Wet Mixing Method Research Articles

Alpha-calcium sulfate hemihydrate incorporated with tri-calcium phosphate and hydroxyapatite bioceramics as potential scaffold for bone regeneration

The development of artificial grafts, including biodegradable materials and non-biodegradable ones, for bone regeneration is a significant advance in the field of biomaterial science. Notably, bioceramics such as calcium sulfate hemihydrate and calcium phosphates have attracted extensive attention from researchers due to their natural bone-like composition. However, some requirements related to mechanical properties, resorption ability, osteoinduction and osteoconduction of each bioceramics have not been effectively controlled to make them ideal materials for bone regeneration applications. In this study, composites of β-tricalcium phosphate, hydroxyapatite, and α-calcium sulfate hemihydrate (β-TCP/HA/α-CSH) were synthesized using wet mixing method in order to create a template that degrades in sync with bone growth, offer sufficient mechanical strength during healing process, and has appropriate setting time for precise surgical application. The β-TCP/HA compositional phase with the ratio of 80/20 (% in weight) would be used for the entire study meanwhile the influence of α-CSH on the behaviour of β-TCP/HA/α-CSH composites would be investigated. The successful preparation of β-TCP/HA/α-CSH composite was evaluated by FTIR, XRD, and SEM. In vitro testing has further demonstrated the commendable biodegradability of β-TCP/HA/α-CSH composites and its ability for cell adhesion and migration, suggesting that β-TCP/HA/α-CSH composites would be a promising biomaterial for bone engineering.

The influence of Multi-Layer Plastic Packaging (MPP) on the high-temperature performance of asphalt binders and mixtures using wet and dry mixing methods

ABSTRACT High temperatures, combined with heavy traffic loads, increase the risk of permanent deformation and reduce the useful lifespan of pavements, leading to a greater need for maintenance and rehabilitation activities throughout the pavement's service life. This study aims to evaluate the effectiveness of recycled thermoplastic additives, specifically Multi-Layer Plastic Packaging (MPP) materials, in enhancing the high-temperature performance of asphalt mixtures. MPP materials, including types such as Polyester, Polyethylene, Nylon, and Metalized Polyester, were used for binder modification in asphalt mixtures. The modification was conducted using both wet and dry methods. The physical and rheological properties of the modified binders were assessed at high temperatures to determine their impact on stiffness and resistance to permanent deformation. The results indicate that MPP materials significantly improve the high-temperature performance of asphalt mixtures by enhancing binder stiffness and resistance to permanent deformation, with the wet method proving more effective than the dry method. These findings highlight the need for developing practical guidelines for incorporating MPP materials in asphalt production in the future and underscore the importance of comprehensive studies on maintenance, rehabilitation, and overall pavement lifecycle costs.

High-value application of kaolin by wet mixing method in low heat generation and high wear-resistant natural rubber composites

In this study, a silane coupling agent and kaolin, a natural mineral resource, were introduced into the wet mixing process of natural rubber latex, the high wear-resistant and low-generation heat natural rubber composites were prepared. The sputtering, collision, and deposition of coupling agent/fillers/natural rubber latex mixed emulsion onto the roller effectively could break up the filler aggregates, enable fillers to be better infiltrated, distributed, and dispersed in the rubber. The effects of dry/wet mixing processes and the ratio of kaolin to silica on the crosslinking density, filler dispersion, extrusion rheological properties, gas barrier properties, dynamic mechanical properties and thermal stability of NR composites were investigated, and the silanization mechanism was summarized by FTIR and XRD. The experimental results showed that kaolin improved the crosslinking density and failure temperature, reduced the Payne effect, extrusion swell, and rolling resistance. Compared with 60 phr silica-filled natural rubber, the gas barrier property and wear resistance of 60 phr kaolin-filled natural rubber were improved by 64 % and 27 %, respectively, and the rolling resistance was reduced by 57 %. When the ratios of silica to kaolin were both 20:40, the crosslinking density, gas barrier property, and wear resistance of wet mixing were improved by 24 %, 45 %, and 9 %, respectively, compared with dry mixing. This study provided a new method for the high-value application of kaolin in wet mixing and green tires.

A Facile Scalable Strategy for Constructing Novel Robust Self‐Healing Glove Utilizing Nanoreinforced Thermoreversible Carboxylated Nitrile Butadiene Rubber

AbstractRecent decades have seen an increase in using self‐healing technology in fabricating multifunctional rubber materials, which incorporate intrinsic mechanisms. However, achieving commendable self‐healing efficiency while maintaining strength in thin rubber films remains challenging. Herewith, the preparation of self‐healing carboxylated nitrile butadiene rubber thin films is presented with 0.40 ± 0.05 mm thickness, reinforced with sustainable TEMPO‐oxidized cellulose nanofibers. The thin films are fabricated using wet mixing and casting methods and translated to prototype fabrication via dipping. The study involves the effect of varying zinc stearate and filler concentrations on healing efficiency via ionic mechanisms alongside other characterization techniques, such as chemical composition, surface morphology, cross‐link density, and thermal stability. The fabricated thin films exhibited a tensile strength of 5.38 MPa and an elongation‐at‐break of 518%. After undergoing a temperature‐induced healing process at 100 °C for 1 h, the healing efficiency for both properties reached 72% and 90%, respectively. Moreover, these films demonstrates the ability to heal repeatedly at the same fracture site over multiple cycles, maintaining a healing efficiency of over 45% after the third cycle. A glove prototype is fabricated and tested using water and air leakage tests to prove the self‐healing technology's successful transfer.

Enhancing interface adhesion between waterjet‐produced rubber powders and natural rubber by wet‐mixing method

AbstractThe addition of rubber powder (RP) to natural rubber (NR) matrix using the dry mixing method leads to uneven distribution and poor interface bonding while the wet mixing method is not feasible due to the hydrophobic nature of the RP surface. To address this issue, we developed a method for producing RP with weakened hydrophobicity on the surface by high‐pressure waterjet and successfully achieved even distribution of the waterjet‐produced rubber powders (WPRPs) in NR and strong interface adhesion between WPRPs and NR by the wet mixing method. The properties of NR/WPRP composites were tested and characterized carefully. When adding 6 phr of 140‐mesh WPRPs in the NR matrix, the tensile strength and elongation at break of the NR/WPRP composites were 30.2 MPa and 627.2%, respectively, which were 4% and 7% higher than NR without WPRPs. Moreover, the anti‐abrasion property of the NR/WPRP composite was also strengthened by the addition of WPRPs. Our findings demonstrate that recycling waste rubber through a reasonable recycling method can not only reduce material waste and alleviate environmental pollution but also enhance the performance of the raw rubber, which offers significant economic benefits.

The effect of Polyethylene Terephthalate (PET) plastic addition to AC-WC in a wet mixture on increase of asphalt stability

PET (Polyethylene Terephthalate) plastic is one of the most common types of plastic used in Indonesia. Its existence has contributed significantly to various sectors, including the food and beverage, cosmetic, pharmaceutical, and other consumer product packaging industries. However, the use of PET plastic also creates a number of impacts that need to be considered. PET (Polyethylene Terephthalate) plastic has become an attractive alternative in the construction industry in Indonesia, particularly in its use as an asphalt mixture in road construction. This study aimed to determine the effect of the addition of PET waste to the asphalt on the value of Marshall characteristics as well as the optimum asphalt content and plastic content in the AC - WC mixture. Basic testing of 4 %, 5 %, and 6 % (by weight of asphalt) PET plastic mixture with wet mixing method where PET plastic is put into hot asphalt and stirred until homogeneous. Marshall test data will go through Formality Test, Homogeneity Test, Two-Way ANOVA, Duncan Test, and Correlation Regression Analysis to get the 3D graph equation. The result is that PET plastic affects the asphalt mixture by increasing the stability value and MQ value, for flow, VFB, and VMA values have decreased. VIM value increased at 4 % level and decreased at 6 % level. From the ribbon graph, the optimum asphalt content for each percentage of PET content is obtained, namely 4 % PET KAO value of 6.2 %, 5 % PET KAO 6.25 %, and 6 % KAO 6.28 %. It can be concluded that the mixing of PET with asphalt in AC-WC mixtures can be maximum if the right percentage combination of asphalt and PET content. From the 3D Graphic Method, it results that the maximum use of plastic PET is at a content of 5.40 %, and an asphalt content of 6.35 %, will produce an asphalt stability of 1714.232 kN

Thermochemical heat storage performance of Fe-doped MgO/Mg(OH)2: Experimental and DFT investigation

MgO/Mg(OH)2 thermochemical heat storage system can realize large-scale energy storage by repetitive hydration/dehydration reactions to enhance the stability of solar energy utilization. However, slow interconversion and incomplete reactions caused by agglomeration restrict the cyclic heat storage capability of MgO/Mg(OH)2. In this work, a low-cost efficient Fe-doped MgO was prepared by a simple wet-mixing method and its energy released performance and kinetics in MgO/Mg(OH)2 heat storage progress were examined in a twin fixed-bed reactor and a simultaneous thermal analyzer. Additionally, density functional theory calculations were used to examine the impact of Fe on the mechanisms of MgO/Mg(OH)2 heat storage process. The results shows that when the molar ratio of MgO to Fe is 95:5, the energy released density of Fe-doped MgO is about 400 % higher than that of MgO after 10 heat storage cycles. In preparation process, the existence of Fe leads to the generation of MgFe2O4, which forms layered microstructure with the high specific surface area and pore volume and mitigates agglomeration behavior of MgO. It improves the cyclic stability of MgO and reduces the dehydration temperature of Mg(OH)2, and simultaneously the activation energy of the dehydration stage is reduced by 33.2 %. Fe enhances the interaction of H2O with the MgO surface and promotes the dissociation of H2O on Mg(OH)2 surface. Combined with economic analysis, Fe-doped MgO is a suitable material for MgO/Mg(OH)2 heat storage cycles.

Deoxynivalenol Detection beyond the Limit in Wheat Flour Based on the Fluorescence Hyperspectral Imaging Technique.

Deoxynivalenol (DON) is a harmful fungal toxin, and its contamination in wheat flour poses a food safety concern globally. This study proposes the combination of fluorescence hyperspectral imaging (FHSI) and qualitative discrimination methods for the detection of excessive DON content in wheat flour. Wheat flour samples were prepared with varying DON concentrations through the addition of trace amounts of DON using the wet mixing method for fluorescence hyperspectral image collection. SG smoothing and normalization algorithms were applied for original spectra preprocessing. Feature band selection was carried out by applying the successive projection algorithm (SPA), uninformative variable elimination (UVE), competitive adaptive reweighted sampling (CARS), and the random frog algorithm on the fluorescence spectrum. Random forest (RF) and support vector machine (SVM) classification models were utilized to identify wheat flour samples with DON concentrations higher than 1 mg/kg. The results indicate that the SG-CARS-RF and SG-CARS-SVM models showed better performance than other models, achieving the highest recall rate of 98.95% and the highest accuracy of 97.78%, respectively. Additionally, the ROC curves demonstrated higher robustness on the RF algorithm. Deep learning algorithms were also applied to identify the samples that exceeded safety standards, and the convolutional neural network (CNN) model achieved a recognition accuracy rate of 97.78% for the test set. In conclusion, this study demonstrates the feasibility and potential of the FHSI technique in detecting DON infection in wheat flour.

Impact of Superabsorbent Polymer on Shrinkage and Compressive Strength of Mortar and Concrete

This article aims to study the effects of mixtures with superabsorbent polymers (SAPs) when using different mixing methods. The mixing methods used in this study are the dry mixing method and wet mixing method. Autogenous shrinkage, total shrinkage, drying shrinkage, compressive strength, and curing sensitivity index values are investigated. The results show that mixtures with SAPs have reduced autogenous shrinkage and total shrinkage. Shrinkage is more effectively reduced by the dry SAP mixing method than the wet SAP mixing method. The compressive strength derived by the dry SAP mixing method is higher than that derived by the wet SAP mixing method.

Thermochemical heat storage performance and structural stability of SiO2-coated CaO particles under fluidization in CaO/Ca(OH)2 cycles

The decline in CaO/Ca(OH)2 heat storage performance of CaO-based material with the number of cycles due to its fast expansion and fragmentation is an problem in the fluidized bed reactor. In this paper, a novel SiO2-coated CaO particle was manufactured from limestone and silica sol via wet-mixing method. Exothermic performance (such as exothermic temperature, effective hydration conversion and volumetric energy density) and structural stability of SiO2-coated CaO particles in a fluidized bed reactor were studied. The effects of SiO2 addition and calcination temperature on the exothermic performance and structural stability were analyzed, respectively. The results show that the mass ratio of limestone to silica sol of 1:1 and calcination temperature of 850 °C are recommended for the preparation of SiO2-coated CaO. The SiO2 layer is observed on the surface of the CaO. SiO2-coated CaO particles exhibit superior structural stability than uncoated CaO particles. The SiO2 coating reduces the increase of average particle size during 10 cycles from 33 % to 11 %. After 10 heat storage cycles, SiO2-coated CaO particles achieve a reduction of 45.4 % in expansion rate and 48.5 % in attrition rate compared with uncoated CaO particles, respectively. The volumetric energy density of SiO2-coated CaO particles after 10 cycles is 33.2 % higher than that of uncoated CaO particles. The highest exothermic temperature of SiO2-coated CaO particles after 10 cycles reaches 455.4 °C (steam partial pressure @ 60 kPa). The SiO2-coated CaO seems a promising candidate for the CaO/Ca(OH)2 thermochemical heat storage in the fluidized bed rector.

The performance improvement of basketball shell prepared with nanomaterials modified rubber supported by wet mixing method

This study investigates the performance of rubber composite combined with carbon nanotubes to improve its physicochemical properties during the vulcanization process, thereby improving the quality of basketballs. Natural rubber and butyl rubber were mixed in a 7:3 ratio to prepare a rubber composite. Subsequently, the rubber composite was mixed with carbon nanotubes. The results demonstrate that the rubber nanocomposite prepared using wet mixing exhibits thermal aging resistance. Furthermore, the rubber nanocomposite demonstrates excellent vulcanization characteristics, which can achieve a reduction in the cure time of the rubber nanocomposite exceeding 10%. Additionally, the rubber nanocomposite shows good compatibility and mechanical properties, such as elongation at break, hardness, swelling coefficient, and cross-linking density. Notably, under high sulfur and low sulfur conditions, the decrease in tensile strength of the rubber nanocomposite is significantly smaller compared to that under the normal conditions, indicating a substantial enhancement in flexural resistance for this rubber nanocomposite. In conclusion, the prepared rubber nanocomposite shows an improvement in mechanical properties, which holds valuable implications for enhancing the quality of rubber basketballs and promoting applications of rubber products.

Preparation and antibacterial properties of β-SiAlON/AlN composite ceramics

In this study, β-SiAlON/aluminum nitride (AlN) composite ceramics were synthesized using a wet-mixing method at 1500 °C under a N2 atmosphere. X-ray diffraction and scanning electron microscopy were used to characterize the ceramics before and after immersing them in water for 7 d. The change in pH and release of ammonia nitrogen were studied to investigate the reaction and antibacterial mechanisms of AlN hydrolysis. The effects of the AlN content on the phase composition, microstructure, chemical properties, and antibacterial efficacy of the composite ceramics were investigated. As the AlN content increased, the antibacterial efficiency gradually increased. The antibacterial efficiency of the composite ceramic with an AlN content of 60 wt% was 100%, indicating that an increase in pH and amount of ammonia nitrogen could synergistically enhance the antibacterial effect. However, in a lysogeny broth medium, the buffering effect of the culture medium and promotion of bacterial proliferation may reduce the antibacterial efficiency. Therefore, β-SiAlON/AlN composite ceramics show considerable potential for antibacterial applications.

Inorganic Fullerene-Like WS2 Reinforced Polyamide Powders for Improved Mechanical Properties in Laser Sintered Nanocomposite Parts

Polyamide (PA) is a widely utilized engineering polymer, and its thermal and mechanical properties can be further improved by adding nanofillers. However, adding inorganic fullerene-like tungsten disulfide (IF-WS2) nanoparticles (NPs) to PA to produce composite precursor powders for additive manufacturing is challenging. Here, we report a novel and cost-effective method for fabricating PA-12 based nanocomposite (NC) powders with fixed/partially encapsulated IF-WS2 nanoparticulate fillers utilizing an advanced mixing technique because simple wet mixing (WM) can only attach fillers weakly to the powder surfaces when compared to the proposed method. The resulting nanocomposite powders maintained nearly the original particle size distribution of PA-12. They also exhibited improved rheological properties, melting, and crystallization behaviors compared with those prepared by the WM method. The laser-sintered PA-12 nanocomposite specimens revealed enhanced powder thermal stability and higher tensile strengths than pristine PA-12, validating the advantages of the novel technique for the fabrication of polyamide nanocomposite powders and their suitability for utilization in laser sintering additive manufacturing. These results demonstrate that high-performance engineered PA-12 nanocomposite components can be directly laser sintered, and this technique can potentially be extended to fabricate other engineered polymeric nanocomposite powders.

Effect of Sintering Temperature on BPSCCO Superconductor with Addition of Al2O3 Using Wet Mixing Method

Superconductors are materials that can conduct electric current without resistance. The application of superconducting materials in the field of transportation is the super-fast train or Magnetic Levitation (MagLev). BPSCCO added with Al2O3 nanoparticles has been successfully synthesized using the wet mixing method. In this study, variations in the sintering temperature (840 and 880oC) were carried out using the wet mixing method. The performance of BPSCCO with the addition of Al2O3 was carried out by testing XRD, SEM, and I-V. Based on the results of XRD characterization, the volume fraction, impurity, and crystal size respectively were 57.49% (BPSCCO-840), 38.96% (BPSCCO-880); 42.5% (BPSCCO-840), 38.96% (BPSCCO-880) and 21.38 nm (BPSCCO-840); 28.84 nm (BPSCCO-880). Based on the results of the SEM test, the sample slabs are regular and have little free space. Based on the I-V test results, the BPSCCO-840 sample has the highest electrical conductivity of 2.4x104 S/m at a current of 0.6 mA and the BPSCCO-880 sample has a conductivity of 2.8x104 S/m at a current of 0.3 mA

Influence of nanosized magnesia on the hydration of borehole-sealing cements prepared using different methods

Gas drainage is an effective technology for gas control in coal mines. A high borehole-sealing quality is the fundamental precondition for efficient gas drainage. The expansibilities of cement pastes used in borehole-sealing processes are critical for the borehole-sealing effect. Nanosized magnesia expansive agents are used to improve the expansibilities of cement pastes and improve the borehole-sealing effect. Nuclear magnetic resonance spectrometry and scanning electron microscopy were adopted to study the effects of nanosized magnesia on the hydration of borehole-sealing cements used with different preparation methods. The results showed that an increase in the mass fraction of the nanosized magnesia promoted cement hydration, and the mass fraction was positively correlated with the promotion effect. The use of different preparation methods did not change the water-phase distribution in the cement. When using the wet-mixing preparation method, nanosized magnesia promoted the induction, acceleration, and deceleration periods of hydration; when using the dry-mixing preparation method, the nanosized magnesia promoted the induction period of cement hydration, and the promotion effect was less obvious than that seen when using the wet-mixing method. When using the wet-mixing preparation method, the nanosized magnesia was uniformly dispersed, thus enlarging the surface area of the reaction, which provided more nucleation sites for the hydration products of the cement and therefore accelerated the hydration reaction. When using the dry-mixing preparation method, the nanosized magnesia powders were dispersed nonuniformly and aggregated. Under these conditions, only a few nanosized magnesia particles on the surfaces of the aggregated clusters took part in hydration, so only a small number of nucleation sites were provided for the hydration products of cement. This led to inconsistent hydration of cement pastes prepared using the dry-mixing method. The surface porosity of the cement prepared with the wet-mixing preparation method first decreased and then increased with increases in the mass fraction of the nanosized magnesia. The cement surface exhibited compact hydration products and few pores, and the surface was relatively smooth. In comparison, the surface porosity of the cement prepared using the dry-mixing method fluctuated with increasing mass fraction of the nanosized magnesia, resulting in a rough cement surface and microfractures on some surfaces. The two preparation methods both reduced the surface porosity of the cement. The wet-mixing preparation was more effective and consistent in improving the compactness of the cement than the dry-mixing preparation. These results provide important guidance on the addition of nanosized magnesia in borehole-sealing engineering and the selection of cement preparation methods, and they also lay a solid foundation for realizing safe and efficient gas drainage.

Preparation and properties of rice husk ash silica filled natural rubber

AbstractRice husk ash silica obtained from the chemical purification of rice husk ash is a bio‐based silica. As a sustainable raw material, the bio‐based silica has attracted much attention in recent years. It can be used to replace traditional carbon black and silica in tire rubbers. Our experimental results show that the bio‐based silica can bring similar mechanical properties and higher wet grip to natural rubber in comparison with traditional silica. The wet mixing method is successfully used to disperse the bio‐based silica in natural rubber latex, obtaining a bio‐based silica/natural rubber composite with higher abrasion resistance and lower rolling resistance than the composite prepared by traditional dry mixing. The mechanical properties of bio‐based silica/natural rubber composites depend on the silica loading and mixing methods. Mixing natural rubber and bio‐based silica through wet‐mixing method is a green and sustainable approach to the tread rubbers with excellent mechanical properties, low rolling resistance, high abrasion resistance, and wet grip.

Laboratory investigation of foamed concrete prepared by recycled waste concrete powder and ground granulated blast furnace slag

Foamed concrete is a primary choice for building envelopes due to its good thermal inertia, controllable density and excellent fire resistance. Because of the high carbon emissions and energy consumption, it has become an increasingly urgent need to find a material that can replace cement. In particular, how to effectively use solid waste is an important trend and a significant challenge. In this study, foamed concrete was prepared by recycled waste concrete powder (RP) and ground granulated blast furnace slag (GGBS) using wet foam mixing method. By measuring the stability time of preformed foam and setting process of paste, as well as the compressive strength, dry density, porosity and thermal conductivity of specimen, the effects of alkali activator dosage, CaCl2·6H2O dosage and foam content on the properties of foamed concrete were discussed. The pore structure and reaction mechanism were analyzed by means of image analysis and X-ray diffraction. The results indicate that the compressive strength of specimen increased and then decreased with the increase of alkali content, and reached the maximum value at 5% of alkali activator. But the porosity and dry density were less affected by the amount of alkali activator. The addition of CaCl2·6H2O significantly shortened the setting process of paste, which made the paste and preformed foam achieve a better matching state. Thus the compressive strength and thermal inertia were markedly improved, and the pores were effectively refined. Foamed concrete with different density grades can be prepared by changing preformed foam content. With the increase of foam content, compressive strength and thermal inertia were obviously decreased, and the pore distribution was gradually coarsening. Furthermore, the thermal conductivity and porosity conformed to ME2 model. The activity of both RP and GGBS can be effectively activated, the two played a coordinating and complementary role to achieve the effect of synergistic utilization of solid waste.

Experimental research on the preparation and properties of foamed concrete using recycled waste concrete powder

Foamed concrete was prepared mainly by recycled waste concrete powder (RP) using wet foam mixing method. By measuring the stability time of preformed foam and setting process of paste, as well as the compressive strength, dry density, porosity and thermal conductivity of specimen, the effects of water to solid ratio (W/S), RP content and foam dosage on the properties of foamed concrete were discussed. The pore structure and reaction mechanism were analyzed by means of image analysis and X-ray diffraction. The results indicate that with the increase of W/S, the viscosity of paste decreased and the setting time increased gradually. The paste and preformed foam achieved a good matching state when W/S was 0.8. Thus the specimen had a largest porosity. With the increase of RP content, the compressive strength decreased obviously. The maximum amount of RP can reach up to 70%. Foamed concrete with different density grades can be prepared by changing preformed foam content. With the increase of foam content, compressive strength and thermal inertia were obviously decreased, and the pore distribution was gradually coarsening. Due to its inert properties, RP mainly played a filling role in the foamed concrete, but it can still have a significant effect on the setting process of paste, as well as the compressive strength and thermal conductivity of specimen.

Initial state of excavated soil and rock (ESR) to influence the stabilisation with cement

This paper investigates the initial state of excavated soil and rock (ESR). These initial states include dry density, organic content, water content (Wc), cement content (Cc), liquid index (LI), dry or wet mixing method. Three ESRs collected from tunnelling projects and kaolin were used in this study to compare. The specimens (i.e., 50 mm in diameter and 100 mm in height) were prepared in the laboratory and cured at 7 and 14 days, and then assessed by the unconfined compressive strength (UCS) test. The analysis shows that the ratio of Wc/Cc is the primary factor to obtain different UCS for high LI ESR and a simple equation is proposed for quick prediction. For ESR with a more general LI, predictive equations are also proposed in terms of artificial neural network (ANN) and genetic programming (GP) for 7-days curing time. The results indicate that the both ANN models with Bayesian Regularization (BR) algorithm outperform ANN with Levenberg-Marquardt (LM) and GP model are accurate to predict UCS of mixtures.

Study on Optical Energy Gap and the Thickness of Boron Doped Graphenic Carbon (B-GC) Film Prepared by Nanospray Method

Graphenic carbon (GC) provides a potential ability as photovoltaic material due to its tunable properties. Here, we investigate the optical energy gap and the thickness of B-GC material as a p-type in solar cell application. The GC was prepared from old charcoal powders of coconut shells by heating process at 400°C and B-GC powders were prepared by wet mixing method using boric acid as B atom source. B-GC films were then prepared by employing nebulizer as a nanospraying method. All samples were examined through various characterization techniques such as X-Ray Diffarction (XRD), SEM cross section, and UV-Vis spectroscopy. The amorphous characteristic of B-GC is confirmed by broad peaks in XRD patterns, similar to that of reduced graphene oxide (rGO). The present of B along with O and dominant C elements is determined by SEM-EDX result. The B dopants affect the optical bandgap energy (Eg) of GC as an intrinsic material. The thickness of B-GC films was found to be thinner than in a previous study that used a similar method but different equipment. The average thickness of B-GC films is in the range of 127 to 420 nm, followed by an increase in the deposition time for 5 to 20 s. Estimation of the Eg value indicated that B-GC has an energy gap around 2 eV, which is most suitable as a window layer in solar cell applications.