Dioctyl Sulfosuccinate Sodium Salt Research Articles

Synthesis of PDMS Chain Structure with Introduced Dynamic Covalent Bonding for High‐Performance Rehealable Tactile Sensor Application

AbstractIn addressing the increasing demand for wearable sensing systems, the performance and lifespan of such devices must be improved by enhancing their sensitivity and healing capabilities. The present work introduces an innovative method for synthesizing a healable disulfide bond contained in a polydimethylsiloxane network (PDMS−SS) that incorporates ionic salts, which is designed to serve as a highly effective dielectric layer for capacitive tactile sensors. Within the polymer network structure, the cross‐linking agent pentaerythritol tetrakis 3‐mercaptopropionate (PTKPM) forms reversible disulfide bonds while simultaneously increasing polymer softness and the dielectric constant. The incorporation of dioctyl sulfosuccinate sodium salt (DOSS) significantly improves the capacitance and sensing properties by forming an electrical double‐layer through interactions between the electrode charge and salt ions at the contact interface. The developed polymer material‐based tactile sensor shows a strong response signal at low pressure (0.1 kPa) and maintains high sensitivity (0.175 kPa−1) over a wide pressure range (0.1–10 kPa). It also maintains the same sensitivity over 10 000 repeated applications of external pressure and is easily self‐healed against mechanical deformation due to the dynamic disulfide covalent bonding, restoring ≈95% of its detection capacity.

Enhancing the tribological performance of PLA-based biocomposites reinforced with graphene oxide

Poly(lactic acid) (PLA) reinforced with graphene has gained substantial interest as a biomaterial, where the tribological and mechanical behavior of PLA/graphene composites are major concerns. This study aims to develop PLA-based biocomposites reinforced with graphene oxide (GO) that have enhanced tribological capabilities. First, homogenous dispersions of GO and GO treated with the anionic surfactant dioctyl sulfosuccinate sodium salt (AOT) were retained. Then, poly(L-lactic acid) (PLLA) biopolymer and PLLA/GO, PLLA/GO(AOT), PLA/GO(AOT), and PLLA/polyethylene glycol (PEG)/GO biocomposite samples were produced via hot pressing, and their tribological behavior was examined in detail. The worn surface characteristics were examined using scanning electron microscopy (SEM), 3D confocal microscopy, and atomic force microscopy (AFM). Results showed that GO reinforcement considerably affected the sliding wear behavior of PLA. Contrary to anticipated, surface treatment of GO does not improve the PLLA/GO wear resistance; rather, it increases the wear rate. PEG positively affects the sliding wear performance of PLLA/GO. PLLA/GO and PLLA/PEG/GO biocomposites exhibited the lowest wear rate at normal loads of 5 and 8 N, respectively, which was decreased by about 50% compared to unreinforced PLLA samples. With the addition of GO, the wear mechanisms of the PLA-based biocomposites changed from adhesive wear to abrasive wear. These findings might increase the applicability of PLA-based biocomposites where tribological performance is the main concern, such as biodegradable implants for load-bearing bone fractures or scaffolds, opening up new opportunities for their use.

Effect of adjuvants on physicochemical properties of lime sulfur on flower/paraffin and application on flower thinning.

Adjuvants can effectively enhance the utilization rate of pesticides, but the application of adjuvants in plant growth regulators is rarely studied. This work explored the effects of adjuvants dioctyl sulfosuccinate sodium salt (AOT) and methyl oleate (MO) on lime sulfur (LS), especially the drop behavior on flower and paraffin surface. The results showed that the addition of AOT and AOT+MO can significantly reduce the static and dynamic surface tension of LS from 72mN/m to 28mN/m and 32mN/m respectively, and increase the spreading factor from 0.18 to 1.83 and 3.10 respectively, reduce the bounce factor from 2.72 to 0.37 and 0.27 respectively. The fluorescence tracer test showed that the addition of adjuvants could promote the spreading and permeation of droplets. The field test results revealed that the flower thinning rate of adjuvant and non-adjuvant were 80.55% and 54.4% respectively, and the flower thinning effect of adding adjuvant was the same as that of artificial which the flower thinning rate was 84.77%. The quality of apples treated with adjuvants was similar to that treated with artificial, and the weight of single fruit increased by 24.08% compared with CK (spray water). The application of tank-mixture adjuvant could reduce the dosage of LS for thinning agent application, improve apple's quality, and decrease labor cost and improve the economic benefits of fruit planting and the environmental benefits of plant growth regulators.

Enhancing Structural and Thermal Properties of Poly(lactic acid) Using Graphene Oxide Filler and Anionic Surfactant Treatment.

Graphene has attracted extensive attention in various fields due to its intriguing properties. In this work, nanocomposite films based on poly(lactic acid) (PLA and PLLA) polymers filled with graphene oxide (GO) were developed. The impact of treating GO with the anionic surfactant dioctyl sulfosuccinate sodium salt (AOT) on the properties of the resulting nanocomposites was investigated. To determine the morphological, optical, and structural properties of the obtained materials, physicochemical analyses were performed, including scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) analysis. Additionally, the thermal properties and wettability of neat polymers and nanocomposites were thoroughly investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and contact angle analysis. It was observed that GO was well dispersed throughout the PLA and PLLA matrix, leading to stronger interface bonding. The results demonstrate that the untreated and treated GO improved the crystallinity and thermal stability properties of the PLA and PLLA. However, the AOT-treated GO has significantly higher performance compared to the untreated GO in terms of crystallinity, melting temperature (increased by ~15 °C), and wettability (the contact angle decreased by ~30°). These findings reveal the high performance of the developed novel composite, which could be applied in tissue engineering as a scaffold.

The loss of crude oil droplets by filter feeders and the role of surfactants

Various methods of oil spill remediation exist, e.g., floating booms, controlled burning and the release of chemical surfactants. These surfactants facilitate the breakup of the slick into micron-sized droplets. Here, we studied the impact such a surfactant has on the size distribution of oil droplets in the water column and in the gut of the filter feeder Daphnia magna. We also studied the effect of surfactants on detachment conditions of chemically and mechanically dispersed oil (respectively MDO and CDO) droplets from capture fibers. Our results show that including solubilized dioctyl sulfosuccinate sodium salt in the mixing of the emulsion produces smaller droplets and a narrower size distribution in the water. In the gut, the size of ingested droplets does not change whether the oil is mixed mechanically or chemically. Also, surfactant coated droplets detach at a lower velocity than mechanically dispersed droplet because of their lower oil/water interfacial tension.

Insight in Superiority of the Hydrophobized Gentamycin in Terms of Antibiotics Delivery to Bone Tissue.

Bone infections are a serious problem to cure, as systemic administration of antibiotics is not very effective due to poor bone vascularization. Therefore, many drug delivery systems are investigated to solve this problem. One of the potential solutions is the delivery of antibiotics from poly(L-actide-co-glycolide) (PLGA) nanoparticles suspended in the gellan gum injectable hydrogel. However, the loading capacity and release kinetics of the system based on hydrophilic drugs (e.g., gentamycin) and hydrophobic polymers (e.g., PLGA) may not always be satisfying. To solve this problem, we decided to use hydrophobized gentamycin obtained by ion-pairing with dioctyl sulfosuccinate sodium salt (AOT). Herein, we present a comparison of the PLGA nanoparticles loaded with hydrophobic or hydrophilic gentamycin and suspended in the hydrogel in terms of physicochemical properties, drug loading capacity, release profiles, cytocompatibility, and antibacterial properties. The results showed that hydrophobic gentamycin may be combined in different formulations with the hydrophilic one and is superior in terms of encapsulation efficiency, drug loading, release, and antibacterial efficacy with no negative effect on the NPs morphology or hydrogel features. However, the cytocompatibility of hydrophobic gentamycin might be lower, consequently more extensive study on its biological properties should be provided to evaluate a safe dose.

Evaluation of surfactant blends for enhanced oil recovery through activity maps

Better use of already exploited oil reservoirs using Enhanced Oil Recovery techniques is becoming essential. The use of surfactant blends is a common approach when individual surfactants are not effective. However, defining the optimum conditions for application becomes very challenging due to the number of variables involved in specific cases. In this work, blends of dioctyl sulfosuccinate sodium salt with Akypo LF2 and two surfactant ionic liquids (1-decyl-3-methylimidazolium chloride and 1-dodecyl-3-methylimidazolium bromide) were evaluated for oil recovery. Activity maps, representations of the phase behavior of the surfactants as a function of blend ratio, salinity and temperature, were found to be useful tools to describe conditions leading to Winsor type III systems. Among the blends studied, mixtures with Akypo LF2 were found of interest for application at low temperatures, showing interfacial tensions close to 0.01 mN/m in a wide range of salinity concentrations. In the case of blends with ionic liquids, even though they led to more promising solubilization parameters, the high sensitivity of these mixtures to blend ratio changes discourages, in principle, their use for practical applications.

Low‐Voltage Electrically Responsive Photonic Crystal Based on Weak‐Polar Colloidal System

AbstractElectrically responsive photonic crystal (ERPC) based on particle electrophoresis is a promising material to construct reflective color displays with low‐power‐consumption and antiglare advantages. However, the high driving voltages for the polar ERPC inevitably cause electrochemical reactions on the electrode, which decreases the stability and reversibility of electrical response. Here, a weak‐polar EPRC composed of hydrophobic SiO2 particles, 1,2‐dichlorobenzene (DCB), and dioctyl sulfosuccinate sodium salt (AOT) is fabricated based on the charge separation by AOT reverse micelles and formation of highly charged particles in DCB. Compared to the polar ERPCs, the SiO2/DCB‐AOT ERPC works at much lower voltages (0.5–1.7 V) and still possesses a wide color tuning range because the weak‐polar solvent applies less screening to the coulombic interactions. The low potential further renders the ERPC good capability against color fading in a strong field and long‐term reversibility during color switching, which addresses the critical concerns for its application in reflective displays.

Ultrasound-assisted carboxymethylation of LignoForce Kraft lignin to produce biodispersants

Softwood contains up to 40 wt% of lignin, which makes it the most abundant polyphenolic biopolymer on earth. The applications of Kraft lignin, because of its poor solubility, are not as numerous as other water-soluble lignin derivatives, such as lignosulfonates. We investigated the ultrasound-assisted carboxymethylation of two softwood LignoForce Kraft lignins in sodium hydroxide with sodium chloroacetate (SCA) as the carboxylate group donor to yield a water-soluble product. Thermogravimetric analyzer, gel permeation chromatography, and Fourier-transformed infrared spectroscopy characterized the physico-chemical properties of the carboxymethylated lignins. A photometric dispersion analyzer determined the ability of the carboxymethylated lignin to disperse kaolin clay aqueous suspensions. A SCA/lignin ratio of 12 and ultrasound at 20 W and 20 kHz yielded carboxymethylated lignins with a dispersion ability comparable to dioctyl sulfosuccinate sodium salt, a common dispersant. Ultrasound intensified the process by reducing the reaction time from 4 h (conventional process) to 30 min.

Pulsed Laser Ablation on Polymethylmethacrylate (PMMA) Surfaces for Capillary Driven Flows

Developing a surface modification technique that can be applied to a variety of thermoplastic polymers is of great practical importance. Laser surface treatment is one of effective ways to modify the surface property that can be used for various biomedical applications. In this research, we employed a controllable laser ablation technique on a polymethylmethacrylate (PMMA) surface that can improve the surface wetting property. The ablated hierarchical micro- and nano-structures and surfactant coating of dioctyl sulfosuccinate sodium salt induced controllable capillary driven flows. Morphology and wetting properties of laser ablated PMMA surface have been investigated from the perspective of possible applications in lateral flow assay. We also carried out an experimental investigation on controlling the flow rate and dynamics of capillary driven flow influenced by the ablated surface, channel width, aspect ratio, laser pulse step size, and viscosity of test fluids. While the capillary driven flow was found to follow the modified Lucas-Washburn dynamics, we also observed that the distance of advancing front contact line scaled by the hydraulic radius was inversely proportional to capillary number.

The study of ultralow interfacial tension SiO2-surfactant foam for enhanced oil recovery

Surfactant selection and formulation are key factors in technological and economic success in chemically enhanced oil recovery (cEOR) applications. In this study, the silica nanoparticle (SNP) was added in an ultralow interfacial tension foam (ULIFT), called SNP-ULIFT foam, which was successfully prepared by ternary surfactant systems. The Carboxylate-based extended surfactant (Carboxylate), Dioctyl Sulfosuccinate Sodium salt (AOT), and Sodium Diphenyl Oxide Disulfonate (DODS) at a 0.48:0.48:0.04 wt ratio were conducted as the surfactant system. Remarkable results in the selected surfactant system were observed in terms of the ability to form foaming and ultralow interfacial tension (IFT) at 60 ± 2 °C with the ADNOC crude oil (Abu Dhabi National Oil Company) as model oil. The optimum salinity of the surfactant system was found at 2.5 wt% (8:2 Na:Ca by weight), indicating a minimum IFT of 0.0019 mN/m. The adsorption capacities at the optimum salinity condition of each surfactant in the mixture onto the SNP's surface were 1.4, 7.3 and 19.4 molecule/nm2 for the DODS, Carboxylate and AOT surfactants, respectively; the calculated total surfactant adsorption was 2.6 mg surfactant/mg nanoparticles. While in the presence of SNP, the surfactant adsorption of the ternary surfactant foam system onto the sand surface was significantly reduced by 16.2% at 200 psi and 60 °C when compared with the neat ULIFT foam system. It was remarkably noted that the adsorption of the surfactant onto the SNP surface could result in a reduction of surfactant adsorption onto the sand surface. The oil recovery performance in the core flood by ULIFT foam was the greatest with 43% of Original Oil in Place (OOIP), and it further increased by 13% in the presence of 200 ppm SNP. In addition, the stress and viscosity of ULIFT microemulsion significantly decreased with SNP. This suspension exhibited the most non-Newtonian behavior with shear-thinning behavior over different ranges of shear rate. Therefore, SNP-ULIFT foam with the appropriate surfactant selection was a successful method for improving oil recovery performance.

Thermodynamic study of corrosion inhibition of Dioctylsulfosuccinate Sodium Salt as corrosion inhibitor against mild steel in 1 M HCl

Scanning electron microscopy (SEM) and weight loss studies were performed to determine the corrosion inhibition effectiveness of Dioctylsulfosuccinate Sodium Salt in 1 M HCl against mild steel. The inhibitory effectiveness of Dioctylsulfosuccinate Sodium Salt improves with increasing doses but declines with temperature, reaching 93.32 % at 298 K at 0.67 mM, according to the findings. Langmuir adsorption isotherm was followed by the adsorption mechanism. The thermodynamic parameters such as Kads and ΔG°ads are determined and explained. Scanning electron microscopy (SEM) verified the development of an inhibitor-adsorbed layer on the mild steel (MS) surface. The findings demonstrated that the investigated inhibitor significantly decreased mild steel corrosion in acid environments.

Deaeration of stable coal froth by surfactants to modify the interfacial properties

Overly stable froth is an emerging problem in fuel and mineral processing plants and poses operational and safety concerns. A remedial strategy is not currently available. As a new initiative this study examined three surfactants, dioctyl sulfosuccinate sodium salt (DOSS), sodium dodecylbenzenesulfonate (SDBS) and perfluorooctanoate (PFOA) which vary in both hydrophobic chain and hydrophilic functional group, in deaerating and collapsing overly stable coal froth. The underpinning premise was that an ideal surfactant structure could modify particle surface hydrophobicity and air–liquid interfacial tension in such a way so as to destabilize stable froth. The deaeration tests together with contact angle and interfacial tension measurements indicated that the reduction of contact angle of coal particles played a dominant role in froth deaeration, while the reduction of air–liquid interfacial tension had a negative effect on destabilizing stable froth. The addition of hydrocarbon surfactants DOSS and SDBS could achieve a complete froth deaeration due to their high contents of hydrophilic polar groups and strong adsorption capacity on coal surfaces which could reduce the contact angle of coal particles to near zero. However, PFOA, a fluorocarbon surfactant, could only reduce the contact angle of coal particles moderately and therefore was not effective in deaerating stable coal froth even at a high concentration.

Biocompatible polypeptide nanogel: Effect of surfactants on nanogelation in inverse miniemulsion, in vivo biodistribution and blood clearance evaluation

Horseradish peroxidase (HRP)/H2O2-mediated crosslinking of polypeptides in inverse miniemulsion is a promising approach for the development of next-generation biocompatible and biodegradable nanogels. Herein, we present a fundamental investigation of the effects of three surfactants and their different concentrations on the (HRP)/H2O2-mediated nanogelation of poly[N5-(2-hydroxyethyl)-l-glutamine-ran-N5-propargyl-l-glutamine-ran-N5-(6-aminohexyl)-l-glutamine]-ran-N5-[2-(4-hydroxyphenyl)ethyl)-l-glutamine] (PHEG-Tyr) in inverse miniemulsion. The surfactants sorbitan monooleate (SPAN 80), polyoxyethylenesorbitan trioleate (TWEEN 85), and dioctyl sulfosuccinate sodium salt (AOT) were selected and their influence on the nanogel size, size distribution, and morphology was evaluated. The most effective nanogelation stabilization was achieved with 20 wt% nonionic surfactant SPAN 80. The diameter of the hydrogel nanoparticles was 230 nm (dynamic light scattering, DLS) and was confirmed also by nanoparticle tracking analysis (NTA) which showed the diameters ranging from 200 to 300 nm. Microscopy and image analyses showed that the nanogel in the dry state was spherical in shape and had number-average diameter Dn = 26 nm and dispersity Ð = 1.91. In the frozen-hydrated state, the nanogel appeared porous and was larger in size with Dn = 182 nm and Ð = 1.52. Our results indicated that the nanogelation of the polymer precursor required a higher concentration of surfactant than classical inverse miniemulsion polymerization to ensure effective stabilization. The developed polypeptide nanogel was radiolabeled with 125I, and in vivo biodistribution and blood clearance evaluations were performed. We found that the 125I-labeled nanogel was well-biodistributed in the bloodstream, cleared from mouse blood during 48 h by renal and hepatic pathways and did not provoke any sign of toxic effects.

Unraveling the binding and micellization behavior of dioctylsulfosuccinate Sodium Salt with vitamin B1 and B6: A physiochemical and computational study

The outcomes of drug delivery rely on the route of administration which further depends on the understanding of interactional or partitioning mechanism of drugs within the self assembled structures. Thus, identification of various interactions in such systems is of utmost importance. Herein, the partitioning of vitamins: B1 (thiamine hydrochloride; THC) and B6 (Pyridoxine hydrochloride; PyH) in dioctyl sulfosuccinate sodium salt (AOT) have been addressed by employing experimental and computational techniques. The values of partial molar volumes (ΔtrV2,фo) and partial molar isentropic compressions ΔtrKS,2,фo of transfer for PyH have been calculated from density and sound velocity measurements which suggest the presence of hydrophilic interactions between AOT and PyH. The obtained results were further supported by Density Functional Theory Calculations which suggest that hydrogen bonding plays important role in PyH/AOT binding. The binding constants along with thermodynamic parameters at different temperatures have been calculated using calorimetric measurements. In case of THC/AOT the negative values of ΔrS are overcome by more negative values of ΔrH, making the overall process favorable. In case of PyH, two set of binding sites with stronger affinity for second site have been observed along with favorable entropy. Calorimetric and surface tension measurements were used to study the impact of PyH/THC on the Critical micelle concentration of AOT. Spectroscopic and Dynamic light scattering studied have been used as complementary techniques that also confirmed the partitioning of vitamins in AOT micelles.

Influence of Electrolyte and Temperature on the Aggregation Behaviour of Mixed System Consisting Drug and Anionic Surfactant

At present work, the interaction of amphiphilic drug promazine hydrochloride (PMZ) with anionic surfactant sodium dodecyl sulfate (SDS) and imipramine hydrochloride (IMH) with anionic surfactant dioctyl sulfosuccinate sodium salt (AOT) in the absence and presence of 50 mmol.kg−1 inorganic salt is investigated in aqueous medium at different temperatures. For this, conductometric measurements were carried out to evaluate the critical micelle concentrations (CMC) of drug and surfactant. Ideal critical micelle concentration (CMC id) and interaction parameter (β) has also been evaluated. The deviations obtained in values of CMC and CMC id indicate the interaction between drug and surfactant. Other micellar mole fraction parameters such as X1 Rub (Rubingh), X1 Mot (Motomura), X1 Rd (Rodenas) and X1 ideal (ideal mole fraction) are also evaluated based on different proposed models. Other thermodynamic parameters of micellization such as, standard free energy of micellization , standard enthalpy of micellization , and standard entropy of micellization are also evaluated based upon the equations already present in literature to understand the interactions prevailing in the studied systems.

Relaxation of Physicochemical Processes during the Chemical Synthesis of Silver Nanoparticles in Reverse Micellar Solutions

The kinetics of optical properties is studied experimentally on an OT Aerosol (dioctyl sulfosuccinate sodium salt)/isooctane/Qr (quercetin)/Ag+) reverse micellar system (RMS) during the chemical synthesis of Ag nanoparticles. The kinetic light optical absorption data acquired for an RMS at a wavelength λ = 432 nm with a chronometric resolution of 0.14 and 1 s are used to calculate the boundaries of the stages of Ag NP formation (at a confidence factor of at least 0.99). The determination of relaxation times (almost-periods) in an RMS allows evaluation of the kinetics parameters at certain stages of the chemical synthesis of NP metals.

Potential Application of Dioctyl Sodium Sulfosuccinate Salt (DOSS)–Saponin Binary Dispersant in Oil Spill Remediation: Synergistic Interaction Between DOSS and Saponin

The interfacial activity of dispersants can be enhanced by combining two or more surfactants to formulate the dispersant. This paper examines the effects of Bio-Saponin (BS), a phytogenic surfactant on the interfacial activity of synthetic dioctyl sulfosuccinate sodium salt (DOSS) usually adopted as a suitable surface-active agent in dispersants used in dealing with large-scale oil spills. The o/w emulsion created with the binary DOSS-BS was very stable and recorded the least average droplet size compared with that of DOSS only and BS only. Lower surface and interfacial tension values were also obtained from the DOSS-BS binary formulation. The dispersion effectiveness was also higher compared with that of DOSS and BS. However, they were dependent on the salinity and type of crude oil. These observations were attributed to the moderation of the interaction between the anionic head group of DOSS by the polysaccharide hydrophilic group of BS. The results revealed the potential application of DOSS-BS binary dispersant in oil spill remediation and in other processes that would require an effective emulsifier.

Oxygen vacancies in concave cubes Cu2O-reduced graphene oxide heterojunction with enhanced photocatalytic H2 production

A novel composite heterojunction based on concave cubes Cu2O-reduced graphene oxide (Cu2O-RGO) was synthesized via one-pot hydrothermal method. The anionic surfactant dioctyl sulfosuccinate sodium salt (AOT) can act as the soft template to build the novel Cu2O-based microstructure. The ascorbic acid serves as reductant and etching agent in the Cu2O growing process. The facet etching of Cu2O and reduction of GO can take place simultaneously in the reaction system. The concave cubes Cu2O with average edge length of ~ 1.55 µm were well-dispersed on the surface of RGO. The Cu2O-RGO (2 wt%) heterojunction exhibited superior photocatalytic performance and recyclability with the highest amount of H2 yields of 64.3 µmol/g, which was fivefold more than the pure Cu2O (12.8 µmol/g). The enhanced photocatalytic performances were attributed to the oxygen vacancies in Cu2O and a flexible conducting channel supported by RGO. Furthermore, the synergistic effect of Cu2O and graphene caused broader absorption in visible light region and lower recombination of photogenerated electron–hole pairs. It is believed that the Cu2O-RGO heterojunction could provide an alternative method to design excellent photocatalysts for energy application.

Highly enhanced photocatalytic H2 evolution of Cu2O microcube by coupling with TiO2 nanoparticles

A Cu2O/TiO2 p-n heterojunction composite was created via a facile, controllable, one-pot hydrothermal method based on cubic Cu2O and TiO2 nanoparticles in the presence of dioctyl sulfosuccinate sodium salt (AOT) surfactant. The TiO2 nanoparticles with an average edge length of ∼10.1 nm were uniformly distributed on the crystal surface of a Cu2O cube {100}. The photocatalytic performance of the composite was effectively tuned by controlling the amount of TiO2. The Cu2O/TiO2 (60 wt%, labeled as CT-60) exhibits the highest enhanced photocatalytic activity in hydrogen production with H2 evolution of 3002.5 μmol g–1. The yield remained around 92.6% after three cycles. Hydrogen production of the CT-60 is 103 and 8.5 fold higher than the cubic Cu2O and TiO2 nanoparticles, respectively. The improvement in photocatalytic performance could be attributed to the formation of p-n heterojunction. Furthermore, the interface effect of Cu2O and TiO2 caused a broader absorbance in the visible-light region and the lower recombination of photogenerated electron–hole pairs. It is believed that the Cu2O/TiO2 p-n heterojunction composites could provide an alternative method to design highly efficient photocatalysts for solar energy.