Chemistry Commons^™

Synthesizing Viscoelasticity: Living Polymers, Micro-Macro Relations, And Paths For Resolution, Adam M. Hasler

Graduate Masters Theses

This thesis investigates the relationship between macroscopic rheological signals and underlying microscopic dynamics in complex fluids, specifically focusing on ”living polymers” within the cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal) surfactant system. The research addresses the inverse parameterization problem, demonstrating how bulk measurements like zero-shear viscosity can mask fundamentally different physical topologies, such as purely cylindrical, reptating micelles versus highly branched networks. Through the successful synthesis of viscoelastically ”degenerate” samples, the study utilizes an array of characterization techniques including frequency sweeps, Large Amplitude Oscillatory Shear (LAOS) to resolve these unique underlying states. Furthermore, the work explores further avenues of study …

Electrolyte Development And Interfacial Reactions At Multivalent Metal Anode For Next Generation Energy Storage Systems, Leslie Gates

Graduate Masters Theses

The increasing demand for safe, sustainable, and high-performance energy storage systems has driven significant interest in multivalent-ion batteries, including aluminum, magnesium, and zinc-based systems. These technologies have attracted attention due to their high theoretical energy densities, natural abundance, low cost, and environmentally benign nature. However, their development remains hindered by a limited fundamental understanding of electrolyte development and interfacial processes at the electrode–electrolyte interface, where complex electrochemical interactions govern battery performance and stability.

This thesis investigates electrode–electrolyte interactions in both a novel aluminum electrolyte and divalent magnesium and zinc systems. Beginning with the development and characterization of a novel aluminum …

In Situ Electrochemical Characterization Techniques For Active Hydrogen In Electrocatalytic Nitrate Reduction To Ammonia, Hong-Mei Li, Mei Yi, Zhao-Yu Jin, Ming-Hao Xie, Khalid M. Omer, Yong Guo, Pan-Pan Li

Journal of Electrochemistry

Electrocatalytic nitrate reduction to ammonia (NitRR) represents a sustainable pathway that integrates environmental remediation with the production of high-value ammonia. However, the activity and selectivity of this process are limited by the generation, consumption, and dynamic equilibrium of the key transient intermediate—active hydrogen (*H). Precise modulation of *H necessitates a comprehensive understanding of its behavior, which relies fundamentally on advanced in situ electrochemical characterization techniques. However, a systematic review dedicated to the rational selection and application of in situ electrochemical techniques for the specific characterization of *H in NitRR, with clear definitions of each technique's "detectable targets, quantitative accuracy, and …

Microwave-Assisted Synthesis Of Core-Shell Structured Pd@Pdptcufe Recessed Truncated Octahedral Nanocrystals For Multifunctional Electrocatalysis, De-Zhong Hu, Wen-Dan Jiang, Wei Keat Ng, Jun Yang, Xiong-Wu Kang

Journal of Electrochemistry

Developing cost-efficient and durable multifunctional electrocatalysts of hydrogen evolution reaction, oxygen reduction reaction and oxygen evolution reaction is crucial for improving energy conversion efficiency in electrolytic water splitting electrolyzer and advancing rechargeable zinc-air batteries. Polyhedral shaped nanocrystals with well-defined crystal facets represent a type of model catalysts that enables the exploration of structure-activity relationships. However, it is still very challenging to prepare alloy nanocrystals with multiple metal components due to their complicated redox potentials and mixing enthalpy. Herein, we report a rapid microwave-assisted polyol reduction method for syntheses of core-shell Pd@PdPtCu, Pd@PdPtCuNi, Pd@PdPtCuCo and Pd@PdPtCuZn octahedral nanocrystals, and recessed truncated-octahedral …

Neural Network Driven By Electrochemical Performance Data For Predicting The Discharge Termination Time Of Seawater Electrolyte-Based Metal-Air Batteries, Peng-Peng Shen, Yi-Chi Pan, Yu-Rong Liu, Lu-Dan Zhang, Ning Niu, Guan-Jun Wang, De-Kun Yang, Xin-Long Tian, Peng Rao

Journal of Electrochemistry

Seawater electrolyte-based metal-air batteries exhibit great promise for marine energy supply systems. However, conventional statistical analysis methods, though applicable to seawater metal-air battery lifetime prediction, have inherent limitations of insufficient prediction accuracy and large error. Herein, a deep time-series regression framework based on InceptionTime and incorporating prior-biased attention pooling is proposed to construct a nonlinear mapping between electrochemical performance sequences and the discharge termination time of catalysts. Specifically, chronoamperometric profiles are employed to extract long-term stability features, while prior knowledge derived from linear sweep voltammetry is introduced to strengthen the attention weighting over critical potential regions. Under a nested leave-one-catalyst-out …

Unveiling Cuo-Doped Mwcnts Incorporated Polycaprolactone As Effective Photocatalytic Nanomembranes For Sequestrating Toxic Dyes From Industrial Wastewater And Antibacterial Applications, Hesham Moustafa, Mohamed Mousa, Mohamed Morsy, Gotdon Price, Mohamed H. Hemida, Samah A. Mohamed, Ahmed Helal

Nanotechnology Research Centre

Organic dyes, such as methylene blue (MB), are widely used in the textile and dyestuff industries, which can be released into the environment as major dye pollutants in wastewater, thereby causing serious environmental hazards. The present research aimed to synthesize effective CuO-doped multi-walled carbon nanotubes (MWCNTs) and incorporated into a renewable polycaprolactone (PCL) polymer at varied dosages (i.e., 3, 7, and 10 wt%) to fabricate photocatalytic nanomembranes for toxic dye sequestration. XRD, SEM and FTIR analysis were employed to characterize the structure, morphology and composition of prepared nanoparticles and PCL nanomembranes. The mechanical properties and antibacterial performance of prepared nanomembranes …

Synthesis, Thermal Stability, And Ionic Conductivity Of Phenyl-Extended Viologen Ditriflate Salts: Tailoring Properties Via Oxyethylene Chain Length, Seonghyeok L. Cox, Emily Moon, Si L. Chen, David King, Haesook Han, Pradip K. Bhowmik, Calvin Ng Yi Bin, Thamil Selvi Velayutham, Alfonso Martinez-Felipe

Chemistry and Biochemistry Faculty Research

Six new phenyl-extended viologen salts with oxyethylene groups paired with triflate anions (OTF) have been synthesized using anionic ring-opening and ring-closing reactions (ANRORC) and metathesis reactions with LiOTf salts. The salts, which contain terminal oxyethylene chains of varying lengths ((CH₂CH₂O)_n, n = 1, 2, 3, 4, 5, and 7), are named PEOn-OTF. These materials exhibit a fluorescence response and possess high thermal stability, with processing windows up to approximately 300 °C, as confirmed by thermogravimetric analysis. While samples with short chain lengths (n = 1, 2, and 3) undergo crystallization observed …

Techno-Economic Analysis Of Implementing Carbon Capture And Storage (Ccs) At The Punagaya 2×100 Mw Coal Power Plant, Ricky Andreas Kristianto Siringoringo, Rahma Muthia, Widodo Wahyu Purwanto

Journal of Materials Exploration and Findings

The increase in greenhouse gases due to the combustion of fossil fuels is one of the major drivers of global warming and consequently drives the development of low-carbon technologies such as Carbon Capture and Storage (CCS). The aim of this study is to evaluate the technical and economical feasibility of the implementation of CCS technology in the Punagaya Subcritical Coal-Fired Power Plant (CFPP) 2×100 MW as a part of the energy transition strategy towards Net Zero Emissions (NZE) 2060. The simulation was carried out using Aspen HYSYS software, including coal combustion, CO₂ capture through MDEA-PZ solvent, dehydration, transportation, and storage …

Exploring Red Palm Oil As A Sustainable Plasticizer For Carbon Black-Filled Ssbr/Br Tire Tread Compounds: A Comparative Evaluation Of Commercial Alternatives, Norma Arisanti Kinasih, Mohamad Irfan Fathurrohman, Santi Puspitasari, Dewi Kusuma Arti, Abdulhakim Masa

Journal of Materials Exploration and Findings

This study investigates the application of red palm oil (RPO) as an alternative vegetable oil resource to substitute petroleum-based plasticizers, which have environmental and health concerns, in carbon black (CB)-filled SSBR/BR tire tread compounds. The plasticizing effects of RPO were thoroughly evaluated by comparing them with a commercial bio-based plasticizer, Epoxidized Soybean Oil (ESBO), and two safer petroleum-based oils, Naphthenic Oil (NYNAS) and Treated Distillate Aromatic Extract (TDAE). The initial investigation shows that fatty acid composition is imposing regarding the plasticizing effect. The higher unsaturated fatty acid content in RPO than in ESBO improved tensile strength and degraded rolling resistance …

Metallurgical Investigation Of A Modified Eye Bolt Failure Caused By Improper Weld Extension, Specification Deviation, And Crevice Corrosion, Dimas Muhammad Fawwaz, Reza Miftahul Ulum, Johny Wahyuadi Soedarsono, Yudha Pratesa

Journal of Materials Exploration and Findings

A modified eye bolt from the David Arm Manhole Storage Tank underwent thorough metallurgical study due to the consequences of the bolt's malfunction during operation. Safety issues arose when the manhole door detached during operation. The mechanical testing and chemical composition analysis of the bolts indicated they were manufactured from an ASTM A193 Grade B7 material used for high-temperature bolting. This material did not conform to the engineering drawing, which mentioned SA 563A, which is about nuts, not bolts. This contradiction clearly shows that the eye bolt which was installed does not conform to the intended design. Welded connections of …

Rejection Of Fe (Iron) And Kmno4 (Organic Substance) Parameters In Peat Water Using Organic Membranes, Muhamad Rafli Sakti Mulia Gonera, Siti Umi Kalsum, Sarah Fiebrina Heraningsih

Journal of Materials Exploration and Findings

Peat water is a surface water source widely used by people in swampy and lowland areas, but it has poor quality characteristics such as high organic matter content, low pH, and dissolved metal levels such as iron that exceed the threshold. These conditions can cause health problems and reduce the quality of clean water so that effective treatment technology is needed. This study aims to analyze the effectiveness of ultrafiltration membranes made from chitosan from shrimp shell waste in rejecting iron (Fe) and organic substances in peat water, and to determine the effect of pressure on separation performance. This study …

Percolation-Induced Thermo-Rheological Transitions In Biobased Graphene Nanoplatelet Nanofluids, Abiodun A. Saka, Tobechukwu K. Abor, Anthony C. Okafor, Monday U. Okoronkwo

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Biobased lubricants with thermally responsive rheology are increasingly needed for high-efficiency mechanical systems. Graphene nanoplatelet (GnP) nanofluids in vegetable oils are promising candidates, yet their percolation-driven thermo-rheological transitions remain insufficiently understood. In particular, the coupled concentration–temperature landscape controlling network-mediated flow transitions has not previously been established. Here, surfactant-free GnP nanofluids were prepared in high-oleic soybean oil (HOSO) at concentrations of 0.025–2.15% v/v (ϕ), and their rheological response was mapped between 25°C and 80 °C under steady-shear and oscillatory conditions. Below the percolation threshold (ɸ ≤ 0.1% v/v), the nanofluids exhibit near-Newtonian behavior, moderate reversible viscosity enhancement, and classical Arrhenius-type temperature …

Synchrotron X-Ray Diffraction Method For Continuous Strain Analysis Across Heterogenous Material Interface Layers, Sierra Damon

Discovery Day - Daytona Beach

Synchrotron X-ray diffraction method for continuous strain analysis across heterogenous material interface layers   The transfer of strain across a material interface is a relevant concept to quantify for numerous aerospace applications that involve coatings applied to substrates of different materials, particularly in the field of high temperature materials. X-ray diffraction (XRD) is a metrology technique capable of resolving strain within an arbitrary material by quantifying the shifts of Bragg peaks with respect to an unstrained sample and has seen increased use due to the capability of XRD to perform in-situ measurements on materials in extreme environments. Since different materials have …

Synthesis And Characterization Of Carbon Quantum Dots And Gold Nanoparticles For Norovirus Biosensing Applications In Water Systems, Breanne Evans

Master's Theses

Rapid, reliable detection of viral pathogens remains a significant challenge across water-treatment and environmental monitoring systems, including drinking-water, wastewater, water reuse, and environmental surveillance applications. Waterborne viral contamination can pose substantial public-health risks, making early detection essential for protecting water quality and responding quickly to treatment failures or contamination events. Direct potable reuse (DPR) is one particularly demanding example because it requires continuous verification of treatment performance and the broader need for rapid virus monitoring extends across many water-treatment and environmental surveillance applications. Norovirus is a priority target because of its widespread occurrence in wastewater, environmental persistence, and exceptionally low …

Exploring The Nature And Role Of Local Cation Ordering In Disordered Rock Salt Cathodes For Li- And Na-Ion Batteries, You Wang

Chemistry and Chemical Biology ETDs

Cation-disordered rock-salt (DRX) cathodes provide a highly tunable platform for next-generation Li- and Na-ion batteries, but their electrochemical behavior is strongly influenced by local structural features hidden in average crystal structures. This dissertation systematically investigates local cation ordering in Li- and Na-based DRX cathodes to understand its effects on Li+/Na+ transport, redox activity, structural evolution, and electrochemical performance. In Li-based systems, Raman spectroscopy and electrochemical analysis reveal that local layered cation ordering in Mn- and Fe-based DRX cathodes is closely correlated with electrochemical behavior. Over-stoichiometric Li-based DRX oxyfluorides further demonstrate that excess Li can regulate local cation ordering, improve Li+ …

Dynamic Reconstruction Engineering Of Anti-Corrosion Ni-Based Anodes For Alkaline Seawater Electrolysis, Yi-Gang Zhang, Wen-Wen Xu, Tian-Yu Zhang, Zhi-Yi Lu

Journal of Electrochemistry

Green hydrogen production via alkaline seawater electrolysis offers an environmentally sustainable and potentially cost-effective route to address both energy and climate challenges. Achieving long-term anode stability under complex ionic environments and industrial current densities remains a central bottleneck. Specifically, Ni-based anodes exhibit intense surface reconstruction during the oxygen evolution reaction, necessitating dynamic anti-corrosion strategies. This mini review systematically summarizes reconstruction engineering approaches to develop anti-corrosion Ni-based anodes of alkaline seawater electrolysis across increasingly complex ionic environments from simulated seawater to real seawater: (i) Cl^– dominated; (ii) Cl^– with co-existing oxyanions, and (iii) Cl^–  with co-existing Br^{– …}

Preparation And Performance Study Of In-Situ Self-Assembled Biphasic Smmn2O5-Nimn2O4 Composite Cathode, Neng-Chu Xia, Yu Zhou, Qin Wang, Jia-You Zhang, Chun Yu, Yang Zhang, Wan-Bing Guan, Jian-Xin Wang

Journal of Electrochemistry

Mullite-structured oxides exhibit excellent oxygen reduction reaction activity, possess a low thermal expansion coefficient due to their unique crystal structure, and can eliminate the need for a barrier layer and simplify the preparation process as they contain no alkaline earth elements. Thus, they hold great promise as novel cathode materials for solid oxide fuel cells. In this work, a mullite-spinel-structured SmMn₂O₅-NiMn₂O₄ (SMO-NMO) composite cathode was one-step synthesized via a solid-liquid composite route, and its in-situ self-assembly enabled good compatibility with the electrolyte without any barrier layer. Characterization results showed that the SMO:NMO = …

In-Situ Stm Visualization Of Molecular Structural Evolution During Electrochemical Oxidation Coupling Of Para-Aminothiophenol On Au(111), Zi-Wei Ma, Tai-Rui Wu, An-Ni Zheng, Lai-Ke Chen, Yuan-Hui Xiao, Zhao-Bin Chen, Qing-Na Zheng, Jian-Zhang Zhou, Jia-Wei Yan, De-Yin Wu

Journal of Electrochemistry

Para-aminothiophenol (PATP) is not only a widely-used probe molecule in the field of surface-enhanced Raman spectroscopy (SERS), but also an important model molecule for interfacial reactions, exhibiting distinct photo- and electro-oxidation pathways, so that PATP is selectively activated under different external fields. The evolution of products and intermediates during electrochemical oxidative coupling remains unknown. In this study, we have investigated the dynamic electrochemical oxidation process of PATP on the Au(111) surface using cyclic voltammetry, electrochemical (EC)-SERS, and in situ electrochemical scanning tunneling microscopy (EC-STM). The results showed that PATP forms an unsaturated adsorption coverage on Au(111) in an acidic solution. …

Li+/Na+ Hybrid Ion Conduction Mechanism In The Superionic Conductor Li3–XNaXZr2Si2Po12, Yi-Hong Wu, Xia Xie, Lei Zhu, Mu-Ran Yu, Guo-Tai Zhang, Jun-Chao Chen, Shu-Ying Sun, You-Wei Wang, Wei-Ping Tang

Journal of Electrochemistry

Hybrid ion conductors that transport multiple ionic conductive species provide a useful platform for understanding how mixed-ion transport governs ionic conductivity within a single phase. However, the controlled introduction of multiple mobile ions into solid-state electrolytes and a mechanistic understanding of their migration within the framework remain challenging. Herein, a skeleton-retained Li⁺↔Na⁺ cationic exchange was used to simultaneously induce Li⁺ and Na⁺ cations into the NASICON-type framework of Li_3–xNa_xZr₂Si₂PO₁₂ (0 < x < 3). We show that the interpenetration of NaO₆ and NaO₈ coordination polyhedra significantly influences the ionic conductivity of hybrid ion conductors. Computational …

Distinct Co2 Electroreduction Behaviors Over Planar And Non-Planar Cobalt Molecular Catalysts, Ru Jia, Cheng-Biao Zhu, Zi-Mo Zhang, Tuo Wang, Kai-Cong Yang, Guang-Zhe Wang, Yang Hu, Ting-Ting Zhang, Zhen-Wei Wei, Li Xiao, Gong-Wei Wang, Lin Zhuang

Journal of Electrochemistry

Molecular catalysts serve as ideal platforms for studying electrocatalytic reaction mechanisms. While current research mainly focuses on modulating central metals or surrounding ligands, the influence of molecular spatial configuration remains largely unexplored. Herein, we synthesized two cobalt complexes with similar ligand environments but distinct spatial geometries, a planar cobalt hexaazamacrocyclic complex (CoHAM) and a non-planar acyclic Co(phen)₂Cl₂, and evaluated their performance in CO₂ reduction reaction (CO₂RR). The planar CoHAM exhibited dramatically superior CO₂RR performance compared to the non-planar Co(phen)₂Cl₂. Through a series of combined analyses using in-situ …

Distribution And Transport Of Lithium Ions At Interfaces Between Graphite And Carboxymethyl Celluloses, Zi-Jun Huang, Zhen-Ying Zheng, Hua-Wei Cao, Jian Wang, Qing-Feng Zhang, Sheng-Li Chen

Journal of Electrochemistry

Carboxymethyl cellulose (CMC) is a water-processable binder widely used for graphite anodes. However, a microscopic understanding of why the identity of CMC counterions (Li⁺/Na⁺/K⁺) strongly affects electrode performance remains limited. Here, molecular dynamics (MD) simulations are used to track Li⁺ transport accessibility across electrolyte/CMC/graphite three-phase interfaces, comparing pure CMC-Li, CMC-Na, CMC-K, and mixed-counterion CMC binders. We find that CMC-Li sustains a continuous Li⁺ transport pathway from the electrolyte through the binder phase toward graphite. In contrast, in CMC-Na and CMC-K, Na⁺/K⁺ ions preferentially enrich at the graphite/binder interface, forming …

Lafe0.925ti0.075o3 Perovskite Coated With Ethyl Cellulose: A High-Stability, Low-Hysteresis Platform For Advanced Humidity Sensing, Akhmad Futukhillah Fataba Alaih, Djoko Triyono, Rifqi Almusawi Rafsanjani

Makara Journal of Science

Humidity sensors are pivotal in numerous sectors, such as environmental monitoring, industrial automation, and health-care. This study presents the fabrication and detailed evaluation of an advanced humidity sensor using ethyl cellulose (EC)-coated LaFe_0.925Ti_0.075O₃ (LFTO) perovskite nanoparticles synthesized via the sol-gel method. The LFTO nanopar-ticles exhibited a mesoporous structure with an enhanced surface area, which significantly improved their moisture adsorption capabilities. The innovative application of EC coating addresses critical substrate adhesion issues, enhancing mechanical stability without compromising sensor sensitivity. Comprehensive performance evaluations revealed minimal hysteresis (

Rheological Protocol To Assess And Optimize Latex Coagulation Dynamics For The Thin Glove Coagulant Dipping Process, Monday U. Okoronkwo, Kok Kong Ng, Wolfram Franke, Gaurav Sant

Chemical and Biochemical Engineering Faculty Research & Creative Works

Many products that directly impact the quality of human life today — gloves, catheters, condoms, and baby bottle teats — are made through the latex-dipping technology. While a variety of methods have been developed – e.g., particle counting, turbidimetry, microscopy, and light scattering – which are suitable for studying the coagulation of latex at very low concentrations, much less work has focused on methods suitable for in-situ characterization of latex coagulation in concentrated solutions (e.g., as relevant to the dipping process). This paper presents a process-relevant rheological protocol for assessing and optimizing latex coagulation dynamics for the thin glove coagulant …

Tuning Ion Mobility And Molecular Confinement In High-Performance Polymer Electrolytes For Energy Storage, Ezzeldien Yousef Muhammed Yousef

Theses and Dissertations

This research addresses the critical energy density limitations of aqueous supercapacitors, which are traditionally constrained by the narrow electrochemical stability window (ESW) of water 1.23 V. By employing two distinct molecular engineering strategies, this study developed high-performance electrolyte systems that significantly extend voltage stability and thermal resilience.

The first system, CsBr@PAM/HA, utilizes a polyacrylamide and hyaluronic acid hydrogel matrix. This system exploits the chaotropic nature of Cs⁺ ions to disrupt the aqueous hydrogen-bonding network, enhancing ionic conductivity to 104 mS cm^-1. Through systematic salt screening, CsBr was identified as the optimal electrolyte, enabling a stable 2.0 V …

Investigation Of Portland Limestone Cement Blended With Biochar From Downdraft Gasification: Hydration Kinetics, Microstructure, Rheology, And Performance Mechanisms, Ugochukwu Ewuzie, Paul C. Ani, Abdulkareem O. Yusuf, Joseph D. Smith, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

The widespread adoption of Portland Limestone Cement (PLC) in U.S. concrete production has necessitated research into commercially available supplementary cementitious materials (SCMs) for formulating high-performance, low-carbon blended binders with PLC. This study investigated the influence of biochar (BC) in biochar-PLC composites (CBCs), focusing on hydration kinetics, microstructure, rheology, pore-solution chemistry, compressive strength, and the underlying mechanisms. Biochar was produced via downdraft gasification at 850 °C and incorporated into PLC at 5, 7, and 10% substitution by mass. Isothermal calorimetry and hydration data modeled using the Knudsen equation revealed that BC retarded early hydration but improved hydration degree and later-age heat …

Characterization Of The Thermally Driven Red Hue Effect In Coated And Uncoated Concrete Systems: Implications For Post-Fire Assessment In Wildland Urban Interface Communities, Juan C. Palominos Jr

Master's Theses

The increasing frequency and intensity of Wildland-Urban Interface (WUI) wildfires, such as the destructive 2025 Pacific Palisades Fire that destroyed over 6,000 structures, have underscored the urgent need for rapid post-fire safety assessment methodologies. This study sought to quantitatively characterize the Thermally Driven Red Hue Effect (TRHE), a unique, irreversible color shift observed in architectural coatings and concrete substrates, to determine its reliability as a permanent visual record of thermal exposure. Concrete substrates were formulated with three distinct coarse aggregates: gold granite (14.7% Fe), red cinder (22.4% Fe), and green rock (33.6% Fe) and coated with a 20 PVC waterborne …

Thermally Induced Color Changes In Iron Oxide Containing Coatings, Tabatha Whitfield

Master's Theses

Wildland-urban interface (WUI) fires and residential conflagrations present significant challenges for post-fire damage and fire propagation analysis. CAL FIRE observed reddening in architectural coatings during the 2025 Pacific Palisades fire with no determination of the cause. While heat-induced color change of infrastructure coatings has been studied, its potential use as a thermal exposure indicator in residential fire events remains largely unexplored. The objective of this study was to characterize the heat-induced color change of yellow iron oxide containing coatings subjected to thermal exposures, replicating residential fire conditions. The coatings were applied to commonly used building materials and exposed to direct …

Thermally Induced Color Changes In Iron Oxide Pigments Used In Architectural Coatings, Han Diep

Master's Theses

The 2025 Palisades Fire was one of the most destructive wildfires in the history of Los Angeles, destroying thousands of structures and severely impacting the communities after. This widespread destruction demonstrated an urgent need for more effective wildfire prevention strategies. Architectural coatings do not only provide aesthetics and protection against environmental conditions but can also function as a thermal indicator when a fire breaks out. This study examines the thermally induced color transformation of iron oxide pigments, commonly used in earthtone paint, to provide information relevant to CAL FIRE for improved analysis of wildland-urban interface (WUI) fire behavior and mitigation …

Mediating Energy And Charge Transfer Dynamics Of Lead Halide Perovskite Nanocrystals Via Surface Chemical Approaches, Aaron S. Malinoski

Dissertations, Theses, and Capstone Projects

Energy and charge transfer are the fundamental mechanisms by which semiconductor nanocrystals interact with their external environment and underpin all light-conversion related applications. Lead halide perovskite nanocrystals (PNCs) are a relatively new class of semiconductor nanocrystals that possess a unique and dynamic surface chemical environment. Investigations into the influence of these surface chemical conditions on the electronic coupling between surface-bound molecular acceptors and the perovskite nanocrystals, and how the surface chemistry can be manipulated, in turn controlling the charge and energy transfer mechanisms, is the focus of this dissertation. Through ligand-shell engineering using commercially available, inexpensive small molecules, the surface …

Modulating Electronic Structure With Linearly Fused Pyrazine Units For High-Voltage And Stable Zinc-Organic Batteries Cathode, Min-Jian Zhao, Li-Bin Zhang, Jin-Tao Wang, Kun Ding, Hai-Mei Liu, Yong-Gang Wang

Journal of Electrochemistry

High-voltage n-type organic cathode materials are critical for constructing zinc-organic batteries (ZOBs) with high energy density and long cycle life. However, the intrinsically unfavorable electronic structures and relatively high LUMO energy levels of most n-type materials often lead to sluggish kinetics, high solubility, and suboptimal discharge voltages (< 0.8 V). Here, we design a small molecule, quinoxalino[2’,3’:5,6]pyrazino[2,3-f][1,10]phenanthroline (DPQP), as a ZOB cathode by introducing locally electron-deficient motifs into the conjugated backbone of aromatic compounds. The linearly fused pyrazine units extending the pyrazine–benzene framework effectively optimize the electronic structure, thereby significantly enhancing the discharge voltage. Meanwhile, the expanded π-conjugated plane suppresses dissolution and accelerates charge-transfer kinetics. Benefiting from these features, the DPQP electrode exhibits an exceptional increase in average operating voltage from 0.61 V to 1.07 V (vs. Zn²⁺/Zn) at 0.1 A·g^–1, with an overpotential of only 140 mV. Notably, no discernible voltage decay occurs as the current density increases, indicating rapid and highly reversible redox kinetics. Furthermore, the DPQP cathode delivers outstanding cycling stability, maintaining over 2000 h of continuous operation at 0.1 A·g^{–1 …}