scholarly journals Rugometric and Microtopographic Inspection of Cr–Cr2O3Cermet Solar Absorbers

2007 ◽  
Vol 2007 ◽  
pp. 1-6 ◽  
Author(s):  
Manuel F. M. Costa ◽  
V. Teixeira
Keyword(s):  
Optical Properties ◽  
Structural Characteristics ◽  
Cost Effective ◽  
Energy Conversion Efficiency ◽  
Pvd Coatings ◽  
Solar Panels ◽  
Careful Evaluation ◽  
Solar Absorbers ◽  
Topographic Characteristics ◽  
Sputter Deposited

The development of new efficient and cost effective solar energy collectors and converters either quantum or thermal attracts great attention and effort in a number of research laboratories all over the world. Cr–Cr2O3cermet PVD coatings can be successfully employed in thermal converters. Their energy conversion efficiency depends on their chemical and physical structural characteristics and related optical properties like reflectance, emittance, solar light absorption, or absorptance and transmittance. Parameters such as roughness and topographic characteristics of the produced coatings will greatly influence their relevant optical properties. A careful evaluation of the coatings' roughness and their microtopographic inspection is fundamental. The Cr–Cr2O3cermet coatings sputter deposited on cooper and aluminium shows similar absorption (92%) but the first ones present a better emittance and higher waviness (over30%) with similar roughness. In comparison with commercially available solar panels with a slightly better absorption but worse emittance our coatings have a much lower waviness (∼150%) and roughly50%higher roughness.

scholarly journals Partial and Total Substitution of Zn by Mg in the Cu2ZnSnS4 Structure

Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 578
Author(s):  
Diana M. Mena Romero ◽  
David Victoria Valenzuela ◽  
Cristy L. Azanza Ricardo
Keyword(s):  
Thin Film ◽  
Optical Properties ◽  
Cost Effective ◽  
Energy Conversion Efficiency ◽  
Band Gap Energy ◽  
Fine Tuning ◽  
Secondary Phases ◽  
Solar Absorber ◽  
High Efficient ◽  
Earth Abundant

Cu 2 ZnSnS 4 (CZTS) is a quaternary semiconductor that has emerged as a promising component in solar absorber materials due to its excellent optical properties such as band-gap energy of ca. 1.5 eV and significant absorption coefficient in the order of 10 4 cm − 1 . Nevertheless, the energy conversion efficiency of CZTS-based devices has not reached the theoretical limits yet, possibly due to the existence of antisite defects (such as Cu Zn or Zn Cu ) and secondary phases. Based on electronic similarities with Zn, Mg has been proposed for Zn substitution in the CZTS structure in the design of alternative semiconductors for thin-film solar cell applications. This work aims to study the properties of the CZTS having Mg incorporated in the structure replacing Zn, with the following stoichiometry: x = 0, 0.25, 0.5, 0.75, and 1 in the formula Cu 2 Zn 1 − x Mg x SnS 4 (CZ-MTS). The semiconductor was prepared by the hot injection method, using oleylamine (OLA) as both surfactant and solvent. The presence and concentration of incorporated Mg allowed the fine-tuning of the CZ-MTS semiconductor’s structural and optical properties. Furthermore, it was observed that the inclusion of Mg in the CZTS structure leads to a better embodiment ratio of the Zn during the synthesis, thus reducing the excess of starting precursors. In summary, CZ-MTS is a promising candidate to fabricate high efficient and cost-effective thin-film solar cells made of earth-abundant elements.

Effect of Etchant Concentration on the Optical Properties and Surface Topography of MoO3 Selective Solar Absorber Thin Films

MRS Advances ◽  
2020 ◽  
Vol 5 (21-22) ◽  
pp. 1133-1143 ◽  
Author(s):  
R. Akoba ◽  
G. G. Welegergs ◽  
M. Luleka ◽  
J Sackey ◽  
N Nauman ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Cost Effective ◽  
Solar Absorptance ◽  
Solar Absorber ◽  
Solar Absorbers ◽  
Metal Oxide Nanostructures ◽  
Xrd Patterns ◽  
Solar Thermal Applications ◽  
Chemical Etchant

ABSTRACTA novel technique providing a cost effective sustainable wet chemical etching method of synthesizing black Moly thin films rapidly has been presented. A top- down method for fabricating MoO3 has been investigated to understand the effect of chemical etchant concentration on the structural, morphological and optical properties of the thin films on Mo substrates. The XRD patterns demonstrated the formation of Tugarinovite MoO2 films on Mo substrate after annealing at 500°C in a vacuum. In this work, we developed nanostructured MoO3 on Mo substrate solar absorber, with a high solar absorptance of over 89%. These results suggest that solar absorbers made from refractory metal oxide nanostructures can be used for solar thermal applications.

Deposition time dependent study of structural and optical properties of PbS thin films grown by CBD method

2020 ◽  
Vol 13 ◽  
Author(s):  
Minakshi Chaudhary ◽  
Yogesh Hase ◽  
Ashwini Punde ◽  
Pratibha Shinde ◽  
Ashish Waghmare ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Band Gap ◽  
Deposition Time ◽  
Secondary Growth ◽  
Cost Effective ◽  
Xrd Analysis ◽  
Structural Morphology ◽  
Glass Substrates ◽  
Cbd Method

: Thin films of PbS were prepared onto glass substrates by using a simple and cost effective CBD method. Influence of deposition time on structural, morphology and optical properties have been investigated systematically. The XRD analysis revealed that PbS films are polycrystalline with preferred orientation in (200) direction. Enhancement in crystallinity and PbS crystallite size has been observed with increase in deposition time. Formation of single phase PbS thin films has been further confirmed by Raman spectroscopy. The surface morphology analysis revealed the formation of prismatic and pebble-like PbS particles and with increase in deposition time these PbS particles are separated from each other without secondary growth. The data obtained from the EDX spectra shows the formation of high-quality but slightly sulfur rich PbS thin films over the entire range of deposition time studied. All films show increase in absorption with increase in deposition time and a strong absorption in the visible and sub-band gap regime of NIR range of the spectrum with red shift in band edge. The optical band gap shows decreasing trend, as deposition time increases but it is higher than the band gap of bulk PbS.

First-principles study on the electronic and optical properties of the orthorhombic CsPbBr3 and CsPbI3 with Cmcm space group

2021 ◽  
Author(s):  
Xianhao Zhao ◽  
Tianyu Tang ◽  
Quan Xie ◽  
like gao ◽  
Limin Lu ◽  
...  
Keyword(s):  
Optical Properties ◽  
Solar Cells ◽  
Energy Conversion ◽  
Conversion Efficiency ◽  
First Principles ◽  
Energy Conversion Efficiency ◽  
Space Group ◽  
Absorbing Materials ◽  
Halide Perovskites ◽  
Lead Halide

The cesium lead halide perovskites are regarded as effective candidates for light-absorbing materials in solar cells, which have shown excellent performances in experiments such as promising energy conversion efficiency. In...

scholarly journals Feasibility Study of the Cranial Implant Fabricated without Supports in Electron Beam Melting

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 496
Author(s):  
Khaja Moiduddin ◽  
Syed Hammad Mian ◽  
Wadea Ameen ◽  
Hisham Alkhalefah ◽  
Abdul Sayeed
Keyword(s):  
Electron Beam ◽  
Electron Beam Melting ◽  
Structural Characteristics ◽  
Cost Effective ◽  
Medical Industry ◽  
Detailed Review ◽  
Build Time ◽  
Cranial Implant ◽  
Cranial Implants ◽  
Fabrication Time

Additive manufacturing (AM), particularly electron beam melting (EBM), is becoming increasingly common in the medical industry because of its remarkable benefits. The application of personalized titanium alloy implants produced using EBM has received considerable attention in recent times due to their simplicity and efficacy. However, these tailored implants are not cost-effective, placing a tremendous strain on the patient. The use of additional materials as support during the manufacturing process is one of the key causes of its high cost. A lot of research has been done to lessen the use of supports through various types of support designs. There is indeed a noticeable paucity of studies in the literature that have examined customized implants produced without or minimal supports. This research, therefore, reports on the investigation of cranial implants fabricated with and without supports. The two personalized implants are evaluated in terms of their cost, fabrication time, and accuracy. The study showed impressive results for cranial implants manufactured without supports that cost 39% less than the implants with supports. Similarly, the implant’s (without supports) build time was 18% less than its equivalent with supports. The two implants also demonstrated similar fitting accuracy with 0.2613 mm error in the instance of implant built without supports and 0.2544 mm for the implant with supports. The results indicate that cranial implants can be produced without EBM supports, which can minimize both production time and cost substantially. However, the manufacture of other complex implants without supports needs further study. The future study also requires a detailed review of the mechanical and structural characteristics of cranial implants built without supports.

Analytic Optimization of Cost Effective Thermoelectric Generation on Top of Rankine Cycle

2013 ◽  
Author(s):  
Kazuaki Yazawa ◽  
Yee Rui Koh ◽  
Ali Shakouri
Keyword(s):  
Steam Turbine ◽  
Fuel Efficiency ◽  
Cost Effective ◽  
Rankine Cycle ◽  
Energy Conversion Efficiency ◽  
Design Parameters ◽  
Steam Temperature ◽  
Combined System ◽  
Fuel Consumption Rate ◽  
The Impact

Thermoelectric (TE) generators have a potential advantage of the wide applicable temperature range by a proper selection of materials. In contrast, a steam turbine (ST) as a Rankine cycle thermodynamic generator is limited up to more or less 630 °C for the heat source. Unlike typical waste energy recovery systems, we propose a combined system placing a TE generator on top of a ST Rankine cycle generator. This system produces an additional power from the same energy source comparing to a stand-alone steam turbine system. Fuel efficiency is essential both for the economic efficiency and the ecological friendliness, especially for the global warming concern on the carbon dioxide (CO2) emission. We report our study of the overall performance of the combined system with primarily focusing on the design parameters of thermoelectric generators. The steam temperature connecting two individual generators gives a trade-off in the system design. Too much lower the temperature reduces the ST performance and too much higher the temperature reduces the temperature difference across the TE generator hence reduces the TE performance. Based on the analytic modeling, the optimum steam temperature to be designed is found near at the maximum power design of TE generator. This optimum point changes depending on the hours-of-operation. It is because the energy conversion efficiency directly connects to the fuel consumption rate. As the result, physical upper-limit temperature of steam for ST appeared to provide the best fuel economy. We also investigated the impact of improving the figure-of-merit (ZT) of TE materials. As like generic TE engines, reduction of thermal conductivity is the most influential parameter for improvement. We also discuss the cost-performance. The combined system provides the payback per power output at the initial and also provides the significantly better energy economy [$/KWh].

Cost-effective diagnostic kits for selective detection of gaseous H2S

2021 ◽  
Author(s):  
Prabhpreet Singh ◽  
Navdeep Kaur
Keyword(s):  
Optical Properties ◽  
Cost Effective ◽  
Perylene Diimide ◽  
Selective Detection ◽  
Diagnostic Kits ◽  
Limited Scope

Bay-functionalization of perylene diimide (PDI) dye provide scope for modulating the optical properties of PDI. Symmetrical functionalization at 1,7-position of bay-region of PDI offered limited scope for tunability of photo...

scholarly journals SiC-TiC nanocomposite for bulk solar absorbers applications: Effect of density and surface roughness on the optical properties

2019 ◽  
Vol 191 ◽  
pp. 199-208 ◽  
Author(s):  
Hélène Aréna ◽  
Moustapha Coulibaly ◽  
Audrey Soum-Glaude ◽  
Alban Jonchère ◽  
Adel Mesbah ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Optical Properties ◽  
Solar Absorbers
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