Crystal Morphology Research Articles

Effect of Cubic Crystal Morphology on Thermal Characteristics and Mechanical Sensitivity of PYX

To investigate the influence of the cubic crystal morphology on the thermal properties and sensitivity of 2,6-bis(picrylamino)-3,5-dinitropyridine (PYX), cubic PYX (CPYX) crystals were prepared using the antisolvent method. Scanning electron microscopy (SEM), laser particle size analysis, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the morphology, particle size and structure of the prepared products. The thermal behavior, thermal decomposition kinetics, thermal safety parameters and thermal decomposition mechanism of CPYX were investigated by differential scanning calorimetry–thermogravimetry–mass spectrometry–Fourier transform infrared spectrometry (DSC-TG-MS-FT-IR) and in situ FT-IR experiments. Meanwhile, the mechanical sensitivity of CPYX was determined by means of the explosion probability method. The results showed that the product had a smooth cubic morphology and small crystal aspect ratio with an average particle size (d50) of 10.65 μm, but it had no distinct differences from the crystal structure of raw PYX (RPYX). The thermal decomposition peak temperature, the self-accelerating decomposition temperature and the critical temperature of the thermal explosion of CPYX increased by 7.2 °C, 6.1 °C and 10.4 °C, respectively, compared to RPYX. Similarly, the apparent activation energy increased by 15%. Besides these, the impact sensitivity and friction sensitivity of CPYX decreased by 36% and 20%, respectively, compared to RPYX. The decomposition process of CPYX contains two stages. The first stage involves the breakage of N-H bonds and -NO2 groups with the release of CO2, N2O, NO, HCN and H2O, followed by the thermal decomposition of the resulting intermediate and the release of CO2, N2O and HCN in the second stage.

Efficient Synthesis, Characterization, and DFT Calculation of 4,4’-Azo-1,2,4-triazole

ABSTRACT 4,4’-Azo-1,2,4-triazole (atrz) is a new high nitrogen energetic material with high energy density, high gas yield and wide application prospects, but the low synthesis temperature and long time are the main reasons limiting its application. To achieve efficient synthesis of atrz, the double drop synthesis method was designed to solve the problem of unstable concentration of oxidant (HClO) due to batch feeding. The reaction temperature, reaction time, and molar ratio of reactants of n(4-amino-1,2,4-triazole):n(ClO−) were studied and optimized using the single factor variable method; Characterization and analysis of atrz using theoretical calculations with elemental analysis, infrared spectroscopy, crystal morphology, and nuclear magnetic resonance; The thermal properties and stability of atrz were tested and analyzed using TG-DTA. The results showed that the reaction time of the double drop synthesis method was shortened from 5 hours to 1.5 hours under the conditions of similar yield, and the efficiency was increased by 2.3 times. The optimized process was a reaction temperature of 5°C-10°C, reaction time of 1.5 hours, n(4-amino-1,2,4-triazole):n(ClO−) of 1:2, and the yield reached 73%. The product was white, needle-like crystals, which were determined to be atrz by means of characterization and theoretical calculations. Atrz’s decomposition peak temperature is 309.0°C, and when the temperature is below 271.7°C, atrz is thermally stable. The activation energies of atrz calculated by Kissinger and Flynn-Wall-Ozawa methods were 195.0 kJ·mol−1 and 194.6 kJ·mol−1.

Mesoporous SnO2-modified electrode for electrochemical detection of luteolin

Conventional methods like chromatography and spectroscopic analysis have limitations in detecting luteolin. However, electrochemical detection shows promise for reliable analysis. In this study, we compared two different morphologies of SnO2 with the same crystal structure for luteolin detection and found that crystal morphology significantly impacts the catalytic reaction. Compared to SnO2 quantum dots (SnO2 QDs), mesoporous SnO2 (m-SnO2) exhibited a larger specific surface area, providing more active sites for oxidation and reduction reactions. Moreover, m-SnO2 had lower impedance, effectively accelerating charge transfer at the electrode surface. Based on these excellent characteristics, m-SnO2/GCE modified electrode demonstrated outstanding performance in detecting luteolin, achieving a sensitivity of 8.5 μA μM-1, a low limit of 0.19 nM and a wide linear range from 0.5 nM to 1,400 nM. Besides, the m-SnO2/GC electrode displayed excellent consistency, reproducibility, durability, repeatability and specificity. Even three-week exposure to atmospheric conditions, the DPV signal stood at 94.1 % of its original peak current. Those enables its excellent application in practical sample detection. This research enhances our understanding of the influence of material structure and interface on catalytic luteolin detection, providing a theoretical foundation for accurate detection in complex systems. These findings should contribute to the development of more efficient, sensitive, and reliable luteolin sensors.

Enhanced hydrogen storage performance of zinc and magnesium cobaltite nanocomposites

Renewable and sustainable energies are vital for the near future. Hydrogen, as a clean energy carrier, is a potential candidate for supplying energy in the foreseeable future. Nowadays, hydrogen storage technology has become a significant issue in the energy sector. In this study, ZnCo2O4/ZnO and MgCo2O4/MgO nanocomposites have been synthesized using the sol-gel method with stearic acid as a complexing agent. Different analyses were studied to examine the crystal structure, morphology, and physical properties of the as-prepared samples, including X-ray diffraction (XRD), Fourier transforms infrared (FT-IR), field emission scanning electron microscopy (FESEM), diffuse reflectance spectroscopy (DRS), and vibrating sample magnetometer (VSM). Various methods have been utilized for hydrogen storage technology. In a pioneering approach, the electrochemical hydrogen storage of samples was compared by the chronopotentiometry technique in KOH (4 M) electrolyte solution. The results reveal that ZnCo2O4/ZnO and MgCo2O4/MgO nanocomposites exhibit excellent discharge capacities of 4240 and 3529 mAh/g, respectively, after 11 cycles.

Hybrid Single Crystals of Poly(ε‐caprolactone) Homopolymers and Poly(ε‐caprolactone)‐b‐Poly(ethylene oxide) Block Copolymers

AbstractHybrid single crystals (HSCs) of different poly(ε‐caprolactone) (PCL) homopolymers with a poly(ε‐caprolactone)‐b‐poly(ethylene oxide) (PCL‐b‐PEO) block copolymer (BCP) were prepared. The effects of PCL length, PCL/PCL‐b‐PEO molar ratio, crystallization temperature (Tc) and solvent on crystal morphology were investigated. The optimal Tc for the formation of more perfect HSCs is between those for homo‐crystals of individual PCL and PCL‐b‐PEO and roughly increases with the length of PCL and PCL/PCL‐b‐PEO molar ratio. The chain folding in the HSCs was studied by comparing the experimentally measured heights obtained by atomic force microscopy (AFM) and theoretically calculated ones based on a sandwich structure model. Under most situations, the PCL homopolymers adopt a larger chain folding number in the HSCs than that in their homo‐crystals, while the chain folding of BCP remains unaltered. However, when both PCL homopolymer and PCL‐b‐PEO BCP crystallize slowly and the overcrowding of the PEO is effectively alleviated, thicker HSCs can be formed, in which the PCL homopolymer preserves the chain folding in its homo‐crystals but the BCP adopts a reduced chain folding number as compared with that in its homo‐crystals. The relative crystallization rate of PCL homopolymer versus BCP also affects the real composition and overall height of the HSCs.This article is protected by copyright. All rights reserved

Shape Dependence of Photoresponsive Molecular Crystals Composed of Naphthyl Acrylic Acid Stimulated by Solid-State [2 + 2] Photocycloaddition

Photomechanical molecular crystals, actuated by solid-state photochemical reactions, manifest a spectrum of mechanical motions upon light exposure, underscoring their prospective integration into the next generation of intelligent materials and devices. Utilizing the solid-state photodimerization of naphthyl acrylic acid as a paradigm, this study delved into the interplay between crystal morphology and reaction dynamics on the photomechanical responses of molecular crystals. Distinct crystal forms—bulk, microrods, and microplates—were cultivated through tailored crystallization conditions. While bulk crystals of naphthyl acrylic acid (NA) underwent shattering and splintering upon UV light exposure, the microplate counterparts displayed unique cracking patterns with fissures yet retained their overall structural integrity. In contrast, NA microrods underwent pronounced bending under identical irradiation conditions. These phenomena are attributed to the efficient lattice reconfiguration stemming from the [2 + 2] cycloaddition photochemical reaction within the crystals. An intermediate fluorescence enhancement was observed across all crystal types upon light exposure. Collectively, our results underscore the pivotal role of crystal shape in dictating photomechanical behavior, thereby heralding novel strategies for developing advanced photomechanical materials.

Studies of the Crystallization and Dissolution of Individual Suspended Sodium Chloride Aerosol Particles.

Aerosols transform between physical phases, as they respond to variations in environmental conditions. There are many industries that depend on these dynamic processes of crystallization and dissolution. Here, a single particle technique (an electrodynamic balance) is used to explore the crystallization and dissolution dynamics of a model system, sodium chloride. The physical and environmental factors that influence the dynamics of crystal formation from a saline droplet (whose initial radius is ∼25 μm) and the kinetics of water adsorption onto dried particles are examined. The drying relative humidity (RH) is shown to impact the physical properties of the dried particle. When a saline droplet is injected into an airflow at an RH close to the efflorescence RH (ERH, 45%), an individual single crystal forms. By contrast, when a compositionally equivalent saline droplet is injected into dry air (RH ∼ 0%), a salt crystal made of multiple crystalline particles is formed. Subsequent to crystallization, the crystal shape, morphology, and surface area were all found to affect the dissolution dynamics of the dried particle. Additionally, we report that the difference between the deliquesce RH and environmental RH significantly impacts the dissolution time scale.

Crystal Morphology Prediction Models and Regulating Methods

Crystal Morphology Prediction Models and Regulating Methods

Sn-doped β-Ga2O3 thin films grown on off-axis sapphire substrates by LPCVD using Ga-Sn alloy solid source

Abstract Adopting low pressure chemical vapor deposition (LPCVD), Sn-doped β-Ga2O3 thin films were heteroepitaxially grown on c-plane sapphire substrates with off-axis angles towards <11-20> direction. The influences of off-axis angle on crystal structures, electrical properties, surface morphology, and chemical compositions were thoroughly investigated. As a result, the crystallinity of the β-Ga2O3 films is improved with increasing off-axis angles because in-plane rotational domains are effectively suppressed, demonstrating a full width at half maximum (FWHM) down to 0.64°. Correspondingly, the Hall carrier mobility is promoted from 4.7 to 17.9 cm2/V∙s at carrier concentration of 9×1017 cm-3, which is believed highly competitive among reported Sn-doped β-Ga2O3 films by LPCVD. These results demonstrate an alternative pathway to heteroepitaxially grow high electrical quality n-doped β-Ga2O3 films for the advancement of Ga2O3 materials and devices.

Effect of Fluorine and Phosphorus Impurities in Phosphogypsum on Microstructure and Mechanism of α‐Type Hemihydrate Gypsum Crystals

AbstractIn this study, phosphogypsum (PG) is simulated by doping fluorine and phosphorus ions in an analytically pure reagent of gypsum dihydrate. The influence of fluorine and phosphorus impurity and content on the dehydration reaction process of phosphogypsum and its crystalline micromorphology is assessed during the preparation of α‐type gypsum hemihydrate in the reversed‐phase microemulsion system and its mechanism. The results show that when the fluorine content increases from 0 to 1.0 mol L−1 (ωNaF = 1.0 mol L−1), the dehydration process of dihydrate gypsum will be greatly slowed down. Scanning electron microscopy (SEM) analysis showed that even a small amount of F− (ωNaF = 0.2 mol L−1) can significantly inhibit the formation of α‐type hemi‐hydrated gypsum. When ωH3PO4 = 0.10 mol L−1, the water of crystallization content in the solid phase of the sample decreased to 5.24% after 90 min, which is significantly lower than during the same period of the benchmark group. However, there is a threshold value for the effect of phosphorus on the microscopic morphology of the α‐type gypsum hemihydrate crystals, when ωH3PO4 ≤ 0.04 mol L−1, the crystal morphology is basically unaffected. Moreover, when ωH3PO4 continued to increase, the defects on the crystal surface increased.

Changes in crystal morphology induced by lanthanide doping into diacetylene lamellar crystals

AbstractIn this study, we show that doping lanthanides into lamellar crystals reorganizes the lamellar structure and dramatically changes the crystal morphology. Azo-DA, a compound with azobenzene derivatives and carboxylic acids at both ends of the diacetylene moiety, formed plate-like lamellar crystals. The doping of holmium (Ho), a lanthanide, into the film obtained by stacking Azo-DA lamellar crystals, promoted a dramatic change in crystal morphology, resulting in the formation of an Azo-DA/Ho film with a radial lamellar crystal structure. A detailed investigation of the crystal growth process revealed that Azo-DA/Ho, which is slightly formed in the solution phase during Ho doping, acts as a pseudonucleating agent and dramatically changes the morphology of the lamellar crystals. Additionally, the morphological changes in the lamellar crystal films significantly changed the surface properties of the films, such as their appearance and water repellency. Similar morphological changes in lamellar crystals were induced when other lanthanide elements were used instead of Ho, and the type of lanthanide dopant can affect the magnetic properties of the films.

Crystal structure, composition and valence state of cations in mixed-valence A1-xCdxMnO3 (A=Pr, La) ceramics

Abstract Complex manganites A1-xCdxMnO3 (A=Pr, La) are synthesized by solid state reaction method. Xray diffraction, scanning electron microscopy, and energy-dispersive analysis are applied to study their crystal structure, surface morphology, elemental and phase composition. X-ray photoelectron spectroscopy (XPS) methods are used to study the charge states of Pr and La cations, as well as to quantify the fractions of coexisting Mn3+ and Mn4+ ions. La3d-, La4d-, Pr4d- и Mn2p-spectra of ions La3+, Pr3+, Mn3+ and Mn4+ are calculated in the isolated–ion approximation with accounting for multiplet splitting and charge transfer effect. Good agreement with the experiment is obtained. The relative fractions of trivalent and tetravalent manganese ions in La0.45Cd0.78Mn0,9O2.86 and Pr0.49Cd0.74Mn0.85O2.91 are determined by fitting the Mn2p spectra by the superpositions of experimental spectra containing only Mn3+ and only Mn4+ ions; they were found to be 0.71Mn3+/0.29Mn4+ and 0.54Mn3+/0.46Mn4+, respectively.

Uranium Oxide Hydrate Frameworks with Dy(III) or Lu(III) Ions: Insights Into the Framework Structures With Lanthanide Ions.

Two uranium oxide hydrate frameworks (UOHFs) with either Dy3+ or Lu3+ ions, Dy1.36(H2O)6[(UO2)10UO13(OH)4] (UOHF-Dy) or Lu2(H2O)8[(UO2)10UO14(OH)3] (UOHF-Lu), were synthesized hydrothermally and characterized with a range of structural and spectroscopic techniques. Although SEM-EDS analysis confirmed the same atomic ratio of ~5.5 for U : Dy and U : Lu, they displayed different crystal morphologies, needles for UOHF-Dy in the orthorhombic C2221 space group and plates for UOHF-Lu in the triclinic P-1 space group. Both frameworks are composed of β-U3O8 type layers linked by pentagonal bipyramidal uranium polyhedra, with the Dy3+/Lu3+ ions inside the channels. However, the arrangements of Dy3+/Lu3+ ions are different, with disordered Dy3+ ions well aligned at the centers of the channels and single Lu3+ ions well-separated in a zigzag pattern in the channels. While the characteristic vibrational modes were revealed by Raman spectroscopy, the presence of a pentavalent uranium center in UOHF-Lu was confirmed with diffuse reflectance spectroscopy. The formation of two types of UOHFs with lanthanide ions, high or low symmetry, and the structure trend were discussed regards to synthesis conditions and lanthanide ionic radius. This work highlights the complex chemistry driving the formation of UOHFs with lanthanide ions and has implications to the spent nuclear fuel under geological disposal.

Cystine Renal Calculi: New Aspects Related to Their Formation and Development.

Background: Crystallization experiments of renal-calculi-forming compounds (calcium oxalate, calcium phosphates, uric acid) are normally performed by monitoring these processes during periods of time similar to the residence of urine inside the kidney. Nevertheless, cystine requires high supersaturation for its crystallization, and most experiments last for longer periods. It must be considered that at high supersaturation, the inhibitors of crystalline development have poor effects. Methods: The induction time of crystallization (ti) of cystine in experimental conditions similar to those of the formation of cystine renal calculi and the effect of different cystine-binding thiol agents was determined through turbidimetric measurements. We also studied the macro- and microstructure of 30 cystine kidney stones through stereoscopic microscopy and scanning electron microscopy. Results: Under the studied conditions, the ti in absence of crystallization inhibitors was 15 min, and the presence of 9 mM of penicillamine, tiopronin, or N-acetylcysteine totally inhibited crystallization, as their effects relate to the formation of complexes with cystine, although N-acetylcysteine also delayed cystine crystalline development and modified cystine crystal morphology. Cystine stones have traditionally been classified as smooth and rough. The study of their structure shows that all of them begin their formation from a few crystals that generate a compact radial structure. Their subsequent growth, depending on the renal cavity where they are located, gives rise to the rough structure in the form of large blocks of cystine crystals or the smooth structure with small crystals. Conclusions: To prevent the development of cystine renal stones, the formation of small crystals must be avoided by reducing urinary cystine supersaturation, with N-acetylcysteine being the most effective among the studied cystine-binding thiol agents. Also, the removal of cystine crystals through increased water intake and physical activity can be a very important preventive measure.

Photo-Responsive Hydrogen-Bonded Molecular Networks Capable of Retaining Crystalline Periodicity after Isomerization.

The molecular conformation, crystalline morphology, and properties of photochromic organic crystals can be controlled through photoirradiation, making them promising candidates for functional organic materials. However, photochromic porous molecular crystals with a networked framework structure are rare due to the difficulty in maintaining space that allows for photo-induced molecular motion in the crystalline state. This study describes a photo-responsive single crystal based on hydrogen-bonded (H-bonded) network of dihydrodimethylbenzo[e]pyrene derivative 4BDHP. A crystal composed of H-bonded undulate layers, 4BDHP-2, underwent photo-isomerization in the crystalline state due to loose stacking of the layers. Particularly, enantio-pure crystal (S,S)-4BDHP-2 allowed to reveal the structure of the photoisomerized crystal, in which the closed form (4BDHP) and open form (4CPD) were arranged alternately with keeping crystalline periodicity, although side reactions were also implied. The present proof-of-concept system of a photochromic framework that retains crystalline periodicity after photo-isomerization may provide new light-driven porous functional materials.

Photo‐Responsive Hydrogen‐Bonded Molecular Networks Capable of Retaining Crystalline Periodicity after Isomerization

AbstractThe molecular conformation, crystalline morphology, and properties of photochromic organic crystals can be controlled through photoirradiation, making them promising candidates for functional organic materials. However, photochromic porous molecular crystals with a networked framework structure are rare due to the difficulty in maintaining space that allows for photo‐induced molecular motion in the crystalline state. This study describes a photo‐responsive single crystal based on hydrogen‐bonded (H‐bonded) network of dihydrodimethylbenzo[e]pyrene derivative 4BDHP. A crystal composed of H‐bonded undulate layers, 4BDHP‐2, underwent photo‐isomerization in the crystalline state due to loose stacking of the layers. Particularly, enantio‐pure crystal (S,S)‐4BDHP‐2 allowed to reveal the structure of the photoisomerized crystal, in which the closed form (4BDHP) and open form (4CPD) were arranged alternately with keeping crystalline periodicity, although side reactions were also implied. The present proof‐of‐concept system of a photochromic framework that retains crystalline periodicity after photo‐isomerization may provide new light‐driven porous functional materials.

Multivariate Bayesian Optimization of CoO Nanoparticles for CO2 Hydrogenation Catalysis.

The hydrogenation of CO2 holds promise for transforming the production of renewable fuels and chemicals. However, the challenge lies in developing robust and selective catalysts for this process. Transition metal oxide catalysts, particularly cobalt oxide, have shown potential for CO2 hydrogenation, with performance heavily reliant on crystal phase and morphology. Achieving precise control over these catalyst attributes through colloidal nanoparticle synthesis could pave the way for catalyst and process advancement. Yet, navigating the complexities of colloidal nanoparticle syntheses, governed by numerous input variables, poses a significant challenge in systematically controlling resultant catalyst features. We present a multivariate Bayesian optimization, coupled with a data-driven classifier, to map the synthetic design space for colloidal CoO nanoparticles and simultaneously optimize them for multiple catalytically relevant features within a target crystalline phase. The optimized experimental conditions yielded small, phase-pure rock salt CoO nanoparticles of uniform size and shape. These optimized nanoparticles were then supported on SiO2 and assessed for thermocatalytic CO2 hydrogenation against larger, polydisperse CoO nanoparticles on SiO2 and a conventionally prepared catalyst. The optimized CoO/SiO2 catalyst consistently exhibited higher activity and CH4 selectivity (ca. 98%) across various pretreatment reduction temperatures as compared to the other catalysts. This remarkable performance was attributed to particle stability and consistent H* surface coverage, even after undergoing the highest temperature reduction, achieving a more stable catalytic species that resists sintering and carbon occlusion.

Mo-doping modulated cationic vacancy in Zn3V2O8 with enhanced electrochemical performance for lithium-ion batteries

Given diverse redox reactions and abundant raw materials, Zn3V2O8 with high specific capacity is considered as a potential anode material for lithium-ion batteries. Same as other transition metal oxides, Zn3V2O8 suffers from infertile conductivity, sluggish ion diffusion and fast capacity loss derived from volume expansion during discharge/charge process, further hindering its application. In this work, a novel Mo doped Zn3V2O8 (Zn3V2-xMo5x/6O8) anode material with cationic vacancy (V vacancy) has been designed through a facile sol-gel method. It is found that a small Mo-doping amount has nearly no influence on the crystal structure, morphology and element valence states of Zn3V2O8. Mo doped Zn3V2O8 samples possess smaller charge transfer resistance and higher lithium ion diffusion coefficient. The results of electrochemical performance illustrate that Mo doped Zn3V2O8 can deliver higher reversible specific capacities and better rate capability compared with Zn3V2O8, which can be ascribed to the introduction of V vacancy. In particular, when Mo-doping amount is set as 0.03, the obtained Zn3V1.97Mo0.025O8 exhibits a reversible capacity of 481.1 mAh g−1 after 600 cycles at 1 A g−1. It is believed that this work could provide an effective and feasible strategy to construct high performance transition metal vanadate anode materials for lithium-ion batteries.

MOF-Derived ZrO2-Supported Bimetallic Pd-Ni Catalyst for Selective Hydrogenation of 1,3-Butadiene.

A series of MOF-derived ZrO2-supported Pd-Ni bimetallic catalysts (PdNi/UiO-67-CTAB(n)-A500) were prepared by co-impregnation and pyrolysis at 500 °C under air atmosphere using UiO-67-CTAB(n) (CTAB: cetyltrimethylammonium bromide; n: the concentration of CTAB; n = 0, 3, 8, 13, 18) as a sacrificial template. The catalytic activity of PdNi/UiO-66-CTAB(n)-A500 in 1,3-butadiene hydrogenation was found to be dependent on the crystal morphology of the UiO-67 template. The highest activity was observed over the PdNi/UiO-67-CTAB(3)-A500 catalyst which was synthesized using UiO-67-CTAB(3) with uniform octahedral morphology as the template for the 1,3-butadiene selective hydrogenation. The 1,3-butadiene conversion and total butene selectivity were 98.4% and 44.8% at 40 °C within 1 h for the PdNi/UiO-67-CTAB(3)-A500 catalyst, respectively. The catalyst of PdNi/UiO-67-CTAB(3)-A500 can be regenerated in flowing N2 at 200 °C. Carbon deposited on the surface of the catalyst was the main reason for its deactivation. This work is valuable for the high-efficiency bimetallic catalyst's development on the selective hydrogenation of 1,3-butadiene.

Hierarchically, Low Band Gap Nanohybrid InVO4-CdS Heterojunction for Visible Light-Driven Toxic Organic Dye Degradations.

The synthesis of InVO4-CdS heterojunction photocatalysts has been achieved by a novel two-step approach, including a microwave-assisted technique, followed by a moderate hydrothermal method, marking the first successful instance of such a synthesis. X-ray diffraction, field-emission scanning electron microscopy, elemental color mapping, high-resolution transmission electron microscopy, UV-vis diffuse reflectance spectroscopy, Raman analysis, photoluminescence, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller were employed to investigate the crystal structures, surface morphologies and particle sizes, chemical compositions, and optical characteristics of the as-synthesized materials. The research results indicated that the heterojunction InVO4-CdS, as synthesized, consisted of InVO4 microrods with an average size of around 15 nm and cadmium sulfide (CdS) microflowers with a diameter of 1.5 μm. Furthermore, all of the heterojunctions had favorable photoabsorption properties throughout the visible-light spectrum. The photocatalytic efficiency of the samples obtained was thoroughly assessed by the degradation of acid violet 7 (AV 7) under visible light irradiation with a wavelength greater than 420 nm. The photocatalytic efficiency for the decomposition of AV 7 was greatly enhanced in the InVO4-CdS (IVCS) heterojunctions when compared to prepared bare InVO4 and CdS. Additionally, it was observed that the composite material consisting of IVCS 3 wt % InVO4 combined with CdS exhibited the most significant enhancement in catalytic effectiveness for the photodegradation of AV 7 dye. Specifically, the catalytic performance of this composite material was found to be around 69.4 and 76.2 times greater than that of pure InVO4 and CdS, respectively. Furthermore, the experimental procedure including active species trapping provided evidence that h+ and •O2- radicals were the primary active species involved in the photocatalytic reaction process. Additionally, a potential explanation for the improved photocatalytic activity of the InVO4-CdS heterojunction was presented, taking into account the determination of band positions.