Expansion of the multifunctionality in off-stoichiometric manganites using post-annealing and high pressure: physical and electrochemical studies

Gong, Zhiwei1; Xu, Wei2; Liedienov, N. A.1,3; Butenko, D. S.4; Zatovsky, I., V5,6; Gural'skiy, I. A.7; Wei, Ziyu8; Li, Quanjun1; Liu, Bingbing1; Batman, Yu A.9; Pashchenko, A., V1,3,10; Levchenko, G. G.1,3

2022-08-01

10.1039/d2cp01959k

PHYSICAL CHEMISTRY CHEMICAL PHYSICS   Impact Factor & Quartile

1463-9076

1463-9084

Prospects for the use of manganites in various areas of modern technologies require comprehensive studies of their physical and chemical properties. La0.9Mn1.1O3 (LMO) ceramics have been synthesized at an annealing temperature t(ann) of 1150 degrees C with further post-annealing at 1250, 1350, and 1450 degrees C. As t(ann) increases, the structure symmetry changes, and both the crystallite size and chemical defects increase. The post-annealing, on one hand, leads to a dramatic reduction of the magnetocaloric effect (MCE) |-Delta Smax(M)| from 3.50 to 0.75 J (kg K)(-1) at 2 T and a Curie temperature T-C from 227 to 113 K with increasing t(ann). On the other hand, an external hydrostatic high-pressure P works oppositely enhancing ferromagnetic interactions. The saturation of -Delta Smax(M) and T-C is already achieved at a relatively low P of approximate to 0.4 GPa. LMO-1150 exhibits the best magnetocaloric characteristics compared with other studied samples. Moreover, the electrochemical characteristics of the LMO materials as electrocatalysts for overall water splitting (OER process) and features of their transformation in different 0.5 M K2SO4, 0.5 M K2HPO4, and 0.1 M K2B4O7 electrolytes have been studied thoroughly. After electrocatalysis of LMO, the magnetization M decreases and T-C remains, which makes it possible to control the depletion of electrodes and predict their working time based on the magnetic measurements. All samples show the best OER activity in the 0.5 M K2HPO4 media. The obtained results demonstrate the ways for controlling the MCE of LMO under changing internal and external conditions, and an evaluation of the possibilities for their OER applications in electrocatalysts.

SCI

English

Others

National Key Research and Development Program of China[2018YFA0305900] ; National Natural Science Foundation of China["11874172","U2032215","11634004"]

Chemistry ; Physics

Chemistry, Physical ; Physics, Atomic, Molecular & Chemical

WOS:000850182200001

ROYAL SOC CHEMISTRY

CHEMISTRY

Web of Science

1.Jilin Univ, Int Ctr Future Sci, State Key Lab Superhard Mat, Changchun 130012, Peoples R China
2.Jilin Univ, Coll Chem, State Key Lab Inorgan Synth & Preparat Chem, Changchun 130012, Peoples R China
3.NASU, Donetsk Inst Phys & Engn, UA-03028 Kiev, Ukraine
4.Southern Univ Sci & Technol, Acad Adv Interdisciplinary Studies, Shenzhen 518055, Peoples R China
5.Jilin Univ, Coll Phys, Changchun 130012, Peoples R China
6.NASU, FD Ovcharenko Inst Biocolloidal Chem, UA-03142 Kiev, Ukraine
7.Taras Shevchenko Natl Univ Kyiv, UA-01601 Kiev, Ukraine
8.Heilongjiang Univ, Coll Phys Sci & Technol, Harbin 150080, Peoples R China
9.Bogomolets Natl Med Univ, UA-01601 Kiev, Ukraine
10.Inst Magnetism NASU & MESU, UA-03142 Kiev, Ukraine

Gong, Zhiwei,Xu, Wei,Liedienov, N. A.,et al. Expansion of the multifunctionality in off-stoichiometric manganites using post-annealing and high pressure: physical and electrochemical studies[J]. PHYSICAL CHEMISTRY CHEMICAL PHYSICS,2022.

Gong, Zhiwei.,Xu, Wei.,Liedienov, N. A..,Butenko, D. S..,Zatovsky, I., V.,...&Levchenko, G. G..(2022).Expansion of the multifunctionality in off-stoichiometric manganites using post-annealing and high pressure: physical and electrochemical studies.PHYSICAL CHEMISTRY CHEMICAL PHYSICS.

Gong, Zhiwei,et al."Expansion of the multifunctionality in off-stoichiometric manganites using post-annealing and high pressure: physical and electrochemical studies".PHYSICAL CHEMISTRY CHEMICAL PHYSICS (2022).