Sub-millimetre scale Van der Waals single-crystal MoTe2 for potassium storage: Electrochemical properties, and its failure and structure evolution mechanisms

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F21%3A43922175" target="_blank" >RIV/60461373:22310/21:43922175 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22810/21:43922175

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S2405829721004220" target="_blank" >https://www.sciencedirect.com/science/article/pii/S2405829721004220</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ensm.2021.09.006" target="_blank" >10.1016/j.ensm.2021.09.006</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Sub-millimetre scale Van der Waals single-crystal MoTe2 for potassium storage: Electrochemical properties, and its failure and structure evolution mechanisms

Popis výsledku v původním jazyce

Potassium-ion batteries (KIBs) are competent candidates for next-generation energy-storage systems due to the source abundance, cost efficiency, and high energy density from comparable electrode potential to lithium. However, developing practical electrode materials for KIBs is still in its infancy, and the electrochemical reaction mechanisms for a specific material are far from clear. Here, MoTe2, due to the merits of sizeable ion-intercalation interlayer spacing of Van der Waals-type material, superior electron conductivity of its metal-semimetal characteristics to wildly studied MoS2, was for the first time investigated as the working electrode for potassium storage. The potassiation/depotassiation mechanisms were unravelled, combining electrochemical analysis, ex-situ scanning electron microscope (SEM), ex-situ transmission electron microscope (TEM) and in-situ X-ray diffraction. Sub-millimetre single-crystal MoTe2 displayed a high volumetric capacity of 792.4 mAh cm(-3) h g(-1) at 100 mA g(-1). It decayed rapidly after 25 cycles caused by the deactivation of active electrode material from the irreversible crystalline cracking and structure evolution during the electrochemical cycling. At initial potassiation, 2H-MoTe2 was irreversibly converted to 1T-MoTe2 and then further converted to potassium telluride. And at initial depotassiation over 2.5 V (vs. K/K+), a tentative K-Mo-Te compound with R-3H Cs4Mo18Te20 structure was formed and soon irreversibly converted to K2Te3 under following potassiation. Meanwhile, the stepwise reversible conversion of K2Te3-KTeK5Te3 predominates the continuous electrochemical processes after the initial discharge/charge. Apart from the potential application for potassium-ion batteries, the conversion mechanisms amongst potassium tellurides also provide instructions for upcoming potassium-tellurium batteries.

Název v anglickém jazyce

Sub-millimetre scale Van der Waals single-crystal MoTe2 for potassium storage: Electrochemical properties, and its failure and structure evolution mechanisms

Popis výsledku anglicky

Potassium-ion batteries (KIBs) are competent candidates for next-generation energy-storage systems due to the source abundance, cost efficiency, and high energy density from comparable electrode potential to lithium. However, developing practical electrode materials for KIBs is still in its infancy, and the electrochemical reaction mechanisms for a specific material are far from clear. Here, MoTe2, due to the merits of sizeable ion-intercalation interlayer spacing of Van der Waals-type material, superior electron conductivity of its metal-semimetal characteristics to wildly studied MoS2, was for the first time investigated as the working electrode for potassium storage. The potassiation/depotassiation mechanisms were unravelled, combining electrochemical analysis, ex-situ scanning electron microscope (SEM), ex-situ transmission electron microscope (TEM) and in-situ X-ray diffraction. Sub-millimetre single-crystal MoTe2 displayed a high volumetric capacity of 792.4 mAh cm(-3) h g(-1) at 100 mA g(-1). It decayed rapidly after 25 cycles caused by the deactivation of active electrode material from the irreversible crystalline cracking and structure evolution during the electrochemical cycling. At initial potassiation, 2H-MoTe2 was irreversibly converted to 1T-MoTe2 and then further converted to potassium telluride. And at initial depotassiation over 2.5 V (vs. K/K+), a tentative K-Mo-Te compound with R-3H Cs4Mo18Te20 structure was formed and soon irreversibly converted to K2Te3 under following potassiation. Meanwhile, the stepwise reversible conversion of K2Te3-KTeK5Te3 predominates the continuous electrochemical processes after the initial discharge/charge. Apart from the potential application for potassium-ion batteries, the conversion mechanisms amongst potassium tellurides also provide instructions for upcoming potassium-tellurium batteries.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Projekt

<a href="/cs/project/GC20-16124J" target="_blank" >GC20-16124J: Dvojdimenzionální vrstevnaté dichalkogenidy přechodných kovů / nanostrukturované uhlíkové kompozity pro aplikace na elektrochemické uchovávání energie</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Energy Storage Materials

ISSN

2405-8297

e-ISSN

2405-8297

Svazek periodika

43

Číslo periodika v rámci svazku

DEC 2021

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

9

Strana od-do

284-292

Kód UT WoS článku

000703863600010

EID výsledku v databázi Scopus

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