Article
Engineering, Environmental
Chuanhui Zhu, Hao Tian, Bin Huang, Guohong Cai, Chongyang Yuan, Yutian Zhang, Yinle Li, Guangqin Li, Hu Xu, Man-Rong Li
Summary: This study investigated a family of Ruddlesden-Popper iridate oxides with different dimensions of bulk crystal structure to understand their intrinsic activity on oxygen evolution reaction (OER). The results showed that these oxides, especially Sr3Ir2O7, displayed enhanced catalytic activity compared to IrO2, and the dimensionality of the bulk crystal structure played a key role in programming the optimum catalytic activity. Additionally, the decrease in dimensionality led to weakened adsorption of oxygen intermediates and accelerated kinetics, while elevated conductivity and optimized binding energy contributed to the exceptional OER activity of Sr3Ir2O7.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
Mohga. F. Mostafa, Shimaa. S. El-Khiyami, Ahmed K. Tammam
Summary: The powder X-ray diffraction and differential scanning calorimetric techniques were used to investigate the crystal structure, phase transitions, and conductivity properties of [NH3(CH2)(7)(NH3)]MnBr4 hybrid perovskite. The results show that proton conduction and bromide ion migration dominate the conductivity at different temperature ranges, and the frequency dependence of the conductivity follows a super-linear power law. The carrier binding energies also vary between different phases.
MATERIALS CHEMISTRY AND PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Zezhu Zeng, Chen Chen, Cunzhi Zhang, Qian Zhang, Yue Chen
Summary: By studying the lattice dynamics and thermal conductivity in perovskites, we discovered that Cs2PbI2Cl2 and Cs2SnI2Cl2 samples have extremely low thermal conductivities. The phonon frequency renormalization of the octahedral rotational soft modes in Cs2PbI2Cl2 plays a crucial role in the thermal transport properties. We also observed similar phonon behaviors in other layered inorganic perovskites.
Article
Chemistry, Physical
Qurat ul Ain, Sumera Siddique, Shahzad Akhtar Ali, Hasan Ahmed, Mohsin Khan, Murtaza Saleem, Habib Ur Rehman, Ata Ulhaq, Ammar A. Khan
Summary: This study compares the structural and optical properties of perovskites coated with two different materials. The results show that coating with a discotic liquid crystal, HAT5, improves the long-term stability of hybrid perovskites.
MOLECULAR SYSTEMS DESIGN & ENGINEERING
(2022)
Article
Materials Science, Ceramics
V. A. Dudnikov, Yu S. Orlov, L. A. Solovyov, S. N. Vereshchagin, S. Yu Gavrilkin
Summary: A new anion-deficient Sr2.4Dy0.6Co2O7-delta perovskite phase has been synthesized and characterized, showing specific crystal parameters and oxygen vacancy distribution. The compound exhibits stability under various atmospheres and reversible oxygen absorption/release at high temperatures. Additionally, magnetic properties and electrical conductivity changes have been investigated in detail.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Yixuan Shi, Zahra Sepahi, Leilane R. Macario, Cheryl Sturm, Nour Mashmoushi, Yaron Amouyal, Holger Kleinke
Summary: We studied the impact of varying amounts of CaO layers on the thermoelectric properties of the Ruddlesden-Popper series CaO(CaMnO3)(m) with m = 1, 2, 3, infinity. Dense pellets were obtained through extended ball-milling and hot-pressing, with the sample containing the most CaO layers (m = 1) exhibiting the lowest electrical and thermal conductivity and the highest Seebeck coefficient. Ultimately, the perovskite CaMnO3 (m = infinity) without CaO layers showed the best thermoelectric properties.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Chemistry, Physical
Hiroshi Yaguchi, Kotaro Fujii, Yoshinori Tsuchiya, Hiraku Ogino, Yoshihiro Tsujimoto, Masatomo Yashima
Summary: This study discovers RP oxychlorides Ba3Y2O5Cl2, Sr3Sc2O5Cl2, and Sr2ScO3Cl as a class of oxide-ion conductors. Ba3Y2O5Cl2 shows higher oxide-ion conductivity compared to Sr3Sc2O5Cl2, mainly attributed to its larger free and lattice volumes. The results suggest that RP oxychlorides are potential candidates for high oxide-ion conductivity.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Yihui Liu, Zhuofei Pan, Xiyong Chen, Chao Wang, Haizhao Li
Summary: A new type of Ruddlesden-Popper Pr1.2Sr0.8Ni1-xMoxO4+delta (PSNMO) cathode with different Mo doping levels was prepared using the sol-gel method. The maximum conductivity of Pr1.2Sr0.8NiO4+delta cathodes was achieved and then decreased with the continuous increase of Mo amount in all the Mo-doped cathodes. The Pr1.2Sr0.8Ni0.950Mo0.050O4+delta cathode showed the lowest polarization resistance among the PSNMO cathodes at 750 degrees C. Mo-doping improved the oxygen surface exchange properties of PSNMO cathodes, mainly due to the co-interaction of oxygen vacancy and interstitial oxygen in PSNO cathodes after Mo-doping.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Aleksandr Bamburov, Yevgeniy Naumovich, Dmitry D. Khalyavin, Aleksey A. Yaremchenko
Summary: This study investigated the possibility of introducing cation vacancies into the Ln sublattice of perovskite-related Ruddlesden-Popper nickelates. The results showed that the concentration of cation vacancies in the A sublattice of the Ruddlesden-Popper structure is very low, and the introduction of vacancies enhances the diffusivity of A-site cations and destabilizes the structure. However, the nominal cation deficiency has no effect on the electrical conductivity and oxygen permeability of the ceramics.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Shuai Zhao, Cui Chen, Huan Li, Wenrui Zhang
Summary: By using first-principles calculations, the migration mechanism of alkali ions in RP antiperovskites was investigated, showing that alkali interstitials have lower migration barriers than vacancies and play a crucial role in improving the ionic conductivity.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Physical
Haiqiang Chen, Yutian Lei, Huanhuan Yao, Zhizai Li, Guoqiang Peng, Xufeng Zhou, Haoxu Wang, Qian Wang, Zhiwen Jin
Summary: This study investigates the influence of a binary mixed solvent on the film quality and photovoltaic properties of (PEA)(2)Cs4Pb5I16 (n = 5). It is found that the crystallization rate and crystal growth can be controlled by adjusting the amount of dimethyl sulfoxide (DMSO), leading to improved device performance.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Shu-Fang Li, Bao-Qin Zhang, Ya-Nan Li, Dong Yan
Summary: Anion doping engineering was used to improve the oxygen evolution performance of Ruddlesden-Popper-type perovskite SrLaCoO4. Developing efficient and durable oxygen evolution catalysts is crucial for sustainable energy conversion and storage. The Cl anion-doped perovskite oxides, SrLaCoO4-x Cl x (SLCOCl x ), were found to be highly efficient OER catalysts, with SLCOCl0.15 demonstrating significantly enhanced OER activity due to the tuning of electronic structure and generation of oxygen vacancies.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Nicolas Zapp, Florian Oehler, Marko Bertmer, Henry Auer, Denis Sheptyakov, Clemens Ritter, Holger Kohlmann
Summary: Dark-brown heteroanionic hydrides of LiLa2N1.5H2.5 and LiLa2N0.84(6)H1.56(3)O1.16(6) were synthesized by solid-state reactions, crystallizing in K2NiF4 type structure with mixed H/N and N/O sites respectively. The latter is a semiconductor with small band gap and partly covalent Li-H interaction.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Preetha Chandrasekharan Meenu, Pralok K. Samanta, Takefumi Yoshida, Niall J. English, Santanu Prasad Datta, Satyapaul A. Singh, Srikanta Dinda, Chanchal Chakraborty, Sounak Roy
Summary: The study demonstrates that optimal doping of Sr2+ in La1.4Sr0.6NiO4+delta leads to the highest reactivity for methanol oxidation, with a lattice oxygen-mediated reaction mechanism facilitating the process.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Xinwei Zhao, Ting Zheng, Weiwei Zhao, Yuanfang Yu, Wenhui Wang, Zhenhua Ni
Summary: By varying the composition ratio of organic bulky spacer cations 1-naphthylmethylamine (NMA) and phenylethyl-ammonium (PEA), the phase distribution of Ruddlesden-Popper Perovskite (RPP) is regulated, resulting in improved photoluminescence (PL) emission and expanded application in optical devices.
Article
Physics, Applied
Rajni Bansal, Gurudeo Nirala, Akash Kumar, Sujeet Chaudhary, P. K. Muduli
Article
Energy & Fuels
Vishnu Vijaykumar, Gurudeo Nirala, Dharmendra Yadav, Upendra Kumar, Shail Upadhyay
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2020)
Article
Physics, Multidisciplinary
Gurudeo Nirala, Dharmendra Yadav, Shail Upadhyay
Summary: The oxide Sr2MnO4 was synthesized using the solid-state reaction technique, and its purity and structure were verified through FTIR and XRD analysis. The band gap was calculated to be 1.15 eV, and XPS analysis revealed the presence of Mn3+ and Mn4+ valence states. AC electrical conductivity measurements at different temperatures and frequencies showed a change in the conduction mechanism.
Article
Materials Science, Multidisciplinary
Dharmendra Yadav, Gurudeo Nirala, Sushma Yadav, Upendra Kumar, Shail Upadhyay, Satyam Kumar
Summary: Samples of the system SrCe1-xGdxO3 (x = 0.0, 0.02, 0.04, 0.06, and 0.10) were prepared and investigated for their structure, properties, and conductivity, showing potential as mixed ionic and electronic conductors for SOFCs. The incorporation of Gd into the lattice reduced the optical bandgap and grain size, with the highest conductivity observed for SrCe0.98Gd0.02O3 at 600 degrees C. XPS spectra confirmed the presence of Ce in different states and oxygen vacancies, which were further analyzed using Raman spectroscopy.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2021)
Article
Materials Science, Ceramics
Gurudeo Nirala, Dharmendra Yadav, Tarun Katheriya, Shail Upadhyay
Summary: Several compositions of Sr2Mn1-xSnxO4 system were synthesized using solid-state ceramic method in air. A change in the sign of the permittivity above a specific temperature was observed at all frequencies, and it was found that this negative permittivity was caused by plasma oscillations of thermally excited free charge carriers. XPS analysis confirmed mixed-valence states of Mn (Mn4+ and Mn3+) and Sn (Sn4+ and Sn2+) ions, while UV-vis.-IR spectroscopy results indicated the generation of defect states in the forbidden bandgap region of Sr2MnO4 on Sn substitution at Mn site. These synthesized samples show promise as metamaterials for applications in the radio frequency (10 Hz-2 MHz) region due to their high-temperature plasmonic behavior.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Gurudeo Nirala, Tarun Katheriya, Dharmendra Yadav, Shukdev Pandey, Shail Upadhyay
Summary: The solid-state ceramic method was used to synthesize Sr2Mn1-xNbxO4 compounds, and impurities were found in certain compositions. The permittivity and AC conductivity experiments showed different behaviors at different temperatures, possibly due to plasmonic oscillations of charge carriers. This indicates the potential of the Sr2Mn1-xNbxO4 system for switching action.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Gurudeo Nirala, Tarun Katheriya, Dharmendra Yadav, Harish Verma, Shail Upadhyay
Summary: The powder and ceramics of La-substituted layered oxides LaxSr2-xMn1-xO4 were synthesised using solid-state reaction technique. The synthesized compositions exhibited coil-less inductive characteristics, indicating their potential as coil-less inductors.
EMERGENT MATERIALS
(2023)
Proceedings Paper
Physics, Condensed Matter
Upendra Kumar, Dharmendra Yadav, Gurudeo Nirala, Shail Upadhyay, Epsita Kar, Manish Kumar Srivastava
DAE SOLID STATE PHYSICS SYMPOSIUM 2019
(2020)
