 26.6, 35.1) than younger men (10.0%; 95% CI: 8.2, 12.2). Anemia among men was associated with older age (adjusted odds ratios (aOR) = 3.1; 95% CI: 2.1, 4.4) and those with diabetes (aOR = 1.5; 95% CI: 1.2, 2.1) via a logistic regression analysis. In conclusion, older men were more affected by anemia than younger men in this study. Anemia among older men in Malaysia is at the level of moderate to severe public health significance. The likelihood of developing anemia is increased among older men with diabetes compared to older men without diabetes. These often-overlooked issues among men need to be detected and treated early in order to prevent complications and improve their quality of life.
  5. AlDala'een NFD, Mohamad WNKW, Alias N, Ali AM, Shaikh Mohammed J
    Soft Matter, 2017 Dec 20;14(1):124-131.
    PMID: 29215674 DOI: 10.1039/c7sm01682d
    There is an increasing interest in bioinspired dynamic materials. Abundant illustrations of protein domains exist in nature, with remarkable ligand binding characteristics and structures that undergo conformational changes. For example, calmodulin (CaM) can have three conformational states, which are the unstructured Apo-state, Ca2+-bound ligand-exposed binding state, and compact ligand-bound state. CaM's mechanical response to biological cues is highly suitable for engineering dynamic materials. The distance between CaM globular terminals in the Ca2+-bound state is 5 nm and in the ligand-bound state is 1.5 nm. CaM's nanoscale conformational changes have been used to develop dynamic hydrogel microspheres that undergo reversible volume changes. The current work presents the fabrication and preliminary results of layer-by-layer (LbL) self-assembled Dynamic MicroCapsules (DynaMicCaps) whose multilayered shell walls are composed of polyelectrolytes and CaM. Quasi-dynamic perfusion results show that the DynaMicCaps undergo drastic volume changes, with up to ∼1500% increase, when exposed to a biochemical ligand trifluoperazine (TFP) at pH 6.3. Under similar test conditions, microcapsules without CaM also underwent volume changes, with only up to ∼290% increase, indicating that CaM's bio-responsiveness was retained within the shell walls of the DynaMicCaps. Furthermore, DynaMicCaps exposed to 0.1 M NaOH underwent volume changes, with only up to ∼580% volume increase. Therefore, DynaMicCaps represent a new class of polyelectrolyte multilayer (PEM) capsules that can potentially be used to release their payload at near physiological pH. With over 200 proteins that undergo marked, well-characterized conformational changes in response to specific biochemical triggers, several other versions of DynaMicCaps can potentially be developed.
  6. Abdul Latip LS, Ahmad Alias NA, Ariff AR, Shuaib IL, Abdullah J, Naing NN
    J Clin Neurosci, 2004 Nov;11(8):835-9.
    PMID: 15519858 DOI: 10.1016/j.jocn.2003.12.017
    Minor head injury in a developing country like Malaysia is managed by primary care physicians and/or medical assistants in district hospitals. These patients are seen initially in their local hospitals, which have at least an X-ray machine for the purpose of screening. This study aimed to guide these physicians to manage these patients at a primary care level. A cross-sectional study was conducted and the study revealed significant predictors of significant computed tomographic (CT) findings. The presence of a Glasgow coma scale (GCS) score of 14 or 13 was associated with the risk of developing significant CT findings compared to patients with a GCS of 15 (p<0.001). Thirty-seven out of 50 patients with GCS of 14 or 13 developed clinically significant brain injury on CT scan. Similarly, the presence of skull fracture was associated with the risk of developing CT abnormalities (p<0.001). Forty-two out of 51 patients with skull fracture developed clinically significant CT findings. Vomiting was associated with developing CT abnormalities (p=0.017). Twenty-seven out of 40 patients with vomiting showed significant CT findings. Soft tissue injury was also found to be associated with developing CT abnormalities (p=0.007). Therefore, we propose reclassifying minor head injury based on the GCS score. Patients with a GCS score of 15 were classified as having mild head injury, while patients with a GCS score of 13 or 14 were at higher risk of developing brain injury and therefore categorized as high risk mild head injury. This group requires emergency CT scan examination, especially when associated with non-motor vehicle accidents, abnormal central nervous system (CNS) examination, craniofacial injuries or skull fractures. They should be referred to a general surgical unit which can treat head injuries or a neurosurgical tertiary centre.
  7. Alias N, Saipol HF, Ghani AC
    J Food Sci Technol, 2014 Dec;51(12):3647-57.
    PMID: 25477631 DOI: 10.1007/s13197-012-0913-7
    A chronology of mathematical models for heat and mass transfer equation is proposed for the prediction of moisture and temperature behavior during drying using DIC (Détente Instantanée Contrôlée) or instant controlled pressure drop technique. DIC technique has the potential as most commonly used dehydration method for high impact food value including the nutrition maintenance and the best possible quality for food storage. The model is governed by the regression model, followed by 2D Fick's and Fourier's parabolic equation and 2D elliptic-parabolic equation in a rectangular slice. The models neglect the effect of shrinkage and radiation effects. The simulations of heat and mass transfer equations with parabolic and elliptic-parabolic types through some numerical methods based on finite difference method (FDM) have been illustrated. Intel®Core™2Duo processors with Linux operating system and C programming language have been considered as a computational platform for the simulation. Qualitative and quantitative differences between DIC technique and the conventional drying methods have been shown as a comparative.
  8. Man K, Kareem AM, Ahmad Alias NA, Shuaib IL, Tharakan J, Abdullah JM, et al.
    Singapore Med J, 2006 Mar;47(3):194-7.
    PMID: 16518552
    Computed tomography (CT) perfusion is a new method to diagnose ischaemic stroke especially in developing countries. It identifies the area and is useful to predict the size of final infarction. The aim of this study was to assess cerebral ischaemia with CT perfusion (CTP) among patients with acute ischaemic stroke in Hospital Universiti Sains Malaysia, a tertiary referral centre in a rural setting.
  9. Awang S, Alias N, DeWitt D, Jamaludin KA, Abdul Rahman MN
    Front Public Health, 2021;9:726647.
    PMID: 34869147 DOI: 10.3389/fpubh.2021.726647
    Cardiothoracic intensive care unit (CICU) nurses have shared the role and responsibility for ventilator-weaning to expedite decision-making in patient care. However, the actions taken are based on individual's unstructured training experience as there is no clinical practice guideline (CPG) for nurses in Malaysia. Hence, this study aims to design a CPG for the process of weaning from mechanical ventilation (MV) for a structured nursing training in a CICU at the National Heart Institute (Institut Jantung Negara, IJN) Malaysia. The Fuzzy Delphi Method (FDM) was employed to seek consensus among a panel of 30 experts in cardiac clinical practice on the guidelines. First, five experts were interviewed and their responses were transcribed and analyzed to develop the items for a FDM questionnaire. The questionnaire, comprising of 73 items, was distributed to the panel and their responses were analyzed for consensus on the design of the CPG. The findings suggested that the requirements expected for the nurses include: (a) the ability to interpret arterial blood gases, (b) knowledge and skills on the basics of mechanical ventilation, and (c) having a minimum 1-year working experience in the ICU. On the other hand, the CPG should mainly focus on developing an ability to identify criteria of patient eligible for weaning from MV. The learning content should focus on: (a) developing the understanding and reasoning for weaning and extubating and (b) technique/algorithm for extubating and weaning. Also, the experts agreed that the log book/competency book should be used for evaluation of the program. The CPG for structured nursing training at IJN in the context of the study is important for developing the professionalism of CICU nurses in IJN and could be used for training nurses in other CICUs, so that decision for ventilator-weaning from postcardiac surgery could be expedited.
  10. Taib MAA, Alias N, Jaafar M, Razak KA, Tan WK, Shahbudin IP, et al.
    Nanotechnology, 2020 Oct 23;31(43):435605.
    PMID: 32640434 DOI: 10.1088/1361-6528/aba3d8
    Arrays of TiO2 nanotubes (TiO2 NTs) with grassy surfaces were observed on titanium foil anodised at 60 V in fluorinated ethylene glycol (EG) with added hydrogen peroxide (H2O2). The grassy surface was generated by the chemical etching and dissolution of the surface of the TiO2 NTs walls, which was accelerated by the temperature increase on the addition of H2O2 . Upon annealing at 600 °C, the grassy part of the TiO2 NTs was found to consist of mostly anatase TiO2 whereas the bottom part of the anodic oxide comprised a mixture of anatase and rutile TiO2. The TiO2 NTs were then used to reduce hexavalent chromium (Cr(VI)) under ultraviolet radiation. They exhibited a rather efficient photocatalytic effect, with 100% removal of Cr(VI) after 30 min of irradiation. The fast removal of Cr(VI) was due to the anatase dominance at the grassy part of the TiO2 NTs as well as the higher surface area the structure may have. This work provides a novel insight into the photocatalytic reduction of Cr(VI) on grassy anatase TiO2 NTs.
  11. Dahalan F, Alias N, Shaharom MSN
    PMID: 36688221 DOI: 10.1007/s10639-022-11548-w
    Games have been used as a learning tool for centuries. Gamification and game-based learning are becoming more prominent in educational settings for several reasons. When it comes to learning, being focused and immersed can massively improve a student's experience. The purpose of this study is to map the emerging trends of gamification and game-based learning (GBL) in the Vocational and Education Training (VET) sector. For this purpose, a Systematic Literature Review was conducted through the three most relevant scientific databases - Web of Science, Scopus, ScienceDirect, and PubMed with Google Scholar as a supporting database. The obtained sample was further selected following the PRISMA guidelines with screening and eligibility processes conducted based on inclusion criteria that were defined with consideration to the research's aim. This review comprised seventeen studies. The findings revealed a growing interest in the Asian continents in research from 2020 onwards. Furthermore, most of the study is centred on vocational schools and colleges in the engineering and healthcare fields. According to the overview, the digital learning platform and simulation technology are the most promising tools used in the research. The findings support the conclusion that gamification and game-based learning can improve academic performance, engagement, and motivation in vocational education learners. As a result, this study suggests that more research is needed to determine the gamification strategies that are most suited for vocational education and learning.
  12. Nudin NFH, Ali AM, Ngah N, Mazlan NZ, Mat N, Ghani MNA, et al.
    C. R. Biol., 2017 Aug;340(8):359-366.
    PMID: 28888550 DOI: 10.1016/j.crvi.2017.08.003
    Plant breeding is a way of selection of a particular individual for the production of the progeny by separating or combining desired characteristics. The objective of this study was to justify different characteristics of Dioscorea hispida (Ubi gadong) varieties using molecular techniques to select the best variety for sustainable production at the farmer's level. A total of 160 germplasms of Ubi gadong were collected from different locations at the Terengganu and Kelantan states of Malaysia. Forty eight (48) out of 160 germplasms were selected as "primary" selection based on yield and other qualitative characters. Selected collections were then grown and maintained for ISSR marker-assisted genetic diversity analysis. Overall plant growth and yield of tubers were also determined. A total of 12 ISSR markers were tested to justify the characteristics of Ubi gadong varieties among which three markers showed polymorphic bands and on average 57.3% polymorphism were observed representing the highest variation among germplasms. The ISSR marker based on UPGMA cluster analysis grouped all 48 D. hispida into 10 vital groups that proved a vast genetic variation among germplasm collections. Therefore, hybridization should be made between two distant populations. The D. hispida is already proved as the highest starch content tuber crops and very rich in vitamins with both micro and macro minerals. Considering all these criteria and results from marker-assisted diversity analysis, accessions that are far apart based on their genetic coefficient (like DH27 and DH71; DH30 and DH70; DH43 and DH62; DH45 and DH61; DH77 and DH61; DH78 and DH57) could be selected as parents for further breeding programs. This will bring about greater diversity, which will lead to high productive index in terms of increase in yield and overall quality and for the ultimate target of sustainable Ubi gadong production.
  13. Saged AAG, Mohd Yusoff MYZ, Abdul Latif F, Hilmi SM, Al-Rahmi WM, Al-Samman A, et al.
    J Relig Health, 2020 Aug;59(4):1824-1837.
    PMID: 29484510 DOI: 10.1007/s10943-018-0572-8
    This paper studies the effect of Quranic therapy on psychological diseases and spiritual diseases. The experiments have been conducted on a random sample with 121 patients from both genders. The procedures that have been followed were different sessions with the patients, who were given some verses from the Holy Quran to listen within a specific period of time. After that, each patient was given a remedy program. This study aimed to measure the effectiveness and responsiveness of patients to receive treatment through Quran. This study highlighted the employment of a quantitative research, which achieved its objective through validity and reliability. The results of the effectiveness factor came after ability and willingness and gave a result of 92.6% for those who support the contention that the Quran has a significant healing influence. Also, some of the patients who regularly attended Quranic therapy sessions have been successfully cured, 81.8% of the sample believe that Quranic therapy sessions support their health needs. This study has empirically proved that the sound of the Holy Quran is an effective treatment for those who suffer from spiritual and psychological issues. Folk medicine and other traditional methods of treatment are important field of study that require further investigation. The study also illustrates that it's highly important for patient to have confidence in his doctor or healer. Furthermore, our results show that the ability and willingness positively and significantly are related to the effectiveness and responsiveness, also effectiveness positively and significantly related to the responsiveness. Therefore, the patients satisfied to receive treatment through Quran and they have the ability and willingness to do so as they believe that Quran is an essential part of their life.
  14. Azemin WA, Alias N, Ali AM, Shamsir MS
    J Biomol Struct Dyn, 2023 Mar;41(4):1141-1167.
    PMID: 34935583 DOI: 10.1080/07391102.2021.2017349
    Many studies reported that the activation of tumour suppressor protein, p53 induced the human hepcidin expression. However, its expression decreased when p53 was silenced in human hepatoma cells. Contrary to Tilapia hepcidin TH1-5, HepTH1-5 was previously reported to trigger the p53 activation through the molecular docking approach. The INhibitor of Growth (ING) family members are also shown to directly interact with p53 and promote cell cycle arrest, senescence, apoptosis and participate in DNA replication and DNA damage responses to suppress the tumour initiation and progression. However, the interrelation between INGs and HepTH1-5 remains unknown. Therefore, this study aims to identify the mechanism and their protein interactions using in silico approaches. The finding revealed that HepTH1-5 and its ligands had interacted mostly on hotspot residues of ING proteins which involved in histone modifications via acetylation, phosphorylation, and methylation. This proves that HepTH1-5 might implicate in an apoptosis signalling pathway and preserve the protein structure and function of INGs by reducing the perturbation of histone binding upon oxidative stress response. This study would provide theoretical guidance for the design and experimental studies to decipher the role of HepTH1-5 as a potential therapeutic agent for cancer therapy. Communicated by Ramaswamy H. Sarma.
  15. Khaw WF, Chan YM, Nasaruddin NH, Alias N, Tan L, Ganapathy SS
    BMC Public Health, 2023 Jul 18;23(1):1383.
    PMID: 37464344 DOI: 10.1186/s12889-023-16309-z
    BACKGROUND: In Malaysia, the previous mortality burden has been a significant concern, particularly due to the high prevalence of noncommunicable diseases (NCDs) as the leading cause of death. Estimates of mortality are key indicators for monitoring population health and determining priorities in health policies and health planning. The aim of this study was to estimate the disease burden attributed to 113 major diseases and injuries in Malaysia in 2018 using years of life lost (YLL) method.

    METHODS: This study included all deaths that occurred in Malaysia in 2018. The YLL was derived by adding the number of deaths from 113 specific diseases and multiplying it by the remaining life expectancy for that age and sex group. Data on life expectancy and mortality were collected from the Department of Statistics Malaysia.

    RESULTS: In 2018, there were 3.5 million YLL in Malaysia. Group II (NCDs) caused 72.2% of total YLL. Ischaemic heart disease was the leading cause of premature mortality among Malaysians (17.7%), followed by lower respiratory infections (9.7%), road traffic injuries (8.7%), cerebrovascular disease (stroke) (8.0%), and diabetes mellitus (3.9%).

    CONCLUSIONS: NCDs are a significant health concern in Malaysia and are the primary contributor to the overall burden of disease. These results are important in guiding the national health systems on how to design and implement effective interventions for NCDs, as well as how to prioritise and allocate healthcare resources. Key strategies to consider include implementing health promotion campaigns, adopting integrated care models, and implementing policy and regulatory measures. These approaches aim to enhance health outcomes and the managements of NCDs in Malaysia.

  16. Alias N, Ahmad Mazian M, Salleh AB, Basri M, Rahman RN
    Enzyme Res, 2014;2014:197938.
    PMID: 25093119 DOI: 10.1155/2014/197938
    Psychrophilic basidiomycete yeast, Glaciozyma antarctica strain PI12, was shown to be a protease-producer. Isolation of the PI12 protease gene from genomic and mRNA sequences allowed determination of 19 exons and 18 introns. Full-length cDNA of PI12 protease gene was amplified by rapid amplification of cDNA ends (RACE) strategy with an open reading frame (ORF) of 2892 bp, coded for 963 amino acids. PI12 protease showed low homology with the subtilisin-like protease from fungus Rhodosporidium toruloides (42% identity) and no homology to other psychrophilic proteases. The gene encoding mature PI12 protease was cloned into Pichia pastoris expression vector, pPIC9, and positioned under the induction of methanol-alcohol oxidase (AOX) promoter. The recombinant PI12 protease was efficiently secreted into the culture medium driven by the Saccharomyces cerevisiae α-factor signal sequence. The highest protease production (28.3 U/ml) was obtained from P. pastoris GS115 host (GpPro2) at 20°C after 72 hours of postinduction time with 0.5% (v/v) of methanol inducer. The expressed protein was detected by SDS-PAGE and activity staining with a molecular weight of 99 kDa.
  17. Khan TF, Sherazi ZA, Alias NA, Mahmood Z
    Ann Acad Med Singap, 1993 Mar;22(2):251-3.
    PMID: 8363342
    We present a 64-year-old Malay lady who had undergone a choledochoduodenostomy (CDD) two years ago for obstructive jaundice. She was admitted with jaundice and underwent ultrasonography, percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangio pancreatography (ERCP) and computed tomographic (CT) scanning of the liver and biliary tree. All the investigations confirmed a type IVa choledochal cyst. At operation, the grossly dilated biliary system was packed with a thick mucoid material and the mucosa of the bile ducts was visibly abnormal with scattered nodules. This mucoid material had caused occlusion of the entire biliary tree resulting in obstructive jaundice. To the best of our knowledge, this is probably the first report of obstructive jaundice caused by thick mucus. The peculiar management problems of this case and the risk of malignant change in choledochal cysts are discussed.
  18. Jaffar N, Mohd Faizal S, Selamat Z, Alias N
    Heliyon, 2023 Oct;9(10):e21047.
    PMID: 37876443 DOI: 10.1016/j.heliyon.2023.e21047
    The COVID-19 pandemic affected everyone's lives and general well-being worldwide, including young adults. Young adulthood is marked by a shift in various social areas including acquiring financial independence. As the pandemic was an exceptional scenario in all nations, there is a research gap in analysing how it would affect financial experiences of young adults, particularly the Muslim young adults. These individuals may face financial stress as a result of the COVID-19 pandemic due to their high level of financial strain. Furthermore, little is still known about the role that religiosity may play in the relationship between the financial strain and financial stress, notably during the pandemic. The objectives of this study were to examine the level of financial strain and financial stress of Muslim young adults, assess the effect of financial strain on financial stress of Muslim young adults and investigate the moderating effect of religiosity on the relationship between Muslim young adults' financial strain and financial stress during the COVID-19 pandemic. A survey of 230 Muslim young adults was conducted in Malaysia. Results showed that thirty percent of Muslim young adults fell under high level of financial strain while majority of them fell under high level of financial stress. Additionally, financial strain had a significant positive effect on the financial stress of Muslim young adults. This means that the more financially strained, the more Muslim young adults experienced financial stress during the COVID-19 pandemic. Religiosity, however, did not moderate the relationship between financial strain and financial stress. These results highlighted the significance of comprehending the level of financial strain and financial stress experienced by Muslim young adults during the COVID-19 pandemic. The results provided relevant parties insights in developing strategies for Muslim young adults to manage financial strain and financial stress to reduce the negative effect of the COVID-19 pandemic.
  19. Alias N, Hussain Z, Tan WK, Kawamura G, Muto H, Matsuda A, et al.
    Chemosphere, 2021 Nov;283:131231.
    PMID: 34144283 DOI: 10.1016/j.chemosphere.2021.131231
    An anodic film with a nanoporous structure was formed by anodizing niobium at 60 V in fluorinated ethylene glycol (fluoride-EG). After 30 min of anodization, the anodic film exhibited a "pore-in-pore" structure; that is, there were smaller pores growing inside larger pores. The as-anodized film was weakly crystalline and became orthorhombic Nb2O5 after heat treatment. The energy band gap of the annealed nanoporous Nb2O5 film was 2.9 eV. A photocatalytic reduction experiment was performed on Cr(VI) under ultraviolet (UV) radiation by immersing the nanoporous Nb2O5 photocatalyst in a Cr(VI) solution at pH 2. The reduction process was observed to be very slow; hence, ethylenediaminetetraacetic acid (EDTA) was added as an organic hole scavenger, which resulted in 100% reduction after 45 min of irradiation. The photocatalytic reduction experiment was also performed under visible light, and findings showed that complete reduction achieved after 120 min of visible light exposure.
  20. Muzakir SK, Alias N, Yusoff MM, Jose R
    Phys Chem Chem Phys, 2013 Oct 14;15(38):16275-85.
    PMID: 24000052 DOI: 10.1039/c3cp52858h
    The possibility of achieving many electrons per absorbed photon of sufficient energy by quantum dots (QDs) drives the motivation to build high performance quantum dot solar cells (QDSCs). Although performance of dye-sensitized solar cells (DSCs), with similar device configuration as that of QDSCs, has significantly improved in the last two decades QDSCs are yet to demonstrate impressive device performances despite the remarkable features of QDs as light harvesters. We investigated the fundamental differences in the optical properties of QDs and dyes using DFT calculations to get insights on the inferior performance of QDSCs. The CdSe QDs and the ruthenium bipyridyl dicarboxylic acid dye (N3) were used as typical examples in this study. Based on a generalized equation of state correlating material properties and photoconversion efficiency, we calculated ground and excited state properties of these absorbers at the B3LYP/lanl2dz level of DFT and analyzed them on the basis of the device performance. Five missing links have been identified in the study which provides numerous insights into building high efficiency QDSCs. They are (i) fundamental differences in the emitting states of the QDs in the strong and weak confinement regimes were observed, which explained successfully the performance differences; (ii) the crucial role of bifunctional ligands that bind the QDs and the photo-electrode was identified; in most cases use of bifunctional ligands does not lead to a QD enabled widening of the absorption of the photo-electrode; (iii) wide QDs size distribution further hinders efficient electron injections; (iv) wide absorption cross-section of QDs favours photon harvesting; and (v) the role of redox potential of the electrolyte in the QD reduction process.
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