Laboratory experiments for basic chemistry

This manual contains six experiments covering four major areas of chemistry: physical, organic, inorganic, and analytical chemistry. The experiments are able to provide the students with skills and knowledge of handling, interpreting, and reporting chemical experiments. Each laboratory experiment in this manual comprises three major parts that are arranged systematically. Students are required to answer the pre-lab review prior to doing their experiment by following the proposed procedures. After the experiment, each student is required to produce a lab report and answer the post-lab questions in the results and discussions section

Recent Advancement in Metal-Organic Framework: Synthesis, Activation, Functionalization, and Bulk Production

Metal–organic framework (MOF) is an emerging hybrid material that possesses high surface area, narrow pore size distribution, and tuneable functionality. In recent years, MOF-based materials have been widely studied in various applications such as gas storage, gas separation, heterogeneous catalysis, and drug delivery. However, less emphasis has been placed on the fundamentals of MOF that are crucial to provide scientific knowledge for tailoring MOFs with desirable properties for commercial applications. This review discusses recent advancement in the MOF chemistry, in particular, synthesis, activation, functionalisation, and bulk production of MOFs. This review will be of great interest to the researchers and chemists actively involved in the field of MOFs production. Abbreviations: BBR: Building block replacement; BDC: 1,4-benzenedicarboxylate; BET: Brunauer–Emmett–Teller; BTC: 1,3,5-benzenetricarboxylate; Boc: Tert-butoxycarbonyl; Bpy: 4,4’-bipyridine; CFG: Carboxylic functional group; CTAB: Cetyltrimethylammoniumbromide; DABCO: 1,4-diazabicyclo[2.2.2]octane; DEF: N,N-diethylformamide; DMF: N,N-dimethylformamide; Dhybdc: 2,5-dihydroxy-1,4-benzenedicarboxylate; [EMIm]Br: 1-ethyl-3-methylimidazolium bromide; FIR: Fujian Institute of Research; H2BDC: 1,4-benzenedicarboxylic acid; H3BTC: 1,3,5-benzenetricarboxylic acid; H4TBAPy: 1,3,6,8-tetrakis(p-benzoic acid)pyrene; HKUST: Hong-Kong University of Science and Technology; ICP-MS: Inductively coupled plasma mass spectrometry; ILAG: Ion- and liquid-assisted grinding; Im: Imidazole ; IPA: Isophthalate; IRMOF: Isoreticular metal–organic framework; IUPAC: International Union of Pure and Applied Chemistry; LAG: Liquid-assisted grinding; LBL: Layer-by-layer; LIB: Lithium-ion battery; mesoMOF: Mesoporous metal–organic framework; MeIm: 2-methyimidazole; MIL: Matériaux de l’Institut Lavoisier; MixMOF: Mixed-linker metal–organic framework; MOF: Metal–organic framework; MTBS: Methyltributylammoniummethylsulfate; NH2BTC: 2-aminobenzene-1,3,5-tricarboxylate; NOTT: University of Nottingham; NU: Northwestern University ; PCD: Protection-complexation-deprotection; PCN: Porous coordination network; PCP: Porous coordination polymer; PIM: Polymer of intrinsic microporosity; PSD: Post-synthetic deprotection; PSM: Post-synthetic modification; PXRD: Powder X-ray diffraction; PyCHO: 2-pyridinecarboxaldehyde; RH: Relative humidity; SALE: Solvent-assisted linker exchange; SALI: Solvent-assisted ligand incorporation; scCO2: Supercritical carbon dioxide; STEM: Scanning transmission electron microscopy; STY: Space–time yield; TBHP: tert-butyl hydroperoxide; TMU: Tarbiat Modares University; UiO: Universitetet i Oslo; ZIF: Zeolitic imidazolate framewor

Recent Advances on Desalination Rate and Stability of Chloride Capturing Electrode for Electrochemical Deionization

Electrochemical deionization (EDI), as the next generation technique of Capacitive deionization (CDI), has attracted great attention in the desalination community due to its minimum energy requirement (in low/moderate salinity), the flexible scale of the infrastructure, zero secondary pollution, etc. Compared to conventionally carbon-based CDI, faradic electrode-based EDI can be much more advantageous in terms of desalination capacity and charge efficiency, which starts a new era in the CDI community. However, it was found that the development of faradic anion-capturing electrode is much slower than its counterpart, which has led to some serious issues like slow desalination rate, poor cycling stability. Therefore, our study focuses on strategies from both material and desalination cell aspects to enhance the desalination rate and stability of EDI to try to meet the requirement for practical application

Numerical study and optimization of GO/ZnO based perovskite solar cell using SCAPS

This paper focuses on the numerical study of hybrid organic-inorganic perovskite solar cells. It investigates the incorporation of a graphene oxide (GO) thin layer to enhance solar cell efficiency. The study demonstrates that the GO layer improves interaction with the absorber layer and enhances hole transportation, resulting in reduced recombination and diffusion losses at the absorber and hole transport layer (HTL) interface. The increased energy level of the Lower Unoccupied Molecular Orbital (LUMO) in GO acts as an excellent electron-blocking layer, thereby improving the VOC. The objective is to explore different structures of perovskite solar cells to enhance their performance. The simulated solar cell comprises a GO/FASnI3/TiO2/ZnO/ITO sandwich structure, with FASnI3 and ZnO thicknesses adjusted to improve conversion efficiency. The impact of thickness on device performance, specifically the absorber and electron transport layers, is investigated. The fill factor (FF) changes as the absorber and electron transport layers (ETL) increase. The FF is an important parameter that determines PSC performance since it measures how effectively power is transferred from the cell to an external circuit. The optimized solar cell achieves a short-circuit current density (JSC) of 27.27 mA/cm2 , an open-circuit voltage (VOC) of 2.76 V, a fill factor (FF) of 27.05% and the highest power conversion efficiency (PCE) of 20.39% with 400 nm of FASnI3 and 300 nm of ZnO. These findings suggest promising directions for the development of more effective GO-based perovskite solar cells

Photocatalytic Degradation of Sumifix Supra Blue BRF

Oxidative degradation of textile azo dye, Sumifix Supra Blue BRF (SSBBRF) in aqueous solution of suspended TiO2 with the presence of UV irradiation and H2O2 has been studied. The addition of H2O2 in the photocatalytic system can enhance the degradation degree of SSBBRF solution. However, H2O2 concentration that more that 5 x 10-4 mol/L would detriment the degradation process. Study on the kinetics of oxidative degradation of SSBBRF solution in the TiO2/UV or TiO2/H2O2/UV systems showed that the system were following the pseudo-first order reaction with the rate constant, k of the optimal system as 0.0434 min-1

Interface structure between Nb thin film and MgO(112) substrate: A first-principles prediction

The crystal orientation of ceramic substrates is an important factor affecting the interface structure of metal/ceramic composite materials. However, there is little information about the interface composed of metal films and ceramic substrates with a high-index plane. In this work, we predicted the interface structure between a Nb film and a MgO(112) substrate by calculating the interface separation works of different interface models by using the first-principles calculation method. The results showed that the preferred growth direction is Nb [120], and that the value of the interface separation work is 0.35 eV/Å2. The lattice mismatch between the film and substrate is less than 3%, implying that a coherent interface type is highly realizable in Nb/MgO(112). Furthermore, we analyzed the interface structures of Nb/MgO(100), Nb/MgO(110), Nb/MgO(111), and Nb/MgO(112) and found that the unique atomic configuration of the MgO substrate is the main factor determining the preferred interface structure of Nb/MgO

The preferred growth orientation of Ti thin film on MgO(100) substrate

Understanding the preferred growth orientation of metal films is of great significance for optimizing film properties and preparing films with special structures. However, early works mainly focused on the preferred growth orientations of FCC and BCC metal films, the preferred growth orientation of HCP metal films and its formation mechanism are unclear. In this work, Ti film was deposited on MgO(100) substrate by magnetron sputtering at 523 K. The preferred growth orientation of Ti film and its formation mechanism were studied by experiment and first-principles calculation. XRD results found the preferred growth orientations of Ti film on MgO(100) substrate were Ti(001), Ti(100), and Ti(101), with Ti(001) being the most favored. First-principles calculation results showed the preferred growth orientation of the Ti film on the MgO(100) substrate was determined by a combination of interface separation work and lattice strain

Enhancing photocatalytic activity of titanium dioxide through incorporation of MIL‐53(Fe) toward degradation of organic dye

Photocatalytic activity of titanium(IV) oxide (TiO2) can be enhanced through modification of its surface‐active sites. Here, iron(III) carboxylate [MIL‐53[Fe]]‐incorporated TiO2 (as MIL‐53(Fe)/TiO2) was prepared using a hydrothermal method. This material was then calcined at 500°C to obtain a MIL‐53(Fe)‐derived γ‐Fe2O3/TiO2 photocatalyst. A photocatalytic study of MIL‐53(Fe)/TiO2 and MIL‐53(Fe)‐derived γ‐Fe2O3/TiO2 toward cationic methylene blue (MB) and anionic methyl orange (MO) showed that MIL‐53(Fe)/TiO2 (0.25 wt%) and MIL‐53(Fe)‐derived γ‐Fe2O3/TiO2 (0.75 wt%) resulted the best degree of dye degradation. The MIL‐53(Fe)‐derived γ‐Fe2O3/TiO2 (0.75 wt%) composite for instance is capable of degrading almost 100% of 20‐ppm MB and MO, respectively, within 6 hr. Photocatalytic degradation of MB and MO was well fitted to the Langmuir‐Hinshelwood pseudo‐first order kinetics model, which indicates physisorption as the key partway that facilitates dye decomposition on the surface of a photocatalyst under UV‐A irradiation. This study provides new insights into the exploration of MILs/TiO2 materials for the environmental remediation and pollution control

Comparative Assessment of Moyog River Watershed and Malaysia Water Quality Index

Water is vital to the existence of all living organisms, but this invaluable resource is badly threatened by fast-growing human population and urbanization when increasing number of rivers are polluted due to the uncontrolled human activities. Here, we report the assessment of Water quality of Moyog river through the Malaysia Water Quality Index (NWQI) versus Canadian Water Quality Index (CWQI) as well as Biological Monitoring Work Party (BMWP) index. Sampling stations were set at Kg. Kibunut (KB), Kg. Notoruss (NT) and Kg. Babagon (BB) located in middle stream, as well as Kg. Kibabaig (KG) located in the lower stream of the Moyog river. NWQI shows that all the selected sites except KG fall under First Class category indicating an excellent water quality of the river. However, under CWQI, water quality for both MY, NT and BB falls into Second Class and Third Class, respectively, signifying a deterioration of water quality, and inconsistency of NWQI and CWQI in the water quality assessment. Besides, through BMWP index approach, a total of 538 individuals belonging to 8 orders, 17 families and 18 genera identified during the whole sampling event. The BMWP index is in good agreement with CWQI and this implies that a more stringent and holistic NWQI should be proposed for better assessment of river water quality in Malaysia

Water Quality for River Basins after Post Earthquake Event

An earthquake with a magnitude of 5.9 on the Richter Scale struck Ranau, Sabah, on the 5th of June, 2015. It was recorded as the most significant earthquake occurrence in Sabah and had many implications, such as casualties, house and facilities damages, minor injuries, and environmental disruptions. In addition, the combination of continuous heavy rainfall triggered mudflow through landslides, which impacted the river's quality and disrupted the local water supply. The degradation of water quality will be due to the excess rainwater that cannot be absorbed by the soil, bringing the remnants of landslides into the river. Therefore, this study aims to monitor and assess the water quality of selected rivers affected by the earthquake and the mudflow to ensure it is safe to be utilised by the local residents. A total of five affected rivers were studied by analysing their physicochemical parameters, namely pH, temperature, turbidity, dissolved oxygen (DO) and electrical conductivity (EC). The results indicated that the mudflow overall creates a turbid, foamy and smelly river. High turbidity readings associated with high suspended solids were detected on specific dates for respective river stations. The high readings were associated with the cause of mass fish death in Sungai Kadamaian. Next, Sungai Mesilou faced a high-temperature reading above two celcius, which was not favourable for aquatic life. Physically, Sungai Mesilou also became shallower and flowed slowly. However, overall monitoring data revealed that the river's water quality was in good condition, except for the high turbidity dates. Nevertheless, the water quality of the respective rivers can recover on its own with the drop in turbidity levels found by the end of the monitoring dates, specifically at Sungai Panataran (S1), Sungai Kadamaian (S3) and Sungai Mesilou (S4). Hence, the water quality of such rivers, in general, is practically good and safe