Okenwa Okoli

Dr. Okenwa Okoli

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

View All Publications
Verified
Journal Article
Open access
PDF file
OEOkunzuwa Austine Ekuase
Okunzuwa Austine Ekuase
NANafiza Anjum
Nafiza Anjum
VEVincent Obiozo Eze
Vincent Obiozo Eze
OOOkenwa Okoli
Okenwa Okoli
Composite materials have gained increased usage due to their unique characteristic of a high-stiffness-to-weight ratio. High-performing composite materials are produced in the autoclave by applying elevated pressure and temperature. However, the process is characterized by numerous disadvantages, such as long cycle time, massive investment, costly tooling, and excessive energy consumption. As a result, composite manufacturers seek a cheap alternative to reduce cost and increase productivity. The out-of-autoclave (OoA) process manufactures composites by applying vacuum, pressure, and heat outside of the autoclave. This review discusses the common out-of-autoclave processes for various applications. The theoretical and practical merits and demerits are presented, and areas for future research are discussed.

Verified
Journal Article
Open access
PDF file
NANafiza Anjum
Nafiza Anjum
ANAbdullah Al Noman
Abdullah Al Noman
MRMd Mostafizur Rahman
Md Mostafizur Rahman
DSDebashis Sen
Debashis Sen
RLRobert A. Lazenby
Robert A. Lazenby
OOOkenwa Okoli
Okenwa Okoli
This study investigates the electrochemical behavior of Ti3C2Tx MXene for supercapacitor applications, focusing on its charge storage mechanisms using Electrochemical Impedance Spectroscopy (EIS). A novel equivalent circuit (EC) model, incorporating a diffusion layer resistance and a constant phase element, was developed to represent the impedance spectra, achieving a low error margin of 4.6%. The cycling stability of MXenes and charge storage parameters were evaluated using the developed EC model. This study demonstrated that the irreversible anodic oxidation of MXene begins around 0.3 V due to water molecule attack from the aqueous electrolyte, resulting in the formation of a titanium oxide layer that increases charge transfer resistance and impairs charge storage. It was further revealed that the cycling stability of MXene is also related to the oxidation of MXene, and the initial capacitance of 493 F/g at 100 mV/s is reduced by 27.5% after 1000 cycles. The contribution of charge storage factors was analyzed, with 85% of MXene’s capacitance found to be surface controlled. This research offers a deeper understanding of MXene’s charge storage mechanisms, providing critical insights into optimizing its electrochemical performance and stability. By establishing advanced modeling approaches and addressing challenges related to oxidation and resistance, this work enhances MXene’s potential for high-power supercapacitors in electromechanical actuator applications.

20 May 2014 in Advanced Materials Interfaces
Verified
Journal Article
Closed access
PDF file
JYJin Yan
Jin Yan
MUM. Jasim Uddin
M. Jasim Uddin
TDTarik J. Dickens
Tarik J. Dickens
DDDeborah E. Daramola
Deborah E. Daramola
OOOkenwa Okoli
Okenwa Okoli

4 August 2020 in The Journal of Physical Chemistry C
Verified
Journal Article
Closed access
VEVincent Obiozo Eze
Vincent Obiozo Eze
GAGeoffrey Ryan Adams
Geoffrey Ryan Adams
LCLucas Braga Carani
Lucas Braga Carani
RSRyan James Simpson
Ryan James Simpson
OOOkenwa Okoli
Okenwa Okoli

17 June 2020 in ACS Applied Nano Materials
Verified
Journal Article
Closed access
ASAbu S. Shohag
Abu S. Shohag
VEVincent O. Eze
Vincent O. Eze
LCLucas Braga Carani
Lucas Braga Carani
OOOkenwa Okoli
Okenwa Okoli

30 September 2014 in Physica Status Solidi (RRL) – Rapid Research Letters
Verified
Journal Article
Closed access
PDF file
MUMohammed J. Uddin
Mohammed J. Uddin
DDDeborah E. Daramola
Deborah E. Daramola
EVEver Velasquez
Ever Velasquez
TDTarik J. Dickens
Tarik J. Dickens
JYJin Yan
Jin Yan
OOOkenwa Okoli
Okenwa Okoli