Dos Orhun, Cavdar Sukru
Department of Advanced Technologies, Graduate School of Natural and Applied Sciences, Gazi University, Ankara 06530, Turkey.
Alparslan Defence Sciences and National Security Institute, National Defence University, Ankara 06530, Turkey.
ACS Omega. 2025 Apr 22;10(17):17875-17886. doi: 10.1021/acsomega.5c00708. eCollection 2025 May 6.
Spinel NiCoO is a promising material for electronic applications due to its tunable nanostructures and electrical properties. This study systematically investigates the effect of varying urea concentrations in the hydrothermal solution on the nanostructural evolution of NiCoO (NCO) and its impact on electrical and dielectric properties. By varying urea content, distinct morphologies-including nanosheets, nanoleaves, and nanofibers-were obtained and characterized via XRD, XPS, and FE-SEM analysis. To evaluate the electrical characteristics, capacitance and conductance measurements were performed using an LCR Meter at room temperature over a frequency range of 100 Hz to 1 MHz. The results revealed negative capacitance at low frequencies, linked to polarization changes and minority charge carriers. Also, dielectric parameters were calculated from measured values, showing that nanoform variations influence conductivity trends. This study provides new insights into how nanoform variations in NiCoO, controlled by synthesis parameters, influence its dielectric behavior. The findings significantly contribute to the understanding of negative capacitance and the tunability of electrical properties in NCO, highlighting their potential for future electronic and dielectric applications.
尖晶石型NiCoO因其可调控的纳米结构和电学性质，是一种很有前景的电子应用材料。本研究系统地研究了水热溶液中尿素浓度的变化对NiCoO（NCO）纳米结构演变及其对电学和介电性能的影响。通过改变尿素含量，获得了包括纳米片、纳米叶和纳米纤维在内的不同形貌，并通过XRD、XPS和FE-SEM分析对其进行了表征。为了评估电学特性，在室温下使用LCR测试仪在100 Hz至1 MHz的频率范围内进行了电容和电导测量。结果表明，在低频下存在负电容，这与极化变化和少数载流子有关。此外，根据测量值计算了介电参数，结果表明纳米形态的变化会影响电导率趋势。本研究为合成参数控制下的NiCoO纳米形态变化如何影响其介电行为提供了新的见解。这些发现对理解NCO中的负电容和电学性质的可调性有重要贡献，突出了它们在未来电子和介电应用中的潜力。
