In this study, we have investigated the structural, electronic, mechanical, and optical properties of ZnSbF3-I and ZnSbF3-II by altering the position of Zn and Sb through density functional theory (DFT) for the first time. The structural stability of both structures was confirmed by calculating formation enthalpy. A remarkable phenomenon has been observed from the electronic band structures analysis, whenever altering the atomic of Zn and Sb, which leads to a transition from semiconducting, ZnSbF3-I to metallic, ZnSbF3-II conductivity. The obtained bandgap value of ZnSbF3-I is of the order of 0.97 eV with indirect transition and the spin-orbit coupling (SOC) effect reduced the band gap energy to 0.49 eV. Density of states (DOS) curves revealed that the Sb-5p state is mainly responsible for this phase transition. The estimated elastic constants suggested that both phases are mechanically stable. By assessing the different elastic parameters, it can be concluded that both phases are mechanically ductile, machinable, isotropic, and soft in nature. A large value of bulk modulus for ZnSbF3-II indicates that it is harder and cannot be compressed as easily as ZnSbF3-I. The structures exhibit high efficiency in absorbing UV light. ZnSbF3-II's strong reflectivity in the infrared spectrum makes it an option to use for IR shielding. This study will guide further theoretical and experimental investigation.
{"title":"Atomic position dependent structural, electronic, mechanical and optical properties of ZnSbF3 fluoroperovskites","authors":"Tanmoy Kumar Ghosh , M.N.H. Liton , Arpon Chakraborty , M.K.R. Khan , M.S.I. Sarker","doi":"10.1016/j.mssp.2024.109065","DOIUrl":"10.1016/j.mssp.2024.109065","url":null,"abstract":"<div><div>In this study, we have investigated the structural, electronic, mechanical, and optical properties of ZnSbF<sub>3</sub>-I and ZnSbF<sub>3</sub>-II by altering the position of Zn and Sb through density functional theory (DFT) for the first time. The structural stability of both structures was confirmed by calculating formation enthalpy. A remarkable phenomenon has been observed from the electronic band structures analysis, whenever altering the atomic of Zn and Sb, which leads to a transition from semiconducting, ZnSbF<sub>3</sub>-I to metallic, ZnSbF<sub>3</sub>-II conductivity. The obtained bandgap value of ZnSbF<sub>3</sub>-I is of the order of 0.97 eV with indirect transition and the spin-orbit coupling (SOC) effect reduced the band gap energy to 0.49 eV. Density of states (DOS) curves revealed that the Sb-<em>5p</em> state is mainly responsible for this phase transition. The estimated elastic constants suggested that both phases are mechanically stable. By assessing the different elastic parameters, it can be concluded that both phases are mechanically ductile, machinable, isotropic, and soft in nature. A large value of bulk modulus for ZnSbF<sub>3</sub>-II indicates that it is harder and cannot be compressed as easily as ZnSbF<sub>3</sub>-I. The structures exhibit high efficiency in absorbing UV light. ZnSbF<sub>3</sub>-II's strong reflectivity in the infrared spectrum makes it an option to use for IR shielding. This study will guide further theoretical and experimental investigation.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"187 ","pages":"Article 109065"},"PeriodicalIF":4.2,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-15DOI: 10.1016/j.mssp.2024.109118
Hoang-Tien Cao, Jeng-Rong Ho, Pi-Cheng Tung, Hai-Ping Tsui, Chih-Kuang Lin
Semi-conductive silicon carbide (semi-SiC) wafers are essential in the semiconductor industry, but their high hardness and brittleness make traditional machining difficult. Electric discharge machining (EDM) is an alternative method for machining semi-SiC wafer. This study investigates the effects of discharge energy parameters, such as pulse-on time and peak current, on the surface and subsurface characteristics of semi-SiC wafers subjected to micro-EDM drilling. The machined surface and subsurface morphology and microstructure were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). SEM micrographs revealed the presence of craters, resolidified material, cracks, and micro-pores on the machined surface, influenced by the thermal energy generated during the EDM process. The material removal mechanisms identified include melting, vaporization, spalling, and oxidation. EDS analyses indicated a larger discharge energy led to an increase in carbon and oxygen concentrations on the machined surfaces, likely due to the decomposition of SiC and oxidation during EDM. XPS analysis identified the presence of graphite, SiO2, Cu particles, Cu2O, and CuO on the machined surface. TEM micrographs revealed three distinct regions in the subsurface, namely a recast layer, a heat-affected zone (HAZ), and the unaffected bulk SiC. These layers exhibited different microstructures, with the thickness of the recast layer and HAZ being dependent on the discharge energy. This study highlights the advantages of micro-EDM over other techniques, achieving a thin recast layer and minimal HAZ, thereby preserving the surface and subsurface integrity of the semi-SiC wafer.
半导电碳化硅（semi-SiC）晶片是半导体工业中不可或缺的材料，但由于其硬度高、脆性大，传统的加工方法很难加工。放电加工（EDM）是加工半碳化硅晶片的一种替代方法。本研究探讨了脉冲接通时间和峰值电流等放电能量参数对微电火花钻孔加工半 SiC 晶圆表面和亚表面特性的影响。使用扫描电子显微镜 (SEM)、能量色散 X 射线光谱 (EDS)、X 射线光电子能谱 (XPS) 和透射电子显微镜 (TEM) 对加工表面和次表面形态及微观结构进行了表征。扫描电镜显微照片显示，受电火花加工过程中产生的热能影响，加工表面出现了凹坑、分解材料、裂纹和微孔。材料去除机制包括熔化、汽化、剥落和氧化。EDS 分析表明，放电能量越大，加工表面的碳和氧浓度就越高，这可能是由于电火花加工过程中碳化硅的分解和氧化作用造成的。XPS 分析确定了加工表面存在石墨、SiO2、铜颗粒、Cu2O 和 CuO。TEM 显微照片显示了次表面的三个不同区域，即再铸层、热影响区 (HAZ) 和未受影响的整体 SiC。这些层表现出不同的微观结构，重铸层和热影响区的厚度取决于放电能量。与其他技术相比，这项研究凸显了微型放电加工的优势，即可以获得较薄的再铸层和最小的热影响区，从而保持半碳化硅晶片表面和次表面的完整性。
{"title":"Characterization of machined surface in semi-conductive SiC wafer subjected to micro-EDM drilling","authors":"Hoang-Tien Cao, Jeng-Rong Ho, Pi-Cheng Tung, Hai-Ping Tsui, Chih-Kuang Lin","doi":"10.1016/j.mssp.2024.109118","DOIUrl":"10.1016/j.mssp.2024.109118","url":null,"abstract":"<div><div>Semi-conductive silicon carbide (semi-SiC) wafers are essential in the semiconductor industry, but their high hardness and brittleness make traditional machining difficult. Electric discharge machining (EDM) is an alternative method for machining semi-SiC wafer. This study investigates the effects of discharge energy parameters, such as pulse-on time and peak current, on the surface and subsurface characteristics of semi-SiC wafers subjected to micro-EDM drilling. The machined surface and subsurface morphology and microstructure were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). SEM micrographs revealed the presence of craters, resolidified material, cracks, and micro-pores on the machined surface, influenced by the thermal energy generated during the EDM process. The material removal mechanisms identified include melting, vaporization, spalling, and oxidation. EDS analyses indicated a larger discharge energy led to an increase in carbon and oxygen concentrations on the machined surfaces, likely due to the decomposition of SiC and oxidation during EDM. XPS analysis identified the presence of graphite, SiO<sub>2</sub>, Cu particles, Cu<sub>2</sub>O, and CuO on the machined surface. TEM micrographs revealed three distinct regions in the subsurface, namely a recast layer, a heat-affected zone (HAZ), and the unaffected bulk SiC. These layers exhibited different microstructures, with the thickness of the recast layer and HAZ being dependent on the discharge energy. This study highlights the advantages of micro-EDM over other techniques, achieving a thin recast layer and minimal HAZ, thereby preserving the surface and subsurface integrity of the semi-SiC wafer.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"187 ","pages":"Article 109118"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Inducing post-transition metals in an oxide semiconductor system has a high potential for use in storage for neuromorphic computing. It is challenging to find a material that can be switched stably between multiple resistance states. This research explores the memristive properties of Sn (post-transition metal)-doped ZnO (SZO) thin films, emphasizing their application in memristor devices. The (magnetron sputtered) synthesized SZO thin films in the form of Ag/SZO/Au/Ti/SiO₂ device demonstrated a clear bipolar resistive switching (BRS) behavior with VSET and VRESET of 1.0 V and −0.75 V, respectively. The memristor could change between a high resistance state and a low resistance state with a high RON/OFF rate of 104, mimicking synaptic behaviors such as potentiation and depression. This switching is attributed to the formation and dissolution of Ag filaments within the SZO layer, influenced by the migration of Ag⁺ ions and the presence of oxygen vacancies. These vacancies facilitate the formation of conductive filaments under positive bias and their dissolution under negative bias. The endurance and retention tests showed stable switching characteristics, with the memristor maintaining distinct HRS and LRS over 100 cycles and retaining these states for over 5K seconds without significant degradation. Finally, the nonlinearity values for potentiation and depression were αp∼1.6 and αd ∼ -0.14, suggesting that the memristor may be more responsive to increasing synaptic weights in biological systems. The linearity response at a very small pulse width showed the device is more applicable for neuromorphic applications. The observed memristor combined with stable endurance and retention performance, suggests that this memristor structure could play a crucial role in the development of artificial synapses and memory technologies.
{"title":"Nonlinear and linear conductance modulation and synaptic plasticity in stable tin-zinc oxide based-memristor for neuro-inspired computing","authors":"Rajwali Khan , Shahid Iqbal , Fazal Raziq , Pardha Saradhi Maram , Sabyasachi Chakrabortty , Sambasivam Sangaraju","doi":"10.1016/j.mssp.2024.109111","DOIUrl":"10.1016/j.mssp.2024.109111","url":null,"abstract":"<div><div>Inducing post-transition metals in an oxide semiconductor system has a high potential for use in storage for neuromorphic computing. It is challenging to find a material that can be switched stably between multiple resistance states. This research explores the memristive properties of Sn (post-transition metal)-doped ZnO (SZO) thin films, emphasizing their application in memristor devices. The (magnetron sputtered) synthesized SZO thin films in the form of Ag/SZO/Au/Ti/SiO₂ device demonstrated a clear bipolar resistive switching (BRS) behavior with V<sub>SET</sub> and V<sub>RESET</sub> of 1.0 V and −0.75 V, respectively. The memristor could change between a high resistance state and a low resistance state with a high R<sub>ON/OFF</sub> rate of 10<sup>4</sup>, mimicking synaptic behaviors such as potentiation and depression. This switching is attributed to the formation and dissolution of Ag filaments within the SZO layer, influenced by the migration of Ag⁺ ions and the presence of oxygen vacancies. These vacancies facilitate the formation of conductive filaments under positive bias and their dissolution under negative bias. The endurance and retention tests showed stable switching characteristics, with the memristor maintaining distinct HRS and LRS over 100 cycles and retaining these states for over 5K seconds without significant degradation. Finally, the nonlinearity values for potentiation and depression were α<sub>p</sub>∼1.6 and α<sub>d</sub> ∼ -0.14, suggesting that the memristor may be more responsive to increasing synaptic weights in biological systems. The linearity response at a very small pulse width showed the device is more applicable for neuromorphic applications. The observed memristor combined with stable endurance and retention performance, suggests that this memristor structure could play a crucial role in the development of artificial synapses and memory technologies.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109111"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-15DOI: 10.1016/j.mssp.2024.109116
Nabeel Israr , Muhammad Awais Jehangir , Ammar M. Tighezza , Shamim Khan , G. Murtaza , Muhammad Saeed
Perovskites systems are leading the photovoltaic technology now a days. For the consistent renewable energy applications new materials required with the desirable properties. In this work six new materials are being predicted which may be very useful for the renewable energy applications. The full potential scheme of linearized augmented plane wave with the local orbitals is used for the calculations with the PBEsol GGA and mBJ potentials for the exchange-correlation effects. The structural and elastic parameters of A2BAuI6 (A = K or Rb or Cs, B = Sc or Y) are computed, and the responses exhibits that such compounds are stable, have a ductile nature, and are described by a high elastic anisotropy. The bandgaps were identified via the electrical band structure computations for A2BAuI6 (A = K, Rb, Cs; B = Sc or Y) compounds as 1.25 eV, 1.64 eV, 1.24 eV, 1.62 eV, 1.25 eV and 2.04 eV with TB-mBJ + SOC approach. The calculated compounds have much dispersion in their bands and minimal carrier effective mass. Lattice thermal conductivity () is computed via Slack's equation for all computed compounds are 0.29 × 1014 W/mK, 0.31 × 1014 W/mK, 0.29 × 1014 W/mK, 0.31 × 1014 W/mK, 0.39 × 1014 W/mK and 0.29 × 1014 W/mK, indicating a promising future for thermoelectric uses. The calculation of thermoelectric parameters, including the power factor, Seebeck coefficient, and figure of merit, serves another prospective purpose and confirms the potential high use of these materials in thermoelectric devices. Likewise, acceptable quality characteristics like long diffusion length, tunable band-gap, high mobility, am-bipolar charge transport, and high absorption reinforce these compounds which make them even more suitable for photovoltaic applications.
{"title":"The effect of PBEsol GGA and mBJ potentials on the structural, electronic, optical, elastic and thermoelectric properties of A2BAuI6 (A = K or Rb or Cs, B = Sc or Y)","authors":"Nabeel Israr , Muhammad Awais Jehangir , Ammar M. Tighezza , Shamim Khan , G. Murtaza , Muhammad Saeed","doi":"10.1016/j.mssp.2024.109116","DOIUrl":"10.1016/j.mssp.2024.109116","url":null,"abstract":"<div><div>Perovskites systems are leading the photovoltaic technology now a days. For the consistent renewable energy applications new materials required with the desirable properties. In this work six new materials are being predicted which may be very useful for the renewable energy applications. The full potential scheme of linearized augmented plane wave with the local orbitals is used for the calculations with the PBEsol GGA and mBJ potentials for the exchange-correlation effects. The structural and elastic parameters of A<sub>2</sub>BAuI<sub>6</sub> (A = K or Rb or Cs, B = Sc or Y) are computed, and the responses exhibits that such compounds are stable, have a ductile nature, and are described by a high elastic anisotropy. The bandgaps were identified via the electrical band structure computations for A<sub>2</sub>BAuI<sub>6</sub> (A = K, Rb, Cs; B = Sc or Y) compounds as 1.25 eV, 1.64 eV, 1.24 eV, 1.62 eV, 1.25 eV and 2.04 eV with TB-mBJ + SOC approach. The calculated compounds have much dispersion in their bands and minimal carrier effective mass. Lattice thermal conductivity (<span><math><mrow><msub><mi>K</mi><mi>L</mi></msub></mrow></math></span>) is computed via Slack's equation for all computed compounds are 0.29 × 10<sup>14</sup> W/mK, 0.31 × 10<sup>14</sup> W/mK, 0.29 × 10<sup>14</sup> W/mK, 0.31 × 10<sup>14</sup> W/mK, 0.39 × 10<sup>14</sup> W/mK and 0.29 × 10<sup>14</sup> W/mK, indicating a promising future for thermoelectric uses. The calculation of thermoelectric parameters, including the power factor, Seebeck coefficient, and figure of merit, serves another prospective purpose and confirms the potential high use of these materials in thermoelectric devices. Likewise, acceptable quality characteristics like long diffusion length, tunable band-gap, high mobility, am-bipolar charge transport, and high absorption reinforce these compounds which make them even more suitable for photovoltaic applications.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109116"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-15DOI: 10.1016/j.mssp.2024.109119
Dylan M. Evans, Clint D. Frye
We developed a process for the fabrication of tunable single crystal diamond micro- and nanopillars, with tip widths ranging from 40 to 460 nm, densities ranging from 0.5 to 53.5 pillars/μm2, and heights greater than 4.5 μm. A self-assembled Au nanodot ensemble etch mask was formed from an annealed Au thin film. The nanodot diameter and density can be tuned using the initial film thickness. The pillars were etched from the nanodot mask using an RIE O2 plasma, which has infinite selectivity for the diamond when applied at low RF powers (50 W). Finally, the pillars can be sharpened to ∼40 nm tip widths by annealing in air at 650 °C. These pillars can be used for applications such as field effect enhancement of diamond photocathode devices, enhancement of optical emission from N-V centers, and antireflective coatings.
{"title":"Formation of tunable diamond micro- and nanopillars for field effect enhancement applications","authors":"Dylan M. Evans, Clint D. Frye","doi":"10.1016/j.mssp.2024.109119","DOIUrl":"10.1016/j.mssp.2024.109119","url":null,"abstract":"<div><div>We developed a process for the fabrication of tunable single crystal diamond micro- and nanopillars, with tip widths ranging from 40 to 460 nm, densities ranging from 0.5 to 53.5 pillars/μm<sup>2</sup>, and heights greater than 4.5 μm. A self-assembled Au nanodot ensemble etch mask was formed from an annealed Au thin film. The nanodot diameter and density can be tuned using the initial film thickness. The pillars were etched from the nanodot mask using an RIE O<sub>2</sub> plasma, which has infinite selectivity for the diamond when applied at low RF powers (50 W). Finally, the pillars can be sharpened to ∼40 nm tip widths by annealing in air at 650 °C. These pillars can be used for applications such as field effect enhancement of diamond photocathode devices, enhancement of optical emission from N-V centers, and antireflective coatings.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"187 ","pages":"Article 109119"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-15DOI: 10.1016/j.mssp.2024.109104
Areej Zubair , Faisal Nawaz , Masood ul Hassan Farooq , Iqra Fareed , Muhammad Danish Khan , Zulfiqar Ali , Mariam Nawaz , Hafiza Sadia Anam , Muhammad Tahir , Faheem K. Butt
To address environmental and energy concerns, CoVO/WxOy nanocomposites are hydrothermally fabricated and their structural and chemical properties are examined using XRD and FTIR. The surface morphology and optical characteristics are investigated with the help of FESEM and UV–Visible spectroscopy, respectively. CoVO/WxOy exhibits increased photocatalytic efficacy towards methylene blue degradation, attributed to its unique properties. Furthermore, the interface of CoVO/WxOy follows a Z-scheme mechanism for efficient charge transfer, with ·OH− identified as the most reactive species. The composite catalyst also displays exceptional stability. CoVO/WxOy also presents the capability to produce H2 and O2 from water splitting at small overpotential values. These investigations are supported by small tafel slope, Cdl value and electrochemical active surface area. These findings suggest that CoVO/WxOy hold great promise for use in environmental remediation and sustainable energy generation.
{"title":"Novel CoVO/WxOy composites for methylene blue photodegradation and electrocatalytic applications","authors":"Areej Zubair , Faisal Nawaz , Masood ul Hassan Farooq , Iqra Fareed , Muhammad Danish Khan , Zulfiqar Ali , Mariam Nawaz , Hafiza Sadia Anam , Muhammad Tahir , Faheem K. Butt","doi":"10.1016/j.mssp.2024.109104","DOIUrl":"10.1016/j.mssp.2024.109104","url":null,"abstract":"<div><div>To address environmental and energy concerns, CoVO/W<sub>x</sub>O<sub>y</sub> nanocomposites are hydrothermally fabricated and their structural and chemical properties are examined using XRD and FTIR. The surface morphology and optical characteristics are investigated with the help of FESEM and UV–Visible spectroscopy, respectively. CoVO/W<sub>x</sub>O<sub>y</sub> exhibits increased photocatalytic efficacy towards methylene blue degradation, attributed to its unique properties. Furthermore, the interface of CoVO/W<sub>x</sub>O<sub>y</sub> follows a Z-scheme mechanism for efficient charge transfer, with <strong>·</strong>OH<sup>−</sup> identified as the most reactive species. The composite catalyst also displays exceptional stability. CoVO/W<sub>x</sub>O<sub>y</sub> also presents the capability to produce H<sub>2</sub> and O<sub>2</sub> from water splitting at small overpotential values. These investigations are supported by small tafel slope, C<sub>dl</sub> value and electrochemical active surface area. These findings suggest that CoVO/W<sub>x</sub>O<sub>y</sub> hold great promise for use in environmental remediation and sustainable energy generation.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109104"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-15DOI: 10.1016/j.mssp.2024.109099
Shaikh Parwaiz , Youngku Sohn , Mohammad Mansoob Khan
Photocatalytic conversion of solar energy into chemical energy is a prospective solution to the energy crisis and environmental challenges. MXenes, characterized by their unique surface features and physicochemical properties derived from their atomically thin layered structures, are becoming promising candidates for various photocatalytic applications. This review offers a concise analysis of the structure and categorization of MAX phases and MXenes. The discussion covers a succinct overview of different synthesis techniques employed in the preparation of MXenes, encompassing traditional HF etching methods, HF-free alternatives, additive-mediated synthesis, and direct synthesis. This study highlights MXenes and related heterostructures as photocatalysts for H2O splitting, CO2 reduction, N2 fixation, H2O2 generation, and pollutant degradation. We incorporated two complementary approaches, in-situ characterization methods, and first-principles calculations, in the following section to provide a better understanding. We conclude this review by offering insights into future directions and a concise summary of the potential applications of MXenes and MXene-based heterostructures in photocatalysis. This review could serve as a valuable reference for the design and fabrication of unique and promising MXene-based photocatalysts.
{"title":"Insights into MXenes and MXene-based heterostructures for various photocatalytic applications","authors":"Shaikh Parwaiz , Youngku Sohn , Mohammad Mansoob Khan","doi":"10.1016/j.mssp.2024.109099","DOIUrl":"10.1016/j.mssp.2024.109099","url":null,"abstract":"<div><div>Photocatalytic conversion of solar energy into chemical energy is a prospective solution to the energy crisis and environmental challenges. MXenes, characterized by their unique surface features and physicochemical properties derived from their atomically thin layered structures, are becoming promising candidates for various photocatalytic applications. This review offers a concise analysis of the structure and categorization of MAX phases and MXenes. The discussion covers a succinct overview of different synthesis techniques employed in the preparation of MXenes, encompassing traditional HF etching methods, HF-free alternatives, additive-mediated synthesis, and direct synthesis. This study highlights MXenes and related heterostructures as photocatalysts for H<sub>2</sub>O splitting, CO<sub>2</sub> reduction, N<sub>2</sub> fixation, H<sub>2</sub>O<sub>2</sub> generation, and pollutant degradation. We incorporated two complementary approaches, in-situ characterization methods, and first-principles calculations, in the following section to provide a better understanding. We conclude this review by offering insights into future directions and a concise summary of the potential applications of MXenes and MXene-based heterostructures in photocatalysis. This review could serve as a valuable reference for the design and fabrication of unique and promising MXene-based photocatalysts.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109099"},"PeriodicalIF":4.2,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142650617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.mssp.2024.109106
Heli Mistry , Shardul Vadalkar , Keyur N. Vyas , Prafulla K. Jha
Toxic gases such as carbon monoxide (CO), nitric oxide (NO) and ammonia (NH3) pose serious health and environmental risks. While existing toxic gas monitors are costly, two-dimensional (2D) materials have shown promise for gas sensing applications due to their high surface-to-volume ratios and sensitivity. Among these, α-CN has been identified as a potential candidate for gas adsorption mechanisms. This study investigates the adsorption performance α-CN surface with the decoration of nickel (Ni)-atom for CO, NO, and NH₃ toxic gases using state of art density functional theory (DFT) based first principles calculations. The results indicate that the Ni-decoration significantly enhances the adsorption performance of α-CN, as evidenced by highly negative adsorption energies. Therefore, the calculated recovery times are extremely long, suggesting that Ni-decorated α-CN is more suitable for the removal of these toxic gases rather than as a sensor. The structural and electronic properties, including projected density of states (PDOS), band structure, charge density diagrams and transfer mechanisms, have been thoroughly analyzed. Additionally, sensing properties such as work function and electrical conductivity, computed using semi-classical methods, have been evaluated to validate the effectiveness of the material.
{"title":"Adsorption mechanism of Ni decorated α-CN monolayer towards CO, NO, and NH₃ gases: Insights from DFT and semi-classical studies","authors":"Heli Mistry , Shardul Vadalkar , Keyur N. Vyas , Prafulla K. Jha","doi":"10.1016/j.mssp.2024.109106","DOIUrl":"10.1016/j.mssp.2024.109106","url":null,"abstract":"<div><div>Toxic gases such as carbon monoxide (CO), nitric oxide (NO) and ammonia (NH<sub>3</sub>) pose serious health and environmental risks. While existing toxic gas monitors are costly, two-dimensional (2D) materials have shown promise for gas sensing applications due to their high surface-to-volume ratios and sensitivity. Among these, α-CN has been identified as a potential candidate for gas adsorption mechanisms. This study investigates the adsorption performance α-CN surface with the decoration of nickel (Ni)-atom for CO, NO, and NH₃ toxic gases using state of art density functional theory (DFT) based first principles calculations. The results indicate that the Ni-decoration significantly enhances the adsorption performance of α-CN, as evidenced by highly negative adsorption energies. Therefore, the calculated recovery times are extremely long, suggesting that Ni-decorated α-CN is more suitable for the removal of these toxic gases rather than as a sensor. The structural and electronic properties, including projected density of states (PDOS), band structure, charge density diagrams and transfer mechanisms, have been thoroughly analyzed. Additionally, sensing properties such as work function and electrical conductivity, computed using semi-classical methods, have been evaluated to validate the effectiveness of the material.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109106"},"PeriodicalIF":4.2,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.mssp.2024.109085
Tianxinyu Bai, Shenwei Wang, Weifang Zhang, Lixin Yi
Perovskite light emitting diodes (PeLEDs) have emerged as a promising technology for new display applications due to their high color purity and precisely adjustable band gap. However, compared to green and red PeLEDs, blue PeLEDs suffer from lower luminous efficiency and stability. Traditionally, pure blue perovskite luminescence is achieved using mixed halogens, which often leads to phase separation issues. In this paper, we directly introduced RbBr and prepared RbxCs1-xPbBr3 (x = 0.5,0.6,0.7) thin films using thermal evaporation, achieving wavelength-tunable and stable blue light emission ranging from 477 nm to 489 nm.This is the first report of using thermal evaporation for the fabrication of RbxCs1-xPbBr3 films. PeLEDs based on these films exhibited stable electroluminescence under varying driving voltages. Operated continuously over 30 min at 6 V in ambient air with 36 % humidity, these devices showed superior spectral stability. Using pure bromine-based material RbxCs1-xPbBr3 (x = 0.5,0.6,0.7) in the light-emitting layer solves the problem of phase separation of mixed halogens and achieves blue-light emission. Additionally, the introduction of Rb+ distorts the crystal structure of perovskite. This distortion decreases the bond length of Pb-Br bonds, increases the bond energy, and raises the formation energy of halogen anion vacancies. As a result, the density of perovskite defect states decreases, and thus the stability is enhanced. This work represents a rare example of vacuum thermal-evaporation processed RbxCs1-xPbBr3 films and all-inorganic perovskite LEDs.
{"title":"Vacuum evaporation deposited RbxCs1-xPbBr3 thin films for spectrally tunable and stable all-inorganic blue light-emitting diodes","authors":"Tianxinyu Bai, Shenwei Wang, Weifang Zhang, Lixin Yi","doi":"10.1016/j.mssp.2024.109085","DOIUrl":"10.1016/j.mssp.2024.109085","url":null,"abstract":"<div><div>Perovskite light emitting diodes (PeLEDs) have emerged as a promising technology for new display applications due to their high color purity and precisely adjustable band gap. However, compared to green and red PeLEDs, blue PeLEDs suffer from lower luminous efficiency and stability. Traditionally, pure blue perovskite luminescence is achieved using mixed halogens, which often leads to phase separation issues. In this paper, we directly introduced RbBr and prepared Rb<sub>x</sub>Cs<sub>1-x</sub>PbBr<sub>3</sub> (x = 0.5,0.6,0.7) thin films using thermal evaporation, achieving wavelength-tunable and stable blue light emission ranging from 477 nm to 489 nm.This is the first report of using thermal evaporation for the fabrication of Rb<sub>x</sub>Cs<sub>1-x</sub>PbBr<sub>3</sub> films. PeLEDs based on these films exhibited stable electroluminescence under varying driving voltages. Operated continuously over 30 min at 6 V in ambient air with 36 % humidity, these devices showed superior spectral stability. Using pure bromine-based material Rb<sub>x</sub>Cs<sub>1-x</sub>PbBr<sub>3</sub> (x = 0.5,0.6,0.7) in the light-emitting layer solves the problem of phase separation of mixed halogens and achieves blue-light emission. Additionally, the introduction of Rb<sup>+</sup> distorts the crystal structure of perovskite. This distortion decreases the bond length of Pb-Br bonds, increases the bond energy, and raises the formation energy of halogen anion vacancies. As a result, the density of perovskite defect states decreases, and thus the stability is enhanced. This work represents a rare example of vacuum thermal-evaporation processed Rb<sub>x</sub>Cs<sub>1-x</sub>PbBr<sub>3</sub> films and all-inorganic perovskite LEDs.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109085"},"PeriodicalIF":4.2,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-13DOI: 10.1016/j.mssp.2024.109114
Abu Sadat Md. Sayem Rahman , Kazi Md Shorowordi
In this study, structural, mechanical, electronic and optical properties of non-toxic inorganic trigonal-KGeX3 (X = Br, I) perovskites are investigated by first-principles method. The trigonal-KGeX3 (X = Br, I) perovskites are found to be thermodynamically and mechanically stable. Both trigonal perovskites, KGeBr3 and KGeI3 are direct band gap semiconductors with band gaps of 2.46 eV and 1.45 eV respectively. KGeBr3 is well-suited for optoelectronic devices that operate in the ultraviolet (UV) range, while KGeI3 is very promising as a solar absorber layer in perovskite solar cells. The KGeI3 is found to be ductile and provides good optical absorbance in visible region. The findings presented in this article align well with the previous literature published on similar crystal structures. This study suggests that trigonal non-toxic K-based inorganic perovskites can be very good candidates for optoelectronic applications.
本研究采用第一原理方法研究了无毒无机三方-KGeX3（X = Br，I）包晶石的结构、机械、电子和光学特性。研究发现，三方-KGeX3（X = Br，I）包晶石具有热力学和机械稳定性。KGeBr3 和 KGeI3 这两种三方包晶都是直接带隙半导体，带隙分别为 2.46 eV 和 1.45 eV。KGeBr3 非常适合用于在紫外线（UV）范围内工作的光电设备，而 KGeI3 作为包晶太阳能电池的太阳能吸收层则大有可为。研究发现，KGeI3 具有延展性，在可见光区域具有良好的光学吸收性。本文的研究结果与之前发表的有关类似晶体结构的文献十分吻合。这项研究表明，三方无毒 K 基无机包晶可以很好地应用于光电领域。
{"title":"First-principles study of novel non-toxic trigonal KGeX3 (X=Br, I) perovskites: A potential for optoelectronic applications","authors":"Abu Sadat Md. Sayem Rahman , Kazi Md Shorowordi","doi":"10.1016/j.mssp.2024.109114","DOIUrl":"10.1016/j.mssp.2024.109114","url":null,"abstract":"<div><div>In this study, structural, mechanical, electronic and optical properties of non-toxic inorganic trigonal-KGeX<sub>3</sub> (X = Br, I) perovskites are investigated by first-principles method. The trigonal-KGeX<sub>3</sub> (X = Br, I) perovskites are found to be thermodynamically and mechanically stable. Both trigonal perovskites, KGeBr<sub>3</sub> and KGeI<sub>3</sub> are direct band gap semiconductors with band gaps of 2.46 eV and 1.45 eV respectively. KGeBr<sub>3</sub> is well-suited for optoelectronic devices that operate in the ultraviolet (UV) range, while KGeI<sub>3</sub> is very promising as a solar absorber layer in perovskite solar cells. The KGeI<sub>3</sub> is found to be ductile and provides good optical absorbance in visible region. The findings presented in this article align well with the previous literature published on similar crystal structures. This study suggests that trigonal non-toxic K-based inorganic perovskites can be very good candidates for optoelectronic applications.</div></div>","PeriodicalId":18240,"journal":{"name":"Materials Science in Semiconductor Processing","volume":"186 ","pages":"Article 109114"},"PeriodicalIF":4.2,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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