Single-step Heat Research Articles

Curdlan/sodium carboxymethylcellulose composite adsorbents: A biodegradable solution for organic dye removal from water

Composite adsorbent comprised of curdlan (CURD) and sodium carboxymethylcellulose (CMC) were fabricated through a single-step heating process, targeting the removal of methylene blue (MB) from wastewater. The CURD/CMC composite adsorbents had a honeycomb porous structure. The integration of CMC not only increased the storage modulus of the CURD/CMC composite hydrogels but also affected the thermal stability and swelling behavior of the composite adsorbents in different pH solutions. Specifically, the addition of 1.2 % CMC increased the peak temperature (184.73 °C) of CURD/CMC composite adsorbent melting by 5.99 °C compared to CURD adsorbent. The addition of CMC improved the swelling ratio of the composite adsorbent at pH 3,7, and 12 with swelling ratio up to 918.07 %. The synergistic interaction between CURD and CMC led to an enhanced adsorption capacity of the aerogel for MB, achieving a maximum adsorption capability of 385.85 mg/g. Adsorption isotherm assessments further demonstrated that the Langmuir isotherm model well fitted the adsorption data of the composite adsorbent on MB. Collectively, these findings underscore the potential of the developed biodegradable adsorbents as promising adsorbents for efficiently eliminating organic dyes from water.

Hexavalent chromium removal using reduced graphene oxide-zinc oxide composite fabricated via simple pyrolysis method

The contamination of water by heavy metals from various industrial effluents is a significant factor contributing to the scarcity of clean water worldwide. To address this issue, there is a need to develop low-cost adsorbents to remove heavy metals from contaminated water reduced graphene oxide (rGO) based composites are efficient adsorbers of heavy metals. In this study, a green and rapid single-step heating process was utilized to prepare both rGO and rGO/ZnO composite materials, avoiding the use of any toxic reagents. The rGO/ZnO composite synthesized from sucrose and zinc acetate demonstrates a remarkable ability to adsorb hexavalent chromium (Cr(VI)). The Cr adsorption studies were carried out by varying adsorbent, contact time, initial pH, and concentration. The adsorption efficiency of the composite is five times higher than that of pure rGO. The adsorption mechanism of Cr(VI) onto the adsorbent is electrostatic interaction, complexation, pore filling, and reduction, identified through Zeta potential measurement, BET, EDX, and XPS analysis. These studies suggest that rGO/ZnO composite has great potency as a cost-effective and efficient adsorbent for removing Cr(VI) contaminants from industrial effluents.

Effect of wire-arc directed energy deposition on the microstructural formation and age-hardening response of the Mg-9Al-1Zn (AZ91) alloy

In recent years, wire-arc directed energy deposition (waDED), which is also commonly known as wire-arc additive manufacturing (WAAM), has emerged as a promising new fabrication technique for magnesium alloys. The major reason for this is the possibility of producing parts with a complex geometry as well as a fine-grained microstructure. While the process has been shown to be applicable for Mg-Al-Zn alloys, there is still a lack of knowledge in terms of the influence of the WAAM process on the age-hardening response. Consequently, this study deals with the aging response of a WAAM AZ91 alloy. In order to fully understand the mechanisms during aging, first, the as-built condition was analyzed by means of high-energy X-ray diffraction (HEXRD) and scanning electron microscopy. These investigations revealed a fine-grained, equiaxed microstructure with adjacent areas of alternating Al content. Subsequently, the difference between single- and double-step aging as well as conventional and direct aging was studied on the as-built WAAM AZ91 alloy for the first time. The aging response during the various heat treatments was monitored via in situ HEXRD experiments. Corroborating electron microscopy and hardness studies were conducted. The results showed that the application of a double-step aging heat treatment at 325 °C with pre-aging at 250 °C slightly improves the mechanical properties when compared to the single-step heat treatment at 325 °C. However, the hardness decreases considerably after the pre-aging step. Thus, aging at lower temperatures is preferable within the investigated temperature range of 250-325 °C. Moreover, no significant difference between the conventionally aged and directly aged samples was found. Lastly, the specimens showed enhanced precipitation kinetics during aging as compared to cast samples. This could be attributed to a higher amount of nucleation sites and the particular temperature profile of the solution heat treatment.

Enhancing high-temperature strength and ductility in laser powder bed fusion Ti–6.5Al–2Zr–1Mo–1V alloy via heat treatment optimization

Heat treatment (HT) is an effective way to attain the desired microstructure and mechanical properties in laser powder bed fusion (LPBF) Ti–6.5Al–2Zr–1Mo–1V (TA15). However, previous studies only obtained the high tensile ductility of LPBF TA15 but were accompanied by a large loss of strength, which was unable to achieve balanced mechanical properties. Here, we evaluated the tensile properties of LPBF TA15 at their usage temperatures (500 °C), and a superior combination of high-temperature strength and ductility in LPBF TA15 was successfully achieved via a single-step heat treatment. After the heat treatment close to the β transus temperature (950 °C as used in this study), the tensile strength of the sample was ∼30% higher than that of as-cast TA15, accompanied by the obvious enhancement of ∼67% in elongation. The high strength originated mainly from the secondary α-phase and discontinuous grain boundary α-phase (GB-α), whereas the large ductility correlates to the complete decomposition of brittle α’ martensite. Discontinuous GB-α could inhibit crack initiation at the grain boundary and the fine secondary α-phase impeded the dislocation motion, which could enhance the tensile strength. Meanwhile, the α lath directions after heat treatments were far away from the 45° of the load direction, which also avoided the localized deformation within α laths and thus improved the fracture resistance of LPBF TA15.

Single-step insertion of M-Nx moieties in commercial carbon for sustainable bifunctional electrocatalysis: Mapping insertion capacity, mass loss, and carbon reconstruction

Atomically dispersed earth-abundant metals in N-doped carbon (M-N-Cs) have emerged as a new class of electroactive materials that can match not only the performance of the precious metals but can catalyze both the cathodic and the anodic reactions due to their bifunctional behaviour. This inspires the development of simpler strategies for scale-up production since the existing ones rely on precursors whose commercial viability is not yet ascertained. Herein, we demonstrate the insertion prospects of M-Nx (M = Fe, Co, Ni) moieties, the electrocatalytic centers in the M-N-Cs, into commercial carbon to establish that a single-step heating of the inexpensive precursors is sufficient to generate bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with efficiencies that bypass the majority of the known catalysts. Further importantly, we quantify both the ORR and OER trends and the metal insertion limits for each metal while maintaining an atomic dispersion, without the formation of surface migration-induced clustering, because such clustering is inevitable in the existing processes to necessitate an extra acid-leaching step to remove them. We further quantify and explain for each metal a negative mass balance originating from anomalous mass loss of both metal and carbon content, and a massive reconstruction of the carbon backbone catalyzed by the very metal, an event documented for the first time though it ought to be associated with other M-N-C syntheses too. The study establishes an incredibly simple and inexpensive strategy for the realization of M-N-Cs and outlines the parameters to be considered during mass-production.

Facile and Scalable Fabrication of Conductive Ceramic Composite for Energy Conversion and Electromagnetic Interference Shielding

A conductive ceramic composite (CCC) based on carbonized phenolic resin is fabricated via a facile and scalable dry-pressing method. A conductive carbonaceous precursor solution is homogeneously mixed with a ceramic precursor. Subsequently, carbonization and ceramicization are achieved simultaneously in a single heating process. The carbonized materials endow the composites with excellent electrical conductivity and reliable cyclic heating properties. The temperature of the obtained composites is approximately 386 °C at 12 V after 10 min and 400 °C at 20 V after 48 s, and their energy consumption is low. Thermal images show that an even heat distribution is achieved on the composite surface, and that the electro-thermal performance can be adjusted by changing the electrical circuit arrangement (series or parallel circuits). In addition, the ceramic composites exhibit favorable electromagnetic interference (EMI) shielding performance of 26.2 dB at 8.2 GHz and improved photothermal conversion effect compared with the pristine ceramic. More importantly, this single-step heating provides a convenient and cost-effective approach for producing CCCs, thereby enabling the scalable production of conductive ceramics for electro-thermal applications. The excellent electrical performance facilitates the application of ceramic composites in Joule heating (e.g., deicing, boiling water, and cooking) and EMI shielding.

Heterogeneous lamella design to tune the mechanical behaviour of a new cost-effective compositionally complicated alloy

A heterogeneous lamella (HL) design strategy was applied to manipulate mechanical properties of a new cost-effective Fe35Ni35Cr25Mo5 compositionally complicated alloy (CCA). The HL structure was produced by single-step heat treatment (800 °C for 1 h) after cold rolling. This HL structure consists of alternative lamellae regions of coarse-grained FCC matrix (5‒20 μm), and regions containing ultra-fine grains or subgrains (200‒500 nm) together with nanoprecipitates (20‒500 nm) and annealing twins. As compared with other cost-effective CCAs, the 800 °C annealed sample with HL structure demonstrated a comparable tensile property, with yield strength over 1.0 GPa and total elongation of ~13%. Formation of the annealing twins and nanoprecipitates decorated HL structure was a result of the concurrent partial recrystallization and precipitation of σ phase at the shear bands with a high density of lattice defects (e.g. high-density dislocation walls and deformation twins). The latter restricted the growth of recrystallized grains, leading to the formation of ultrafine subgrains within the HL structure. The high yield strength resulted from the multistage hetero-deformation induced (HDI) strengthening and precipitation strengthening associated with heterogeneous lamella structures containing nanoprecipitates. The ductility was originated from the coexistence of multiple deformation mechanisms, which started with dislocation slip and formation of stacking faults at the initial stage, followed by nano-twinning at the higher strain level. This HL design strategy, comprising composition and thermomechanical process designs, and the resultant microstructure tuning, open a broader window for the development of cost-effective CCAs with enhanced performance.

Interfacial interaction of graphitic carbon nitride/nanodiamond nanocomposites toward synergistic enhancement of photocatalytic degradation of organic contaminants

Graphitic carbon nitride (g-C3N4) has been widely used in various photocatalyst applications. However, compared with conventional metal-based photocatalysts, it exhibits low photocatalytic activity because of the low mobility of its charge carriers. In this study, g-C3N4/nanodiamond (ND) nanocomposites were fabricated via a facile single-step heating strategy. Under visible-light irradiation, the optimal g-C3N4/ND nanocomposites with 1.0 wt% ND content exhibited an RhB degradation rate more than two times greater than that of the g-C3N4. In addition, reutilization experiments showed that the g-C3N4/ND nanocomposites exhibit good stability and reusability. This remarkable enhancement of the photocatalytic activity was attributed to the interfacial effect between g-C3N4 and ND, which reduces energy-wasteful electron–hole recombination and promotes charge-separation efficiency. Such an approach could accelerate the development of composites for photocatalyst applications and provide more rational guidance and fundamental understanding toward realizing the theoretical limits of interfaces.

Strain partitioning enables excellent tensile ductility in precipitated heterogeneous high-entropy alloys with gigapascal yield strength

High entropy alloys (HEAs) with grain-scale heterogeneous structure and coherent precipitates have shown gigapascal strength and considerable ductility. However, the origins of the excellent ductility of the HEAs with both precipitates and grain-scale heterogeneous structures are relatively less explored and not well understood. It is also still challenging to obtain such precipitated heterogeneous HEAs through efficient and economical thermomechanical processing procedures. Here, through single-step heat treatment, we developed a Ni2CoCrFeTi0.24Al0.2 HEA with an excellent yield strength of ~1.3 GPa and tensile elongation of ~20%. Using multiple length-scale microstructure characterizations and micro-digital image correlation analysis, we revealed the strengthening and toughening mechanisms of the novel HEA. Our results showed that the grain-scale heterogeneous structure with L12 precipitates ranging from ~10 to 100 nm is responsible for the excellent strength-ductility combination. The good ductility is attributed to the strain-partitioning-induced additional deformation modes, i.e., deformation twinning and microbands, as well as the efficient hetero-deformation induced strain hardening effect. The superior yield strength is mainly due to the effective combination of precipitation hardening and dislocation strengthening. These findings not only provide a facile route to develop strong and ductile alloys but also deepen the understanding of the deformation mechanism of hetero-structured materials.

Characterization of Waste-Integrated Multi-hybrid Structure for Enhancing Corrosion Resistance of High-Carbon Steel

Due to their exceptional properties, low-cost high-carbon steels have long been extensively utilized in many industrial applications. However, their corrosion resistance is poor for many applications and requires further enhancement. Various methods have been developed to achieve this, but they suffer from some limitations. In the work presented herein, a single-stage heat treatment process was applied at low temperature and utilizing waste materials for comparison as new resources, being shown to be a cost-effective approach. In the framework of this study, a multi-hybrid coating structure was developed on the surface of high-carbon steel by applying a single-step heat treatment process and utilizing various waste materials, namely metallurgical slag, glass, and automotive shredder residue (ASR). The results reveal that not only was the process completed in a short time but significant enhancements in the corrosion resistance and hardness performance were achieved. Analyses were performed by high-resolution laser scanning confocal microscopy, electron probe microanalysis (EPMA), focused ion beam-scanning electron microscopy (FIB-SEM), and atomic force microscopy (AFM) in peak force quantitative nanomechanical (PF-QNM) mode. The electrochemical corrosion performance was tested using Tafel method. Both the Young’s modulus and corrosion resistance of the steels treated using the waste materials were improved compared with the base material. This approach opens a new perspective for utilizing waste materials to obtain environmentally sustainable products in a cost-effective fashion, thereby reducing reliance on new resources as well as disposal of waste materials in landfill.

Single-Step Heat Treatment for the Restoration of Mechanical Properties of Cold-Strained Mining Support Steel 31Mn4

The steel 31Mn4+QT630 is used frequently for mining support arches. The supports are cold strained, first during service, and again by re-rolling prior to reinstallation, which results in strain hardening and a loss of ductility. Consequently, many of the rerolled arch-segments are not suitable for reinstallation because their mechanical properties are inadequate. The objective of this work was to assess the feasibility of restoration of the required mechanical properties by means of a cost-efficient single step heat treatment. Specimens were cold deformed to different degrees in the range 0 % to 45 % to establish the relation between the degree of cold deformation and the hardness. Differently strain hardened specimens were subjected to subcritical annealing at temperatures 450 °C to 700 °C in the duration 0.5 h to 8 h to determine a suitable time-temperature combinations. Microstructures and mechanical properties were investigated of as-received, cold strained and recrystallized specimens. Tests performed were optical microscopy, scanning electron microscopy, tensile tests, hardness measurements and Charpy impact tests. Elongation at break of the as-received material was below the requirements of the applicable standard, and its microstructure contained significant fractions of pre-eutectoid ferrite and pearlite. Upon cold straining, hardness increased by approximately 2 HV per 1 % of strain. After one-hour recrystallization at 600 °C to 620 °C, the microstructure consisted of a ferritic matrix containing evenly dispersed globular carbide particles. The original ductility was restored, while the elongation, yield strength, and hardness were higher than in the as-received condition. These results confirmed that it is feasible to restore the original mechanical properties of heavily strained profiles with an adequate single-step heat treatment. Furthermore, they indicated that it should be possible to recover the required properties of inhomogeneously strained material with the same set of well optimized heat treatment parameters. Consequently, it should be possible to increase the reuse rate and to decrease the costs for new support arches significantly.

Enhanced cryogenic tensile properties with multi-stage strain hardening through partial recrystallization in a ferrous medium-entropy alloy

We demonstrate the formation of partially recrystallized bimodal microstructures through single-step heat treatment after cold-rolling in Fe60Co15Ni15Cr10 (at%) ferrous medium-entropy alloy that leads to the enhanced yield-strength of ~1.1 GPa and ultimate-tensile-strength of 1.7 GPa at persistent ductility of 61%, evading strength-ductility trade-off. The retention of deformation substructures allows a yield-strength increase by ~79% compared to that in a fully-recrystallized state, together with the modification of mechanical stability without compositional variation, resulting in multi-stage strain hardening capability during tensile deformation at 77 K.

Heterogeneous Lamella Design to Tune the Mechanical Behaviour of a New Cost-Effective Compositionally Complicated Alloy

A novel heterogeneous lamella (HL) design strategy was proposed to improve mechanical properties of a new cost-effective Fe 35 Ni 35 Cr 25 Mo 5 compositionally complicated alloy (CCA). A HL structure was produced by single-step heat treatment (800 °C for 1h) after cold rolling. This HL structure consists of alternative lamellae regions of coarse-grained FCC matrix (5∼20 μm), and regions containing ultra-fine grains or subgrains (200∼500 nm) together with nanoprecipitates (20-500 nm) and annealing twins. The 800 °C annealed sample with HL structure demonstrated a superior tensile property, with yield strength over 1.0 GPa and ductility of ~13%. Formation of the annealing twins and nanoprecipitates decorated HL structure was a result of the concurrent partial recrystallization and precipitation of σ phase at the shear bands with a high density of lattice defects (e.g. high-density dislocation walls and deformation twins). The latter restricted the growth of recrystallized grains, leading to the formation of ultrafine subgrains within the HL structure. The high yield strength resulted from the multistage hetero-deformation induced (HDI) strengthening and precipitation strengthening associated with heterogeneous lamella structures containing nanoprecipitates. The ductility was originated from the coexistence of multiple deformation mechanisms, which started with dislocation slip and formation of stacking faults at the initial stage, followed by nano-twinning at the higher strain level. This HL design strategy, comprising of composition and thermomechanical process designs, and the resultant microstructure tuning, open a broader window for development of cost-effective CCAs with enhanced performance.

Leveraging Solute Segregation in Laser Powder Bed Fusion to Achieve Superior Strength and Ductility Via Single-Step Heat Treatment in Ti-Free Grade 300 Maraging Steel

Maraging steels are Fe-Ni precipitation-strengthened steels that can be heat treated for achieving high strength with an accompanying loss in ductility, a trend common to most metals. We show that the segregation of Ni during laser powder bed fusion, commonly considered a nuisance that is dealt with via solutionizing heat treatments, can be leveraged via direct aging to achieve higher strength and ductility simultaneously, compared to a solutionized and aged condition. The high dislocation density in combination with solute segregation in the as-fabricated material promotes the precipitation of Mo-rich intermetallic phases that are responsible for the high strength, and the Ni segregated regions facilitate austenite reversion during direct aging. The reverted austenite enhances the elongation via transformation-induced plasticity. While overcoming the strength–ductility conundrum, direct aging can significantly reduce the energy and emissions associated with multistep heat treatments, especially in the global tool and die industry, while laser powder bed fusion (LPBF) can enable tools with integrated cooling channels for increased downstream production efficiency.

Site-substitution effect on skyrmion phases of Cd2+-Cu2OSeO3 nanocrystallites

The past decade has seen a significant uptick in research interest to study the materials that can host magnetic skyrmion lattices. The curiosity of such materials is mainly driven by the technological applications of emergent skyrmion lattices that manifest a whirlpool-like spins arrangement. Insulating Cu2OSeO3 reported to host magnetic skyrmion lattices below 60 K and considered as a potential candidate for exploring this new phase of materials. Here in this article, we propose a new synthesis process to grow the Cd2+-substituted Cu2OSeO3 nanocrystallites with variable sizes ranging over 50–200 nm. The proposed method consists of only a single-step heat treatment of 12 h, which is cost-effectivethan the routine solid-state process that requires a rigorous 15–20 days of heat treatment. By employing X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and isothermal magnetization (M-T) measurements, we present a comparative investigation of the structural, electronic and magnetic properties of pristine and Cd2+-substituted Cu2OSeO3 nanocrystallites. As non-magnetic substitution can alter the fundamental magnetic interactions, therefore, Cd2+-Cu2OSeO3 nanocrystallites offer a new methodology to control the magnetic skyrmion phases and its stability.

Improvement of fracture toughness of Nb-Si alloy by two-step heat treatment

In this study, two-step heat treatment is conducted to adjust the microstructure and mechanical properties of Nb-Si alloy with addition of Y. The time and temperature of second-step heat treatment are studied to optimize the process. According to the microstructural observation and the tests of mechanical properties, it is confirmed that the two-step heat treatment can significantly improve the fracture toughness (about 30.3%) of Nb-Si alloy without sacrifice of tensile strength which also increases slightly. The improvement can be attribute to the adjustment of microstructures by the two-step heat treatment: Compared to the silicide after single-step heat treatment, the volume of silicide after two-step heat treatment reduces by 40.6%; The silicides with sharp corners tend to be spheroidized by the two-step heat treatment. The proper micro-cracks introduced by the two-step heat treatment are also the reason for improvement of fracture toughness which can promote the crack deflection and crack bridge to toughen the Nb-Si alloy. The optimal fracture toughness about 32.6 MPa·m1/2 can be obtained after the first-step heat treatment at 1450 °C for 12 h and the second-step heat treatment at 1100 °C for 10 h.

Production of carbon coated Al-foams and evaluation of their mechanical response

The feasibility of a cost-efficient method to produce carbon coated Al-foams in a single-step heating process is investigated. In this context, a dissolution-sintering process for manufacturing metal foams is developed using raw cane sugar as both the space holder material and the carbon generating medium. The structural characteristics of the produced carbon coated Al-foams were evaluated by XRD, Raman and SEM analyses. Static compression tests were conducted to determine the mechanical response of the produced carbon coated Al-foams. The produced carbon coated Al-foams were fully covered with an external carbon layer having a relatively uniform thickness, despite the inherent complex 3D surface of the foam. The carbon deposition process led to a significant increase of the compression strength of the Al-foam. A strain softening behavior was observed for the carbon coated Al-foams attributed to micro-cracking of aluminum carbides. The produced carbon coated Al-foams can potentially be used as a catalyst support structure.

Evolution of lamellar microstructures in a cast TNM alloy modified with boron through single-step heat treatments

The processing route of the current TNM alloy (Ti-43.4Al–4Nb–1Mo-0.5B [in at %]) involves casting/HIP'ing plus forging and multiple heat treatments to achieve the required properties. This study seeks to design a modified TNM alloy with superior properties by utilising a simpler processing route, namely casting/HIP'ing plus a single-step heat treatment. The modified alloy composition was melted, cast, treated with HIP and given various heat treatments at selected temperatures near TG (gamma solvus). Images of the samples' microstructures were produced with a scanning electron microscope (SEM) and were evaluated with quantitative image analysis. Phase transformations as a function of temperature were determined using differential scanning calorimetry (DSC). These experimental results were assessed and integrated to identify a single-step heat treatment (1260 °C/1 h/30 K/min) that generates a two-phase (γ + α2) nearly fully lamellar (NFL) microstructure in the cast/HIP-treated material. The resulting FL microstructure was characterized by refined colonies consisting of irregularly arranged laths with apparently low anisotropy, which may potentially yield higher temperature mechanical properties in comparison with TNM-NL.

Effect of Soaking Temperature on Carbide Precipitation, Hardness, and Wear Resistance of High-Chromium Cast Iron

Different variants of high-chromium cast iron are commonly used for wear-resistant applications in mining and steel industries. These alloys are often used in the as-cast condition that limits the optimization of wear properties through microstructural engineering. This paper aims at improving the wear resistance of 20Cr–2C cast iron through an inexpensive single-step heat treatment. In the present study, samples were soaked at temperatures between 700 and 1200 °C at an interval of 100 °C and were air-cooled for destabilization of primary carbide networks. Detailed microstructural analysis was carried out using a scanning electron microscope coupled with electron probe micro-analysis. Image analysis technique was used to determine the effect of soaking temperature on fraction of primary and secondary carbides. Hardness and dry sliding wear tests were conducted to determine the effect of microstructure on mechanical and wear properties. It was observed that the network of primary carbide began to break only at soaking temperature of 1000 °C and above. Up to 800 °C, there was coarsening of primary carbides that led to lowering of hardness and deterioration of wear resistance. At 900 and 1000 °C, precipitation of secondary carbides was observed. At 1100 °C, maximum hardness and wear resistance were achieved. This was attributed to disintegration of primary carbides and the highest fraction of finely dispersed secondary carbides. At 1200 °C, most of the secondary carbides dissolved in the matrix which resulted in sharp fall in hardness and wear resistance. Micro-mechanism of wear was studied using an optical laser scanning microscope. Post-wear hardness measurement confirmed that the extent of work hardening depends on destabilizing treatments. This study is expected to help the practicing engineers to improve life cycle of high-chromium cast iron components prone to wear.

Highly stable CdS quantum dots embedded in glasses and its application for inhibition of bacterial colonies

An inhibition of pathogenic bacteria using light source is an attractive phenomenon. The present study is based on the application of CdS quantum dots (QDs) grown in the glass matrix for growth inhibition of bacteria. Glass system 36SiO2–15B2O3–15Na2O–9K2O–25ZnO with 3 wt % CdS was prepared by the melt-quench technique. CdS QDs were grown in glass matrix with single-step heat treatment and characterized by XRD, HRTEM, XPS, and micro-Raman for phase identification. Their size related to quantum confinement properties were studied with optical absorption (UV–Vis), photoluminescence (PL) spectroscopy. The structural and optical studies confirm the growth of CdS QDs in a glass matrix which was then utilized for antimicrobial activity. The generation and recombination of electron-hole pairs by CdS QDs due to absorption of light were responsible for the formation of reactive oxygen species (ROS). The use of these ROS in bacterial colonies inhibition has been discussed.