Soil Chemical Analysis

Transparent electronics is today one of the most advanced topics for a wide range of device applications. The key components are wide bandgap semiconductors, where oxides of different origins play an important role, not only as passive component but also as active component, similar to what is observed in conventional semiconductors like silicon. Transparent electronics has gained special attention during the last few years and is today established as one of the most promising technologies for leading the next generation of flat panel display due to its excellent electronic performance. In this paper the recent progress in n- and p-type oxide based thin-film transistors (TFT) is reviewed, with special emphasis on solution-processed and p-type, and the major milestones already achieved with this emerging and very promising technology are summarizeed. After a short introduction where the main advantages of these semiconductors are presented, as well as the industry expectations, the beautiful history of TFTs is revisited, including the main landmarks in the last 80 years, finishing by referring to some papers that have played an important role in shaping transparent electronics. Then, an overview is presented of state of the art n-type TFTs processed by physical vapour deposition methods, and finally one of the most exciting, promising, and low cost but powerful technologies is discussed: solution-processed oxide TFTs. Moreover, a more detailed focus analysis will be given concerning p-type oxide TFTs, mainly centred on two of the most promising semiconductor candidates: copper oxide and tin oxide. The most recent data related to the production of complementary metal oxide semiconductor (CMOS) devices based on n- and p-type oxide TFT is also be presented. The last topic of this review is devoted to some emerging applications, finalizing with the main conclusions. Related work that originated at CENIMAT|I3N during the last six years is included in more detail, which has led to the fabrication of high performance n- and p-type oxide transistors as well as the fabrication of CMOS devices with and on paper.

Oxide Semiconductor Thin‐Film Transistors: A Review of Recent Advances

Thin film solar cells (TFSC) are a promising approach for terrestrial and space photovoltaics and offer a wide variety of choices in terms of the device design and fabrication. A variety of substrates (flexible or rigid, metal or insulator) can be used for deposition of different layers (contact, buffer, absorber, reflector, etc.) using different techniques (PVD, CVD, ECD, plasma-based, hybrid, etc.). Such versatility allows tailoring and engineering of the layers in order to improve device performance. For large-area devices required for realistic applications, thin-film device fabrication becomes complex and requires proper control over the entire process sequence. Proper understanding of thin-film deposition processes can help in achieving high-efficiency devices over large areas, as has been demonstrated commercially for different cells. Research and development in new, exotic and simple materials and devices, and innovative, but simple manufacturing processes need to be pursued in a focussed manner. Which cell(s) and which technologies will ultimately succeed commercially continue to be anybody's guess, but it would surely be determined by the simplicity of manufacturability and the cost per reliable watt. Cheap and moderately efficient TFSC are expected to receive a due commercial place under the sun.

Thin-film solar cells: an overview

Photoelectrochemical (PEC) water splitting for hydrogen production is a promising technology that uses sunlight and water to produce renewable hydrogen with oxygen as a by-product. In the expanding field of PEC hydrogen production, the use of standardized screening methods and reporting has emerged as a necessity. This article is intended to provide guidance on key practices in characterization of PEC materials and proper reporting of efficiencies. Presented here are the definitions of various efficiency values that pertain to PEC, with an emphasis on the importance of solar-to-hydrogen efficiency, as well as a flow chart with standard procedures for PEC characterization techniques for planar photoelectrode materials (i.e., not suspensions of particles) with a focus on single band gap absorbers. These guidelines serve as a foundation and prelude to a much more complete and in-depth discussion of PEC techniques and procedures presented elsewhere.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0884291400005653

Accelerating materials development for photoelectrochemical hydrogen production: Standards for methods, definitions, and reporting protocols

Biomass pyrolysis kinetics: A comparative critical review with relevant agricultural residue case studies

Fabrication of vacuum-evaporated SnS/CdS heterojunction for PV applications

Structural and optoelectronic properties of vacuum evaporated SnS thin films annealed in argon ambient

In the perspectives of fabricating a nontoxic and low-cost photovoltaic system, SnS has recently received considerable interest as a potential solar cell material. However, doped or undoped CdS has been extensively studied as a window material with p-SnS for the fabrication of a heterojunction solar cell. Because of the carcinogenic character of CdS, there is a prevailing need to search for an alternative window layer and scrutinize the performance of the heterojunction with p-SnS. In this work ZnO thin films were fabricated onto ITO using a galvanostatic electrodeposition approach from the dimethyl sulfoxide bath. The as-deposited ZnO films were subsequently annealed at 400 °C in argon ambiance to reduce the intermediate trap states and effective sintering. Finally, SnS thin films were grown onto the ZnO layer by thermally evaporating high-purity SnS powder. The photovoltaic properties of the SnS/ZnO heterojunction were investigated.

https://iopscience.iop.org/article/10.1088/0268-1242/24/2/025024/pdf

Fabrication of the SnS/ZnO heterojunction for PV applications using electrodeposited ZnO films

This study concerns utilizing commonly available agricultural wastes like mustard stalk, jute stalk, sesame stalk, wheat straw, bagasse, and rice husk in a proper and efficient way. As a part of this research, activated carbon has been prepared from these wastes by a two-stage activation process with a carbonization stage up to 325°C as a first stage followed by chemical activation using zinc chloride as an activation agent. The effects of temperature, time, and impregnation ratio on activation have been studied. The batch adsorption technique has been utilized to obtain information for treating effluents from the dye industry. Methylene blue dye has been chosen as the standard. Adsorption data have been modeled using the Freundlich and Langmuir adsorption isotherms and first- and second-order kinetic equations and intraparticle diffusion model. Specific surface area was determined by the methylene blue spot test. The results indicate that such carbons can be employed as low-cost alternatives to expensive...

Biswajit Ghosh

Papers

Fabrication of vacuum-evaporated SnS/CdS heterojunction for PV applications

Structural and optoelectronic properties of vacuum evaporated SnS thin films annealed in argon ambient

Fabrication of the SnS/ZnO heterojunction for PV applications using electrodeposited ZnO films

Production of Low-Cost Carbon Adsorbents from Agricultural Wastes and Their Impact on Dye Adsorption

Synthesis of SnS thin films via galvanostatic electrodeposition and fabrication of CdS/SnS heterostructure for photovoltaic applications