The present study intends to check which nanotube formation mechanism match the surface evolution on bulk Ti surface after soaked in hydrothermal treatment. Polished cp-Ti disks were hydrothermally immersed in various concentration NaOH for 1h, 2h, and 4h at 220°C. The SEM observations and XRD studies showed a sequence transformation from polished Ti surface into titanium oxide with plate shape and leave-like structure in the beginning. Bigger plates or leaves oxide then evolved into sodium titanate nanorods that finally became nanotubes as the immersing time lengthened. Apparently self-assembly and partial dissolution were the most applied mechanism to explained the sodium titanate formation. Plate and leaves-like oxide mainly formed by dissolution of Ti metal followed by precipitation of TiO6 in self-assemble manner as the resultant of reaction between Ti(OH)3
+ and OH−. While, nanorod and nanotube structure were produced by partial dissolution of leaves structure followed precipitation of sodium titanate by reaction of Na+ with HTiO3
− generated from OH-reaction with Ti metal and TiO6.
Sumbawa has the potential to transition into a smart city, utilizing solar energy as their main source of its alternative energy. Located in the tropical country of Indonesia, Sumbawa’s dry season lasts eight months, during which it sees a solar intensity of 4.51 watt/m2/h, making solar energy a promising resource for the area. Its level of abundance and no pollution attribute are the main factors that make solar energy an attractive renewable resource. Raw calculation showed that solar energy is able to provide massive amount of energy, while solar panel and photovoltaic can produce zero greenhouse gases when converting solar energy into electricity. However, the high initial cost of installing solar cells hinder popularization of it as an alternative energy source, meanwhile some of the substance materials that compose solar panel may have a negative impact on the environment. This study intends to review the potential for inexpensive semiconductor-based solar panels to be applied as independent source of lighting by analysing the cost and environmental impact. Discussion on simple chemical method without high cost equipment instalment is also highlighted in this work, which offers recommendation of methods that can contribute on lowering the production cost of solar panel.
The gypsy composite ceiling of the sisal fibre amplifier is a potential environmentally friendly alternative replacing the commercial gyssum without fiber or a gypsy sum reinforcing fiber synthesis. In this study, manufactured a gypsy composite ceiling of a Sumbawa sisal fiber with a faction composition of the volume of 65% of a gypsy, cement 29% and sisal fiber 6%. The direction of fiber is variated with four conditions namely continuous fibre (SC) fiber woven (SW), discontinuous fibre (SDC) and hybrid fiber (SH). As a comparison of the use of Gypsy board without fiber with a fraction of the volume of a gypsy 65% and cement 35%. Then carried out physical testing (density test and water absorption) and mechanical testing of broken forces (modulus of rupture/MOR) and bending strength (modulus of elasticity/MOE). The results of physical testing showed an increase in the the density of a gypsy board of the 1.17 g/cm3 to ± 1.71 g/cm3 after reinforced fiber and absorbent water ± 42.76% for all fiber board. For the mechanical properties of MOR and MOE the highest value is produced by specimen with a directional continuous fiber direction (SC) of 10.58 MPa and 3890.6 MPa. And the lowest is owned specimen with a random discontinuous fiber direction (SDC) of 5.05 MPa and 1530.2 MPa. However, the value of fracture and bending of the SDC specimen is still higher than the commercial gypsy board without fiber. Feasibility analysis is performed by comparing the physical and mechanical properties of JIS A 5417-1992 and ISO 8336-2017 standards.
Cu2ZnSnS4(CZTS) thin films fabricated by successive ionic layer adsorption and reaction (SILAR) method is a promising combination to actualize a low cost thin films Solar Cell (TFSC). Ionic exchange and rinsing time are critical point for ionic layer formation in SILAR method. The purpose of this study is to investigate the influence of cationic and anionic immersing time on the band gap energy of CZTS. Immersing time was varied into 10, 20, 30 and 40 seconds for both deposited and annealed samples, which annealing was conducted on 300°C for two hours. Deposited results showed a linear increase on band gap energy as cationic immersing time extended. Whereas, nonlinear increment with optimum band gap 1.35eV at 30 seconds immersion happened for anionic time variation samples. Annealed CZTS with cationic time variation also showed a linear increasing band gap. Meanwhile, annealed with anionic time variation showed a backward tendency of the deposited samples which the band gap decrease nonlinearly as anionic immersing time lengthened.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.