Institutional Digital Repository (Indian Institute of Technology Kharagpu)

Thaker, Parth

DNS and LES of Compressible Turbulent Round Jets

Singh, Pankaj

Semantics and Coherence-based Efficient Query Expansion Techniques for Ad-hoc Retrieval

Dey, Nikita

Abstract
The thesis, titled “Nano-material-based Printed Micro-Supercapacitor”,
focuses on the urgent requirement for effective energy storage solutions in the
swiftly advancing electronic domain. Fossil fuels, which currently account for 68%
of energy use, are confronted with the issues of limited supplies and environmental
consequences. Therefore, it is imperative to investigate environmentally beneficial
alternatives. Although renewable sources are present, their sporadic availability
emphasizes the significance of having energy storage devices to provide on-demand
energy supply. Supercapacitors are becoming important competitors due to their
high power density, fast charge-discharge rates, lightweight design, and long lifes-
pan.Microscale energy storage is crucial in order to overcome the constraints of
traditional batteries and capacitors. Micro-Supercapacitors (MSCs) fill the need
by offering high power density, long-lasting cycle life, and fast charging capability.
Nevertheless, there are still areas of research that need to be addressed in order
to achieve scalable production, planar integration, flexible exploration, and the
identification of suitable electrode materials for MSCs.
The present study has undertaken a systematic exploration into the electro-
chemical potential and practical applications of nickel selenide compounds, with
a particular emphasis on Ni6Se5 and other stoichiometries within the nickel se-
lenide family. Initially, we investigate a novel one-step hydrothermal synthesis
technique utilized for the in-situ development of a binder-free Ni6Se5 electrode
on nickel foam. The electrochemical performance of the Ni6Se5/NF electrode has
been demonstrated to be exceptional, as evidenced by its sustained specific ca-
pacitance retention of 81% after 20,000 cycles and its high specific capacitance of
473.5 Fg−1at a current density of 4 Ag−1. Furthermore, the Ni6Se5/NF/AC ASC
device exhibits impressive energy density metrics, registering 97.3 Whkg−1, along-
side power densities of 2325 Wkg−1 and 7750 Wkg−1, even at an energy density of
71 Whkg−1. When utilized as an anode material in lithium-ion batteries, Ni6Se5
xv
manifests a noteworthy discharge capacity of 939.7 mAhg−1 at a current density
of 100 mAg−1, retaining 87% of its initial capacity after 30 cycles. Additionally,
three electrode materials derived from the nickel-selenide family are synthesized:
NiSe2, Ni3Se4, and NiSe. NiSe emerges as a standout option, demonstrating ex-
ceptional energy storage proficiency, attaining a specific capacity of 93.3 mAhg−1
at a current density of 12 Ag−1, and showcasing extraordinary cycling stability,
preserving 98% of its capacity over a prolonged 30,000 charge-discharge cycles.
Following that, we present screen printing as a material-compatible, scalable, and
economical fabrication method for in-plane NiSe-MSC construction. In order to
fabricate NiSe-MSC, the rheology of screen-printable NiSe active material ink was
optimized and then applied to a flexible PET substrate positioned atop a silver
current collector in the interdigitated electrode format design. Flexible symmet-
ric NiSe-MSC shows notable energy density (5.28 mW h cm−3) and power density
(822.86 mW cm−3). It has been determined that Nickel Selenide (NiSe) stores pos-
itive charge efficiently. Expanding upon this realization, attention is redirected
towards the production of an asymmetric micro-supercapacitor. The distinctive
configuration of this apparatus features a printed in-plane negative electrode made
of Ti3C2Tx-Mxene and a positive electrode made of NiSe active material. The
purpose of strategically incorporating these materials is to augment the energy
density, specifically for use in micro-supercapacitor applications. By virtue of this
distinctive configuration, energy density is augmented for micro-supercapacitor
uses; it exhibits a power density of 1285.7 mW cm−3 and an energy density of
117.6 mW h cm−3, both of which are achieved over an extended potential range of
0 to 1.8 V. The NiSe/MXene A-MSC outperforms symmetric alternatives, exhibit-
ing impressive volumetric specific capacity, energy density, and power density. Its
remarkable durability, retaining 72% of its initial capacitance after one thousand
charging cycles and 81% after 250 bending cycles, underscores its potential as a
flexible and enduring energy storage device.
This extensive investigation signifies a notable progress in the development of
effective and dependable energy storage methods. In addition to investigating elec-
trode materials, the discoveries provide practical options for micro-supercapacitors
and flexible energy storage systems. The applications range from wearable elec-
tronics to various industrial and environmental sectors, offering a future in which
cost-effective and environmentally friendly energy conversion and storage tech-
nologies are of great importance. The study also explores architectural alterations
designed to improve the performance of supercapacitors, with a focus on produc-
ing in-plane micro-supercapacitors (MSCs) via layer-by-layer screen printing. The
xvi
technique, renowned for its economical nature and ease of use, is especially ad-
vantageous when combined with a current collector positioned beneath the elec-
trode. Prior to the screen-printing process, ink rheology is carefully optimized,
recognizing the crucial influence of rheological properties on the performance of
supercapacitors, regardless of the specific active electrode material used.
Keywords: Supercapacitors, pseudocapacitors, nickel selenide, Mxene, flexi-
ble micro supercapacitor, micro-supercapacitors, screen printing, ink formulation.
xvii


Nano-material based Printed Micro-Supercapacitor

Shome, Anupam

Performance Analysis of Underlay Cooperative Cognitive Radio Network in Energy Harvesting Scenario

K.P., Surya

Preparation, Processing, and Properties of Natural Rubber Nanocomposites Using Carbon Black-Nanofiber Hybrid Fillers

Maji, Pabitra

Dynamic Analyses of Laminated and 3D Textile Composite Panels

Chandra, Neha

Production of Bioethanol and Other Value-Added Co-Products from a Marine Cyanobacterium Synechococcus Elongatus BDU 10144

Gupta, Bramha

Analysis and Modelling of Photocatalytic System Removing Pharmaceuticals 
from Wastewater 
2023 
 
xxiii 
 
ABSTRACT 
The occurrence of pharmaceuticals in the aqueous environment and their associated 
ecotoxicological effects raises global concern, which in turn promotes extensive research 
on pharmaceutical removal from wastewater. The present research stems from the 
necessity of the development of heterojunction photocatalysts and their subsequent 
application for photocatalytic degradation of pharmaceuticals from wastewater. An 
atomically thin sulfur-doped g-C3N4/ZnO (or SCZ) nanosheet was prepared using a facile 
synthesis method, and the major synthesis process parameters, viz. the S-C3N4 fraction for 
the zinc precursor and calcination temperature, were optimized targeting the ciprofloxacin 
removal. The multivariate optimization was performed through response surface 
methodology coupled with a face-centered central composite design. The characterization 
of the photocatalysts displayed that the variation of the process parameters has a significant 
impact on elemental composition, crystallinity, surface morphology, oxygen vacancies, 
and other physicochemical properties of the photocatalyst. The SCZ catalyst has been 
successful in ciprofloxacin removal and showed good energy efficiency, COD removal 
efficiency, and reusability. The presence of different ions and organics in water matrices 
and experimental conditions have significantly affected the ciprofloxacin removal. 
Superoxide radical was identified as the driving radical and was predominantly involved 
in ciprofloxacin degradation. The spent photocatalyst has also shown similar 
physicochemical properties as the pristine SCZ catalyst. Further, the powdered SCZ 
catalyst was immobilized on chitosan hydrogels (named SCZ-CH hydrogels), which 
facilitated their separation from the aqueous solution. SCZ-CH hydrogels also successfully 
degraded the ciprofloxacin from the wastewater. Pristine and used SCZ-CH hydrogels 
showed multifaceted physicochemical properties supporting their reactions with the 
ciprofloxacin molecules. SCZ-CH hydrogels also showed better energy efficiency, COD 
removal efficiency, and reusability. 
Considering the enhanced performance of the SCZ catalyst and SCZ-CH hydrogels, both 
catalysts were used to degrade diclofenac and tetracycline and achieved a high degree of 
removal. Both catalysts showed better energy efficiency, COD removal efficiency, and 
reusability. The degradation pathways of diclofenac and tetracycline using both catalysts 
Analysis and Modelling of Photocatalytic System Removing Pharmaceuticals 
from Wastewater 
2023 
 
xxiv 
 
were delineated, which showed their reaction mechanisms and transformed product 
formation. The removal of co-existing pharmaceuticals was also successfully assessed. 
Further, the continuous photocatalytic reactor was developed to treat the synthetic and real 
wastewater in continuous mode, which was further modified using a biological reactor to 
deal with the highly polluted real wastewater originating from pharmaceutical industries 
and households. The watering of the plants using treated wastewater and inductively 
coupled plasma-mass spectroscopy (ICP-MS) were also carried out to assess the toxicity 
of the treated effluent and stability of the catalyst, respectively, which showed no effects 
on the plants and the presence of acceptable amounts of trace metals, respectively. Hence, 
the proposed catalysts and the photocatalytic systems could be potential sustainable 
measures for the treatment of micropollutants and other pharmaceuticals from wastewater 
at the field scale. 
 
KEYWORDS: Advanced oxidation processes, Artificial neural network, Continuous and 
integrated photocatalytic systems, Degradation efficiency, Ecotoxicological effects,  
Heterojunction catalyst, Hydrogels, Immobilization, Industrial wastewater, Microscopy, 
Multivariate optimization, Pharmaceuticals, Photocatalysis, Sources and pathways, 
Spectroscopy, Sustainability, Toxicity analysis, Transformed products, Water matrices, 
Wastewater treatment 


Analysis and Modelling of Photocatalytic System Removing Pharmaceuticals from Wastewater

Khan, Anasua

A Study of Defects and Disorders on the Electronic, Magnetic, and Optical Properties of Certain Double-Perovskite Manganites

Singh, Rashika

Structural and Functional Characterization of Thiolase and Antigen Mtb8.4 from Mycobacterium Tuberculosis

Not a member yet