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Rare earth metal based DES assisted the VPO synthesis for n-butane selective oxidation toward maleic anhydride

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Green Energy & Environment 2023年第6期8卷 1737-1752页

作者： muhammad faizan Yingwei Li Xingsheng Wang Piao Song Ruirui Zhang Ruixia Liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemInstitute of Process Engineering Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Zhengzhou Institute of Emerging Industrial Technology Zhengzhou450000China

Deep eutectic solvents(DESs) are now considered a new class of ionic liquid analogs that have been generously used in various ***, vanadium phosphorus oxide(VPO) catalysts are synthesized in combination with a deep eutectic solvent containing rare earth metal(rE-DES), and their catalytic performance in n-butane selective oxidation to produce maleic anhydride(MA) is evaluated. The rE-DES is produced from the interaction of choline chloride(ChCl) and rare earth metal salts(Cerium, Europium, Lanthanum, and Samarium metal salt)(ChCl:rE = 1:0.5–1:3) under mild conditions. It was found that DESs served as structural modifiers and electronic promoters during VPO synthesis. It regulated the chemical state of the catalyst surface, such as the vanadium valence state, acid-base properties, and ratios of V^(4+)/V^(5+),Lat–O/Sur–O and P/V. Various characterization techniques, such as FT-IR, DSC, XRD, SEM, EDS, TEM, Raman, TGA, NH3-TPD, and XPS,were used to examine its physical and chemical characteristics. These characteristics were correlated with the catalytic performance. The VPO catalyst modified by rE-DES showed a significant enhancement of n-butane conversion and MA selectivity while suppressing the selectivity of CO and CO_(2)as well as the CO/CO_(2)ratio compared to the unpromoted VPO catalyst. Especially for Ce-DES-VPO, it increased the n-butane conversion and MA mass yield up to approximately 11% and 10%, respectively. In addition, we evaluated the catalytic performance under different activation atmospheres.

关键词： earth anhydride vanadium

Progress of vanadium phosphorous oxide catalyst for n-butane selective oxidation

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Chinese Journal of Chemical Engineering 2022年第3期35卷 297-315页

作者： muhammad faizan Yingwei Li Ruirui Zhang Xingsheng Wang Piao Song Ruixia Liu Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemInstitute of Process Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The utilization of lighter alkanes into useful chemical products is essential for modern chemistry and reducing the CO_(2)***,n-butane has gained special attention across the globe due to the abundant production of maleic anhydride(MA).Vanadium phosphorous oxide(VPO)is the most effective catalyst for selective oxidation of n-butane to MA so ***,the VPO complex exists in more or less fifteen different structures,each one having distinct phase composition and exclusive surface morphology and physiochemical properties such as valence state,lattice oxygen,acidity etc.,which relies on precursor preparation method and the activation conditions of *** catalytic performance of VPO catalyst is improved by adding different promoters or co-catalyst such as various metals dopants,or either introducing template or structural-directing ***,new preparation strategies such as electrospinning,ball milling,hydrothermal,barothermal,ultrasound,microwave irradiation,calcination,sol-gel method and solvothermal synthesis are also employed for introducing improvement in catalytic *** in above-mentioned different aspects will be ascribed in current review in addition to summarizing overall catalysis activity and final *** analyze the performance of the catalytic precursor,the reaction mechanism and reaction kinetics both are discussed in this review to help clarify the key issues such as strong exothermic reaction,phosphorus supplement,water supplement,deactivation,and air/n-butane pretreatment *** to the various industrial applications of VPO.

关键词： N-butane selective oxidation Oxidation of light alkanes Vanadium phosphorus oxide(VPO) Maleic anhydride

Role of self-assembled molecules’anchoring groups for surface defect passivation and dipole modulation in inverted perovskite solar cells

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Chinese Physics B 2024年第10期33卷 108-115页

作者： Xiaoyu Wang muhammad faizan Kun Zhou Xinjiang Wang Yuhao Fu Lijun Zhang Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOECollege of Materials Science and EngineeringJilin UniversityChangchun 130012China

Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high *** these advantages,their efficiency is currently limited by excessive defects and poor carrier transport at the perovskite-electrode interface,particularly at the buried interface between the perovskite and transparent conductive oxide(TCO).Recent efforts in the perovskite community have focused on designing novel self-assembled molecules(SAMs)to improve the quality of the buried ***,a notable gap remains in understanding the regulation of atomic-scale interfacial properties of SAMs between the perovskite and TCO *** understanding is crucial,particularly in terms of identifying chemically active anchoring *** this study,we used the star SAM([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)as the base structure to investigate the defect passivation effects of eight common anchoring groups at the perovskite-TCO *** findings indicate that the phosphonic and boric acid groups exhibit notable *** groups fulfill three key criteria:they provide the greatest potential for defect passivation,exhibit stable adsorption with defects,and exert significant regulatory effects on interface *** anchoring groups exhibit enhanced passivation capabilities for defect energy levels due to their superior Lewis base properties,which effectively neutralize local charges near *** various defect types,iodine vacancies are the easiest to passivate,whereas iodine-substituted lead defects are the most challenging to *** study provides comprehensive theoretical insights and inspiration for the design of anchoring groups in SAMs,contributing to the ongoing development of more efficient inverted perovskite solar cells.

关键词： inverted perovskite solar cell defect passivation self-assembled molecule interface engineering first-principles calculation

Lightweight authentication protocol for e-health clouds in IoT-based applications through 5G technology

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Digital Communications and Networks 2021年第2期7卷 235-244页

作者： Minahil muhammad faizan Ayub Khalid Mahmood Saru Kumari Arun Kumar Sangaiah Department of Computer Science COMSATS University Islamabad Sahiwal Campus57000Pakistan Department of Mathematics Ch.Charan Singh UniversityMeerutUtter Paradesh250001India School of Computing Science and Engineering VIT UniversityVelloreTamil NaduIndia

Modem information technology has been utilized progressively to store and distribute a large amount of healthcare data to reduce costs and improve medical *** this context,the emergence of e-Health clouds offers novel opportunities,like easy and remote accessibility of medical ***,this achievement produces plenty of new risks and challenges like how to provide integrity,security,and confidentiality to the highly susceptible e-Health *** these challenges,authentication is a major issue that ensures that the susceptible medical data in clouds is not available to illegal *** smart card,password and biometrics are three factors of authentication which fulfill the requirement of giving high *** three-factor ECC-based authentication protocols on e-Health clouds have been presented so ***,most of the protocols have serious security flaws and produce high computation and communication ***,we introduce a novel protocol for the e-Health cloud,which thwarts some major attacks,such as user anonymity,offline password guessing,impersonation,and stolen smart card ***,we evaluate our protocol through formal security analysis using the Random Oracle Model(ROM).The analysis shows that our proposed protocol is more efficient than many existing protocols in terms of computation and communication ***,our proposed protocol is proved to be more efficient,robust and secure.

关键词： Authentication Security protocol IoT 5G e-health cloud

Energy Efficient Adaptive Request Medium Access Control Protocol for Wireless Sensor Networks

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Energy Efficient Adaptive Request Medium Access Control Prot...

作者： muhammad faizan Khan 华南理工大学

学位级别：硕士

Wireless Sensor Network（WSN）is an emerging technology with potential applications in the field of environment and industrial monitoring,health care systems,security systems,smart grid and smart home system and so *** is a distributed network and it is composed of a large number of shared,self-directed,small,low powered devices called sensor *** naturally composed of a large number of spatially distributed,petite,battery-operated,embedded devices that are networked to collectively collect,process and convey data to the *** it has restricted computing and processing *** presents a host of applications and is an emerging choice for wide scale *** thesis focuses on developing the energy efficient medium access control protocol for Wireless Body area sensor networks（WBANs）which is a branch of Wireless Sensor Networks（WSN）.Wireless Body Area Networks（WBANs）consist of a number of miniaturized wearable or implanted sensor nodes that are used to monitor important parameters of a patient over long duration of *** medical applications,these devices are implanted inside the human body to measure and transfer the real time data or audio ***,the applications are prone to many challenges like quality of service parameters,scalability,maintainability,network lifetime and many *** past,research has been carried out on a main challenge that WBANs faces that is of network lifetime,which can be controlled by efficiently utilizing energy of sensor *** efficiency is one of the most important factors that should be considered when developing a MAC protocol in *** protocol is basically an enhancement in the old *** protocol is developed by following many *** the previous protocols were thoroughly *** found some drawbacks in those *** drawbacks are thoroughly discussed in chapter *** the bases of those studies we propose a new protocol which not only addresses all th

关键词：

An enhanced scheme for mutual authentication for healthcare services

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Digital Communications and Networks 2022年第2期8卷 150-161页

作者： Salman Shamshad muhammad faizan Ayub Khalid Mahmood Saru Kumari Shehzad Ashraf Chaudhry Chien-Ming Chen Department of Computer Science COMSATS University IslamabadSahiwal Campus57000Pakistan Department of Mathematics Ch.Charan Singh UniversityMeerutUttar Pradesh250004India Department of Computer Engineering Faculty of Engineering and ArchitectureIstanbul Gelisim UniversityIstanbulTurkey College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao266590China Riphah School of Computing&Innovation(RSCI) Riphah International UniversityLahore CampusLahore 55150Pakistan Department of Mathematics University of Padua35131 PaduaItaly

With the advent of state-of-art technologies,the Telecare Medicine Information System(TMIS)now offers fast and convenient healthcare services to patients at their ***,this architecture engenders new risks and challenges to patients'and the server's confidentiality,integrity and *** order to avoid any resource abuse and malicious attack,employing an authentication scheme is widely considered as the most effective approach for the TMIS to verify the legitimacy of patients and the ***,several authentication protocols have been proposed to this *** recently,Chaudhry et *** that there are vulnerabilities of impersonation attacks in Islam et al.'s ***,they introduced an improved protocol to mitigate those security ***,Qiu et *** that these schemes are vulnerable to the man-in-the-middle,impersonation and offline password guessing ***,they introduced an improved scheme based on the fuzzy verifier techniques,which overcome all the security flaws of Chaudhry et al.'s ***,there are still some security flaws in Qiu et al.'s *** this article,we prove that Qiu et al.'s protocol has an incorrect notion of perfect user anonymity and is vulnerable to user impersonation ***,we introduce an improved protocol for authentication,which reduces all the security flaws of Qiu et al.'s *** also make a comparison of our protocol with related protocols,which shows that our introduced protocol is more secure and efficient than previous protocols.

关键词： Authentication protocol Security protocol Anonymous protocol Impersonation attack TMIS

Exploration of B-site alloying in partially reducing Pb toxicity and regulating thermodynamic stability and electronic properties of halide perovskites

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 130-138页

作者： Xinjiang Wang muhammad faizan Kun Zhou Hongshuai Zou Qiaoling Xu Yuhao Fu Lijun Zhang State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOECollege of Materials Science and EngineeringJilin UniversityChangchun 130012China College of Physics and Electronic Engineering Center for Computational SciencesSichuan Normal UniversityChengdu 610068China International Center of Computational Method and Software Jilin UniversityChangchun 130012China

Alloying strategies provide a high degree of freedom for reducing lead toxicity,improving thermodynamic stability, tuning the optoelectronic properties of ABX3 halide perovskites by varying the alloying element species and their *** the key role of B-site cations in contributing band edge states and modulating structure factors in halide perovskites,the partial replacement of Pb2+with different B-site metal ions has been *** several experimental attempts have been made to date,the effect of B-site alloying on the stability and electronic properties of halide perovskites has not been fully ***,we take cubic CsPbBr3 perovskite as the prototype material and systematically explore the effects of B-site alloying on Pb-containing *** to the presence or absence of the corresponding perovskite phase,the ten alloying elements investigated are classified into three types(i.e.,Type Ⅰ:Sn Ge,Ca,Sr;Type Ⅱ:Cd,Mg,Mn;Type Ⅲ:Ba,Zn,Cu).Based on the first-principles calculations,we obtain the following ***,these B-site alloys will exist as disordered solid solutions rather than ordered structures at room temperature throughout the composition ***,the alloying of Sn and Ge enhances the thermodynamic stability of the cubic perovskite host,whereas the alloying of the other elements has no remarkable effect on the thermodynamic stability of the cubic perovskite ***,the underlying physical mechanism for bandgap tuning can be attributed to the atomic orbital energy mismatch or quantum confinement ***,the alloying of different elements demonstrates the diversity in the regulation of crystal structure and electronic properties,indicating potential applications in photovoltaic s and self-trapped exciton-based light-emitting *** work provides theoretical guidance for using alloying strategies to reduce lead toxicity,enhance stability,and optimize the electronic properties of halide perovsk

关键词： lead-based halide perovskites alloying thermodynamic stability first-principles calculations optoelectronic applications

Influence of Local Cation Order on Electronic Structure and Optical Properties of Cation-Disordered Semiconductor AgBiS_(2)

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Chinese Physics Letters 2024年第10期41卷 61-69页

作者： Xiaoyu Wang muhammad faizan Yuhao Fu Kun Zhou Yilin Zhang Xin He David J.Singh Lijun Zhang State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOECollege of Materials Science and EngineeringJilin UniversityChangchun 130012China Department of Physics and Astronomy University of MissouriColumbiaMissouri 65211-7010USA

Site disorder exists in some practical semiconductors and can significantly impact their intrinsic properties both beneficially and ***,the uncertain local order and structure pose a challenge for experimental and theoretical ***,it hinders the investigation of the effects of the diverse local atomic environments resulting from the site *** employ the special quasi-random structure method to perform first-principles research on connection between local site disorder and electronic/optical properties,using cationdisordered AgBiS_(2)(rock salt phase)as an *** predict that cation-disordered AgBiS_(2)has a bandgap ranging from 0.6 to 0.8 eV without spin-orbit coupling and that spin-orbit coupling reduces this by approximately 0.3 *** observe the effects of local structural features in the disordered lattice,such as the one-dimensional chain-like aggregation of cations that results in formation of doping energy bands near the band edges,formation and broadening of band-tail states,and the disturbance in the local electrostatic potential,which significantly reduces the bandgap and *** influence of these ordered features on the optical properties is confined to alterations in the bandgap and does not markedly affect the joint density of states or optical *** study provides a research roadmap for exploring the electronic structure of site-disordered semiconductor materials,suggests that the ordered chain-like aggregation of cations is an effective way to regulate the bandgap of AgBiS_(2),and provides insight into how variations in local order associated with processing can affect properties.

关键词： stability structure ordered

Graphene photodetectors integrated with silicon and perovskite quantum dots

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Microsystems & Nanoengineering 2024年第3期10卷 21-33页

作者： Kashif Abbas Peirui Ji Naveed Ullah Shareen Shafique Ze Zhang muhammad faizan Ameer Shenghan Qin Shuming Yang State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Microelectronic Science and Engineering Laboratory of Clean Energy Storage and ConversionSchool of Physical Science and TechnologyNingbo Collaborative Innovation Center of Nonlinear Calamity System of Ocean and AtmosphereNingbo UniversityNingbo 315211China

Photodetectors(PDs)play a crucial role in imaging,sensing,communication systems,***(Gr),a leading two-dimensional material,has demonstrated significant potential for photodetection in recent ***,its relatively weak interaction with light poses challenges for practical *** integration of silicon(Si)and perovskite quantum dots(PQDs)has opened new avenues for Gr in the realm of next-generation *** review provides a comprehensive investigation of Gr/Si Schottky junction PDs and Gr/PQD hybrid PDs as well as their *** operating principles,design,fabrication,optimization strategies,and typical applications of these devices are studied and *** these discussions,we aim to illuminate the current challenges and offer insights into future directions in this rapidly evolving field.

关键词： quantum discussions summarized