Gitana Valeckytė

Ms. Gitana Valeckytė

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 September 2024 in Materials
Verified
Journal Article
Open access
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Zita SukackieneZita Sukackiene
Zita Sukackiene
GVGitana Valeckytė
Gitana Valeckytė
Virginija KepenieneVirginija Kepeniene
Virginija Kepeniene
ISIrena Stalnionienė
Irena Stalnionienė
VJVitalija Jasulaitienė
Vitalija Jasulaitienė
ENEUGENIJUS NORKUS
EUGENIJUS NORKUS
The production of high-purity hydrogen from hydrogen storage materials with further direct use of generated hydrogen in fuel cells is still a relevant research field. For this purpose, nickel-molybdenum-plated copper catalysts (NiMo/Cu), comprising between 1 and 20 wt.% molybdenum, as catalytic materials for hydrogen generation, were prepared using a low-cost, straightforward electroless metal deposition method by using citrate plating baths containing Ni2+–Mo6+ ions as a metal source and morpholine borane as a reducing agent. The catalytic activity of the prepared NiMo/Cu catalysts toward alkaline sodium borohydride (NaBH4) hydrolysis increased with the increase in the content of molybdenum present in the catalysts. The hydrogen generation rate of 6.48 L min−1 gcat−1 was achieved by employing NiMo/Cu comprising 20 wt.% at a temperature of 343 K and a calculated activation energy of 60.49 kJ mol−1 with remarkable stability, retaining 94% of its initial catalytic activity for NaBH4 hydrolysis following the completion of the fifth cycle. The synergetic effect between nickel and molybdenum, in addition to the formation of solid-state solutions between metals, promoted the hydrogen generation reaction.

7 October 2023 in Coatings
Verified
Journal Article
Open access
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Zita SukackieneZita Sukackiene
Zita Sukackiene
GVGitana Valeckytė
Gitana Valeckytė
Virginija KepenieneVirginija Kepeniene
Virginija Kepeniene
ISIrena Stalnionienė
Irena Stalnionienė
VJVitalija Jasulaitienė
Vitalija Jasulaitienė
ENEUGENIJUS NORKUS
EUGENIJUS NORKUS
In this paper, the generation of hydrogen from alkaline sodium borohydride solution by hydrolysis is studied. To obtain catalysts for efficient hydrogen generation, Ni, Mn, Mo, and Co metals were deposited on the Cu surface by the simple electroless metal deposition method using morpholine borane as a reducing agent. Depending on the peculiarities of the deposition of each metal, the coating thickness was ca. 1 μm for all catalysts. The deposited coatings were compact and crack-free, with multilayer characteristics and a cauliflower-like structure. The prepared Ni/Cu, NiMn/Cu, NiMo/Cu, NiCo/Cu, NiCoMn/Cu, NiCoMo/Cu, and NiCoMoMn/Cu catalysts showed an efficient catalytic activity for sodium borohydride hydrolysis reaction. The lowest activation energy of 45.3 kJ mol−1 for sodium borohydride hydrolysis reaction was obtained using the NiCoMoMn/Cu catalyst. The highest hydrogen generation rate of 3.08 mL min−1 was also achieved using this catalyst at 303 K. With a further increase in temperature to 343 K, the hydrogen generation rate catalyzed by the NiCoMoMn/Cu increased 7.7 times and reached 23.57 mL min−1.

15 August 2025 in Electrochem
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Journal Article
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RŠRaminta Šakickaitė
Raminta Šakickaitė
Zita SukackieneZita Sukackiene
Zita Sukackiene
Virginija KepenieneVirginija Kepeniene
Virginija Kepeniene
Aldona BalčiūnaitėAldona Balčiūnaitė
Aldona Balčiūnaitė
RSRaminta Stagniūnaitė
Raminta Stagniūnaitė
Loreta Tamasauskaite-TamasiunaiteLoreta Tamasauskaite-Tamasiunaite
Loreta Tamasauskaite-Tamasiunaite
In this study, ternary NiFeP coatings were fabricated on a copper substrate using a simple, fast, and cost-effective electroless deposition method. The coatings were named Ni85Fe4P12, Ni80Fe8P12, and Ni75Fe12P12, indicating 4, 8, and 12 at % of Fe, respectively. The surface morphology and composition of the coatings were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The activity of the prepared coatings was evaluated using the water-splitting reaction to determine the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in a 1 M KOH electrolyte solution. Electrochemical measurements were carried out in a temperature range from 25 °C to 55 °C. The HER and OER current density values increased by up to 2.58 and 2.13 times, respectively, with temperature increase compared to the result at 25 °C. All three coatings demonstrated activity in both reactions. Ni85Fe4P12 exhibited the highest catalytic efficiency in the HER, with the overpotential of 340 mV at 10 mAcm−2 and a Tafel slope of 61 mVdec−1. In the OER, the efficiency of the NiFeP catalysts correlated with their Fe content. The overpotential was 412 mV for Ni80Fe8P12 and 432 mV for Ni75Fe12P12 at 10 mAcm−2 with Tafel slopes of 96 and 91 mVdec−1, respectively. This study underscores the critical influence of Fe content on the catalytic efficiency of NiFeP coatings, with reduced Fe content enhancing HER and increased Fe content benefits OER.

25 February 2026 in Materials
Verified
Journal Article
Open access
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GVGitana Valeckytė
Gitana Valeckytė
Zita SukackieneZita Sukackiene
Zita Sukackiene
Virginija KepenieneVirginija Kepeniene
Virginija Kepeniene
RŠRaminta Šakickaitė
Raminta Šakickaitė
JVJūratė Vaičiūnienė
Jūratė Vaičiūnienė
ENEUGENIJUS NORKUS
EUGENIJUS NORKUS
The generation of high-purity hydrogen via chemical reaction from hydrogen-rich materials is one of the ways in the alternative energy industry. In this approach, the utilization of catalytic materials that possess the capacity to initiate the decomposition of the starting material and the subsequent release of hydrogen is of paramount importance. In this study, nickel/cobalt-plated copper catalysts (NiCo/Cu) are presented, comprising from 4 to 90 wt.% of cobalt as catalytic materials for hydrogen generation via sodium borohydride (NaBH4) hydrolysis reaction. The NiCo/Cu catalysts were synthesized via electroless deposition from glycine-based baths, utilizing Ni2+ and Co2+ ions as metal sources and morpholine borane (MB) as the reducing compound. The catalytic performance in alkaline NaBH4 hydrolysis was found to correlate with the cobalt loading in the coating. The maximum rate of hydrogen production, which was determined to be 14.22 L min−1 gcat−1, was achieved at 343 K for a catalyst composed of 90 wt.% Co. The reaction proceeded with the activation energy of 52.5 kJ mol−1, while the catalyst exhibited high durability, preserving nearly 88% of its initial activity after five successive reaction cycles. The combination of nickel and cobalt, along with their synergistic effect and high efficiency in the borohydride hydrolysis reaction, makes them promising catalysts.


25 June 2026 in Coatings
Verified
Journal Article
Open access
PDF file
GVGitana Valeckytė
Gitana Valeckytė
Zita SukackieneZita Sukackiene
Zita Sukackiene
Virginija KepenieneVirginija Kepeniene
Virginija Kepeniene
RSRaminta Stagniūnaitė
Raminta Stagniūnaitė
LŠLukas Šimkus
Lukas Šimkus
ENEUGENIJUS NORKUS
EUGENIJUS NORKUS
The production of high-purity hydrogen from chemical hydrogen storage materials such as sodium borohydride (NaBH4) has been identified as a particularly promising candidate due to its high hydrogen storage capacity and environmentally benign hydrolysis products. The incorporation of tungsten (W), thereby developing W-promoted NiMo catalytic systems, results in the enhance activity toward NaBH4 hydrolysis, thereby developing ternary NiMoW catalytic systems. The synthesis of NiMoW-coated copper catalysts (NiMoW/Cu) containing 3–11 wt.% of W was accomplished using a cost-effective and efficient electroless deposition method from citrate-based plating baths containing Ni2+, Mo6+, and W6+ ions. Morpholine borane was utilized as the reducing agent in this process. The catalytic activity of the prepared coatings toward alkaline NaBH4 hydrolysis increased as the tungsten content decreased within the investigated range of 3–11 wt.%. The highest hydrogen generation rate, reaching 9.87 L min−1 gcat−1, was achieved using the NiMoW/Cu catalyst containing 3 wt.% of W at 343 K. The corresponding apparent activation energy was calculated to be 52 kJ mol−1. In addition, the catalyst demonstrated notable 89.1% stability, maintaining a high degree of catalytic activity after undergoing five successive hydrolysis cycles. The enhanced catalytic performance was attributed to synergistic interactions between Ni, Mo, and W and to the favorable surface morphology of the multicomponent coating, which promoted the hydrogen generation reaction.