Improving Ni(OH)2 electrocatalysis with graphene quantum dots

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F26%3A0200773" target="_blank" >RIV/00216305:26620/26:0200773 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0360319925058768?getft_integrator=clarivate&pes=vor&utm_source=clarivate" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0360319925058768?getft_integrator=clarivate&pes=vor&utm_source=clarivate</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijhydene.2025.152873" target="_blank" >10.1016/j.ijhydene.2025.152873</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Improving Ni(OH)2 electrocatalysis with graphene quantum dots

Popis výsledku v původním jazyce

Water splitting is a critical process for sustainable energy transition, involving the electrolysis of water into its constituent elements, hydrogen and oxygen. In this study, we demonstrate the superior electrocatalytic activity of graphene quantum dots (GQDs)-decorated nickel hydroxide (Ni(OH)2) nanostructures for the oxygen evolution reaction (OER) in alkaline media. Ni(OH)2 nanowalls are synthesized on graphene paper substrates by chemical bath deposition (CBD) and uniformly decorated with GQDs. Precise optimization of the GQDs amount indicates that a low number of GQDs offers limited improvement of the OER, while a high number is unfavorable due to the minor exposed surface of the electrocatalyst. Instead, an intermediate quantity of GQDs significantly enhances the OER performance metrics, leading to a low overpotential at 10 mA cm-2 current density ((10) of 308 mV and a Tafel slope of 53 mV dec-1, rapid electron transfer, high turnover frequency (TOF) of 5.5 x 10-2 s-1 at 350 mV overpotential, large electrochemically active surface area (ESCA) of 145 cm2, good durability, and good cycling stability in 1 M KOH electrolyte (pH 14). Mott-Schottky analysis sheds light on the OER mechanism, revealing the role of GQDs in increasing the surface hole density of Ni(OH)2, thereby boosting the OER efficiency.

Název v anglickém jazyce

Improving Ni(OH)2 electrocatalysis with graphene quantum dots

Popis výsledku anglicky

Water splitting is a critical process for sustainable energy transition, involving the electrolysis of water into its constituent elements, hydrogen and oxygen. In this study, we demonstrate the superior electrocatalytic activity of graphene quantum dots (GQDs)-decorated nickel hydroxide (Ni(OH)2) nanostructures for the oxygen evolution reaction (OER) in alkaline media. Ni(OH)2 nanowalls are synthesized on graphene paper substrates by chemical bath deposition (CBD) and uniformly decorated with GQDs. Precise optimization of the GQDs amount indicates that a low number of GQDs offers limited improvement of the OER, while a high number is unfavorable due to the minor exposed surface of the electrocatalyst. Instead, an intermediate quantity of GQDs significantly enhances the OER performance metrics, leading to a low overpotential at 10 mA cm-2 current density ((10) of 308 mV and a Tafel slope of 53 mV dec-1, rapid electron transfer, high turnover frequency (TOF) of 5.5 x 10-2 s-1 at 350 mV overpotential, large electrochemically active surface area (ESCA) of 145 cm2, good durability, and good cycling stability in 1 M KOH electrolyte (pH 14). Mott-Schottky analysis sheds light on the OER mechanism, revealing the role of GQDs in increasing the surface hole density of Ni(OH)2, thereby boosting the OER efficiency.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

21000 - Nano-technology

Projekt

—

Návaznosti

O - Projekt operacniho programu

Rok uplatnění

2026

Kód důvěrnosti údajů

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

Název periodika

International journal of hydrogen energy

ISSN

0360-3199

e-ISSN

1879-3487

Svazek periodika

199

Číslo periodika v rámci svazku

Leden

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

14

Strana od-do

—

Kód UT WoS článku

001637189500001

EID výsledku v databázi Scopus

2-s2.0-105023829608