Low Power CO2 Laser Research Articles

Fabrication of Microchannels on Aluminium-Coated Polymethyl Methacrylate (PMMA) Using a Low Power CO2 Laser

Fabrication of Microchannels on Aluminium-Coated Polymethyl Methacrylate (PMMA) Using a Low Power CO2 Laser

Optimization of laser beam parameters during processing of ASA 3D-printed plates

AbstractNew developments in manufacturing processes impose the need for experimental studies concerning the determination of beneficial process-related parameter settings and optimization of objectives related to quality and efficiency. This work aims to improve cutting geometry, surface texture, and arithmetic surface roughness average in the case of post-processing of filament material extrusion 3D-printed acrylonitrile styrene acrylate (ASA) thin plates by a low-power CO2 laser cutting apparatus. This material was selected owing to its unique properties for thin-walled customized constructions. Three parameters, namely focal distance, plate thickness, and cutting speed, were examined with reference to the Box-Behnken design of experiments (BBD) and regression modeling. Four responses were considered: mean kerf width, Wm (mm); down width, Wd (mm); upper width, Wu (mm); and average surface roughness Ra (μm) of cut surfaces. Different regression models were tested for their efficiency in terms of predicting the objectives with an emphasis on full quadratic regression. The results showed that a focal distance of 6.5 mm and 16 mm/s speed optimizes all quality metrics for the three plate thicknesses. The regression models achieved adequate correlation among independent process-related parameters and optimization objectives, proving that they can be used to improve the laser cutting process and support practical applications.

Efficacy and Safety of Picosecond Laser in the Treatment of Melasma: A Network Meta-analysis.

The role of lasers in the treatment of melasma and acquired hyperpigmentation disease of the skin has been suggested by clinicians. However, there is no consensus on the most efficient and safe treatment method. To systematically evaluate the efficacy and safety of picosecond laser in the treatment of melasma. PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Chinese scientific journal database, and Wanfang database were searched. The data for therapeutic efficacy, melasma area and severity score, and incidence rate of adverse reactions were extracted from the included studies. A total of 20 studies involving 1,182 patients were included in this network meta-analysis. Combined therapy with carbamic acid and 1064-nm picosecond laser was the best measure. Melasma area and severity index score of patients after low-power fractional CO2 laser treatment was higher than that of patients after the treatment with 1064-nm picosecond laser. Aminomethyl cyclic acid combined with 1064-nm picosecond laser may have the highest effective rate after treatment. Low-power fractional CO2 laser provided the lowest melasma area and severity index score after treatment, and the incidence rate of adverse reactions after treatment, was highest when intense pulsed light was used.

Tranexamic acid versus fractional carbon dioxide laser in post-acne hyperpigmentation.

Post-acne hyperpigmentation is a common undesirable sequela of acne vulgaris that causes distress for many patients. This study's objective was to compare the efficacy of both low-power/low-density fractional carbon dioxide (CO2 ) laser and tranexamic acid (TXA) microinjection on post-acne hyperpigmentation. Twenty-five post-acne hyperpigmentation patients (resistant to regular treatment for more than 6 months) were enrolled in this randomized split-face study. One side of the face was randomly assigned to low-power fractional CO2 laser every 4 weeks, and the other side was assigned to TXA intradermal-microinjection every 2 weeks for 3 months. Efficacy was evaluated using digital photography, dermoscopy, post-acne hyperpigmentation index (PAHPI), melanin index (MI), and erythema index (EI) at baseline and 4 weeks after the last session. Both fractional CO2 laser and TXA microinjection treatment sides showed a significant reduction in the PAHPI and MI (p< 0.001). There was statistically significant difference with better percentage of improvement regarding total dermoscopic score on the fractional CO2 laser side than the TXA microinjections side (p< 0.009). Both fractional CO2 laser and TXA microinjection are effective and safe treatment options for post-acne hyperpigmentation with potential superiority of fractional CO2 laser. We also believe that dermoscopy could be helpful tool for assessment of pigmentation depth in patients on treatment by analyzing the color pattern. ClinicalTrials.govID: NCT03765021.

A Generalised Approach on Kerf Geometry Prediction during CO2 Laser cut of PMMA Thin Plates using Neural Networks

This study presents an application of feedforward and backpropagation neural network (FFBP-NN) for predicting the kerf characteristics, i.e. the kerf width in three different distances from the surface (upper, middle and down) and kerf angle during laser cutting of 4 mm PMMA (polymethyl methacrylate) thin plates. Stand-off distance (SoD: 7, 8 and 9 mm), cutting speed (CS: 8, 13 and 18 mm/sec) and laser power (LP: 82.5, 90 and 97.5 W) are the studied parameters for low power CO2 laser cutting. A three-parameter three-level full factorial array has been used, and twenty-seven (33) cuts are performed. Subsequently, the upper, middle and down kerf widths (Wu, Wm and Wd) and the kerf angle (KA) were measured and analysed through ANOM (analysis of means), ANOVA (analysis of variances) and interaction plots. The statistical analysis highlighted that linear modelling is insufficient for the precise prediction of kerf characteristics. An FFBP-NN was developed, trained, validated and generalised for the accurate prediction of the kerf geometry. The FFBP-NN achieved an R-all value of 0.98, in contrast to the ANOVA linear models, which achieved Rsq values of about 0.86. According to the ANOM plots, the parameter values which optimize the KA resulting in positive values close to zero degrees were the 7 mm SoD, 8 mm/s CS and 97.5 W LP.

ON THE POSSIBILITY OF LASER STRIPPING OF COMMUNICATION CABLES WITH LOW-POWER CO2 LASER

Laser engraving is one of the most commonly used laser procedures for interacting with laser material. The speed, ease of use and high precision make it an attractive process for use by manufacturers and for removing insulation from various cables. Cable stripping is a particularly common operation in aeronautics. The aircraft is equipped with several hundred kilometers of cables to control and operate the various systems of the aircraft and most of these cables must be stripped at both opposite ends to allow the cable to be connected to different terminals.This report examines the possibility of removing polyvinyl chloride (PVC) insulation from telecommunication cables of different colours and thicknesses up to 600 [μm]. The experimental measurements of the study were performed with a low-power continuous CO2 laser system. The main functional dependence of the width and depth of the ablation zone on the main technological parameters, such as the average power and the processing speed, have been experimentally studied. The zones of laser impact are observed with a laser microscope. The graphic dependencies are analyzed in order to determine the optimal working intervals.The analysis aims to help solve problems related to the application of small diameter communication cables in the production of various communication devices and components for the needs of industry.

Clinical observation and dermoscopy evaluation of fractional CO2 laser combined with topical tranexamic acid in melasma treatments.

Melasma is an acquired refractory pigmentary disorder, which is a skin disease that predominantly affects females. This investigation aims to assess the efficacy of a low-power fractional CO2 laser combined with tranexamic acid (TXA) for melasma topical treatment with MASI and dermoscopy. A randomized comparative split-face study was performed. Each treatment interval was 3 weeks with four times in total. At the same time, we applied TXA solution twice a day. Assessments were made by the MASI score of the melasma area severity index, and the dermoscopy performance was collected and analyzed. After treatments, the patient MASI score decreased significantly. Compared with the baseline, the MASI score was significantly lower than that of control group (P<.05), and the decrease ratio was higher than that of controls. Dermoscopy examination results verified that all lesions performed reticuloglobular pattern, granular, or punctate, with no structural pigmentation and obvious capillary dilation. After comprehensive treatments, the pigmentation area displayed lighter chroma, the follicle pore uniformity was completely improved, and the capillary dilation was significantly reduced. Low-power fractional CO2 laser combined with topical TXA solution is a comparatively effective and safe method for melasma treatment. TXA could reduce the dilation of blood vessels.

Optimization of Parameters for the Cutting of Wood-Based Materials by a CO2 Laser

This article deals with the laser cutting of wood and wood composites. The laser cutting of wood and wood composites is widely accepted and used by the wood industry (due to its many advantages compared to, e.g., saw cutting). The goal of this research was to optimize the cutting parameters of spruce wood (Pices abies L.) by a low-power CO2 laser. The influence of three factors was investigated, namely, the effect of the laser power (100 and 150 W), cutting speed (3, 6, and 9 mm·s−1), and number of annual rings (3–11) on the width of the cutting kerf on the top board, on the width of the cutting kerf on the bottom board, on the ratio of the cutting kerf width on the top and bottom of the board, on the width of the heat-affected area on both sides of the cutting kerf (this applies to the top and bottom of the board), and on the degree of charring. Analysis of variance (ANOVA) and correlation and regression analysis were used for developing a linear regression model without interactions and a quadratic regression model with quadratic interactions. Based on the developed models, the optimization of parameter settings of the investigated process was performed in order to achieve the final kerf quality. The improvement in the quality of the part ranged from 3% to more than 30%. The results were compared with other research dealing with the laser cutting of wood and wood composites.

Fractional-Pixel CO2 Laser Treatment in Patients With Urodynamic Stress Urinary Incontinence: 1-Year Follow-Up.

Vaginal pixelated low power and long pulses (LPLP) CO2 laser has been suggested as an optional treatment for stress urinary incontinence (SUI) with many studies reporting short-term improvements. The objective of this study was to assess the 1-year subjective and objective efficacy of vaginal CO2 laser in women with urodynamic SUI. This was a prospective multicenter study. Patients with confirmed urodynamic SUI graded as mild or moderate were included. We used three sessions of fractional pixelated CO2 laser for vaginal application and followed up the patients at 6 and 12 months. We used the following measures at follow-up: 1-hour pad test (ICS protocol), questionnaires including Pelvic Floor Distress Inventory 20 (PFDI-20), Pelvic Floor Impact Questionnaire (PFIQ), Patient Global Impression of Improvement (PGI-I), and a 3-day urinary diary. The urodynamic assessment was repeated at 6 months. Fifty-two patients with SUI had three laser treatments, of whom 48 completed a 6-month follow-up and 42 patients completed 12-month follow-up. No serious adverse events were recorded during the study period. A significant reduction on the 1-hour pad test was found from baseline (6.3 ± 1.6 g) to the 12-month follow-up (3.7 ± 1.4 g, P < 0.05) was found. PGI-I showed 75.0%, 61.9%, and 64.3% improvements at 3, 6, and 12 months, respectively. PFDI improved significantly and consistently from baseline until 12 months (37.2 ± 3.89 to 16.1 ± 3.7, P < 0.05). Similarly, PFIQ showed significant improvements from the first treatment up to 12 months. Urodynamic assessment at 6 months showed that 41.4% of patients had no stress incontinence. The vaginal CO2 laser was found to be effective for mild-to-moderate SUI over a follow-up period of 1 year, according to a variety of objective and subjective parameters. The wide range of parameters enables optimal patient consultation and subsequent treatment. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Laser-Induced Tar-Mediated Sintering of Metals and Refractory Carbides in Air.

Refractory metals and their carbides possess extraordinary chemical and temperature resilience and exceptional mechanical strength. Yet, they are notoriously difficult to employ in additive manufacturing, due to the high temperatures needed for processing. State of the art approaches to manufacture these materials generally require either a high-energy laser or electron beam as well as ventilation to protect the metal powder from combustion. Here, we present a versatile manufacturing process that utilizes tar as both a light absorber and antioxidant binder to sinter thin films of aluminum, copper, nickel, molybdenum, and tungsten powder using a low power (<2W) CO2 laser in air. Films of sintered Al/Cu/Ni metals have sheet resistances of ∼10-1 ohm/sq, while laser-sintered Mo/W-tar thin films form carbide phases. Several devices are demonstrated, including laser-sintered porous copper with a stable response to large strain (3.0) after 150 cycles, and a laserprocessed Mo/MoC(1-x) filament that reaches T ∼1000 °C in open air at 12 V. These results show that tar-mediated laser sintering represents a possible low energy, cost-effective route for engineering refractory materials and one that can easily be extended to additive manufacturing processes.

Study on microstructure and mechanical properties of Ni60 + WC/Ni35/AISI1040 functional surface gradient structure of remanufacturing chute plate for the mining scraper by a low cost high power CO2 laser cladding technique

CO2 laser cladding is a type of green remanufacturing technology, which is of many technical advantages in repairing and remanufacturing industry, especially for some large-scale key mining equipment or parts due to its characteristics of high quality, high efficiency and environmental protection (e.g. energy and material saving). In this paper, the chute plate of coal mining scraper is fixed and remanufactured by CO2 laser cladding technique. Ni60, WC, Ni35, IG55 and other composite powders are selected to design and build the gradient functional structure for chute plate in order to improve the reproduced lifetime. A lot of high power low cost CO2 laser cladding tests are carried out on the matrix material (AISI 1040 steel plate) of old attrite chute plate. The optical microscope, SEM, XRD, microhardness test and wear experiment are adopted to analyze the relationships among the laser cladding process, the overlaying composite material, gradient functional structure and mechanical properties of the remanufacturing scraper’s chute plate. The research results show that laser power and scanning speed are the dominant cladding process parameters, which have a significant influence on the geometric dimension (including width and height), dilution rate and hardness of the deposited layer. These composite powders (especially including the rare earth metals) are the key factor to form the gradient functional structure. The laser cladding Ni60 + WC/Ni35/AISI1040 composite gradient functional structure has a reasonable toughness and strength of the transition layer structure, and a high hardness and wear-resistant surface functional layer, so the fixed and remanufactured product has formed good ductile plasticity and wear resistance properties as a result of the gradient functional structure. The unique Ni60 + WC/Ni35/AISI1040 gradient functional structure makes sure that the chute plate of mining scraper has excellent comprehensive performance, which is satisfied with the service requirements of mechanical parts or equipment in the harsh working environment of the mining industry. This research work provides technological guidance for the fix and remanufacturing chute plate, and achieves the goal of low cost, high efficiency and long life reproduced chute plate of mining scraper.

Estudio experimental sobre el corte con láser de CO2 a baja potencia del compuesto de plástico reforzado con fibras naturales

La aplicación de los plásticos reforzados con fibras naturales en la industria puede aumentar mediante el uso de tecnologías más rápidas y flexibles, como el corte por láser. La naturaleza anisotrópica y el grado de combustión de las fibras naturales en este tipo de compuestos hacen que el procesamiento con láser sea muy desafiante. Este estudio trata sobre el rendimiento de corte de un láser de CO2 a baja potencia, para cortar placas de compuestos poliméricos (matriz de resina poliéster y epoxi), reforzado con fibras naturales (abacá y cascarilla de arroz), de 3 mm de espesor promedio. Se empleó un diseño experimental DOE y un análisis de varianza Anova para determinar los parámetros significativos e influyentes en la calidad de corte y el efecto térmico en el material. Los parámetros de procesamiento fueron la potencia de corte, velocidad de corte y tipo de matriz termoestable. Los cortes con una zona mínima afectada por el calor, de aproximadamente 600 mm y un Ra mínimo de 3.18 μm, se lograron al trabajar con 76 W y 14 mm/s de potencia y velocidad de corte, respectivamente, en el material compuesto de matriz poliéster reforzado con fibra de arroz.

Post-Processing of FDM 3D-Printed Polylactic Acid Parts by Laser Beam Cutting.

In this paper, the post-processing of 3D-printed poly lactic acid (PLA) parts is investigated. Workpieces are manufactured by fused deposition modeling (FDM) 3D printing, while they may have defects in some areas such as edges. A post-processing is introduced here for 3D-printed samples by low power CO2 laser. The thickness of the FDM samples are 3.2 mm and printed by optimum conditions. Effects of process parameters such as focal plane position (−3.2–3.2 mm), laser power (20–40 W), and laser cutting speed (1–13 mm/s) are examined based on the design of experiments (DOE). Geometrical features of the kerf; top and bottom kerf; taper; ratio of top to the bottom kerf are considered as output responses. An analysis of the experimental results by statistical software is conducted to survey the effects of process parameters and to obtain regression equations. By optimizing of the laser cutting process; an appropriate kerf quality is obtained and also optimum input parameters are suggested. Experimental verification tests show a good agreement between empirical results and statistical predictions. The best optimum sample with 1.19 mm/s cutting speed, 36.49 W power and 0.53 mm focal plane position shows excellent physical features after the laser cutting process when 276.9 μm top and 261.5 μm bottom kerf width is cut by laser.

Low-power CO2 laser-fabricated catalyst for the remediation of Reactive Red-45: Intense product analysis using LC-MS and HPIC

In this study, we report a simple method to synthesize a novel green nanocatalyst using titanium dioxide, graphene and Citrus sinensis peel extract using a low-power CO2 laser fabrication. The relevance of the resulting nanomaterial (Lp-TiO2/G-nCSP) for the photocatalytic degradation of Reactive Red-45 (RR-45) was studied exhaustively. Compared to the commercial TiO2 photocatalyst, the green synthesized and laser-fabricated nanocatalyst exhibited better UV-light irradiated photocatalytic activity for RR-45 degradation. The laser fabricated nanocatalyst was systematically characterized by scanning electron microscope (SEM), Fourier transform infrared spectrum (FTIR) and X-ray diffraction (XRD). At optimum conditions, the dye was completely degraded in 10 min by Lp-TiO2/G-nCSP nanocatalyst. LC-MS and HPIC profiles of RR-45 after the photodegradation proved the efficacy of the adopted strategy, and novelty of the synthesized nanocatalyst towards the RR-45 degradation.

Effect of CO2 Laser and 1.23% Acidulated Phosphate Fluoride on Acid Resistance and Fluoride Uptake of Human Tooth Enamel: An In Vitro Assessment

To evaluate the effectiveness of CO2 laser treatment before applying 1.23% acidulated phosphate fluoride (APF), through topically applied 1.23% APF solution, and after applying 1.23% APF on acid resistance and fluoride uptake of the enamel. Sixty non-carious human premolars were extracted due to the orthodontic reason and stored in distilled water solution under refrigeration. Using a water-cooled diamond disc, enamel slabs of 4 mm × 4 mm × 1.5 mm were cut from the buccal surface of each tooth. Sixty samples were randomly divided into one control group and five test groups of 10 premolars each. Solution was prepared for wet chemical analysis followed by fluoride analysis that was carried out using a fluoride ion selective electrode (Thermo Scientific Orion 4-Star Plus ISE Meter). The weight of enamel (WE) was determined from the amount of calcium (Ca) etched away considering the fact that the Ca content of the human enamel is 37.4 wt%. The subgroups were statistically analyzed using ANOVA for fluoride determination and evaluation of acid resistance. There was a significant increase in acid resistance of enamel slabs when treated individually or in combination of a low-power CO2 laser and 1.23% APF solution. Application of 1.23% APF solution after low-power CO2 laser treatment showed maximum increase in acid resistance. Application of a low-power pulsed CO2 laser through topically applied 1.23% APF solution resulted in a detrimental effect of the human tooth enamel with resultant decrease in acid resistance. High fluoride uptake does not necessarily indicate increased acid resistance. The present study provides evidence that a low-power CO2 laser can be used effectively in combination with topically applied 1.23% APF solution in order to make the enamel more resistant to acid attack, thereby helping in controlling dental caries.

Assessment of Inhibition of Mineral Loss from Human Tooth Enamel by Carbon Dioxide Laser and 1.23% Acidulated Phosphate Fluoride.

Aims and Objectives:The efficacy of carbon dioxide (CO2) laser irradiation combined with fluoride in inhibiting enamel demineralization has been demonstrated by several laboratory investigations. However, there are very few reports about the in situ or in vivo caries preventive effect of CO2 laser combined with topical fluoride on dental enamel. Hence, an in situ study was designed and carried out to assess inhibition of mineral loss from human tooth enamel by CO2 laser and 1.23% acidulated phosphate fluoride (APF).Material and Methods:Impressions of upper and lower arch of the volunteers were made in alginate impression material. Study models were poured, duplicated, and duly labeled. On the working model, appliances were fabricated in acrylic resin to fit the upper dental arch of the volunteers. Four enamel slabs (one from each group) were fitted on the palatal surface of the appliance as close as possible to posterior teeth. Surfaces of slabs were kept below the outer surface of acrylic. The analysis was done using SPSS version 15 (SPSS Inc., Chicago, IL, USA) Windows software program.Results:Statistically significant increase in inhibition of mineral loss of enamel slabs when treated individually or in a combination of low power CO2 laser and 1.23% APF solution. The application of 1.23% APF solution after low power CO2 laser treatment showed maximum inhibition of mineral loss.Conclusion:The combined use of this specific laser treatment plus fluoride was more successful than either laser treatment or fluoride alone in the inhibition of mineral loss in the mouth. The results of this study also suggest that the combination of low power laser treatment with fluoride therapy may be effective as a caries inhibition treatment.

Study of the metallurgical bond between 316 steel substrates and NiCrAlY coating sprayed by HVOF and irradiated with a low power CO2 laser

ABSTRACT Coatings are used to promote the thermal protection of metal alloys. In the aeronautical industry, the coatings used to protect the turbine blades are called Thermal Barrier Coatings (TBC). The use of NiCrAlY is an alternative as a bonding layer in coatings for turbine blades and it is possible to increase its useful life. This work aims to study the metallurgical bond between the 316-stainless steel substrate and the NiCrAlY coating which was sprayed through the High-Velocity Oxygen-Fuel (HVOF) and after irradiated by a CO2 laser beam with power of 125 W and speed of 50 mm/s. The samples were characterized by scanning electron microscopy (SEM) and the semi-quantitative analysis energy dispersive spectroscopic (EDX) showed that the chemical composition of the coating and the substrate have maintained its original stoichiometry. The line scan analysis is a technique of the EDX to analyze the diffusion between the main chemical elements of 316 steel and NiCrAlY and X-ray diffraction by identifying the alumina AL2O3 phases on the sample surface and the results showed the metallurgical bond between substrate and coating.

Assessment of combined fractional CO2 and tranexamic acid in melasma treatment

Melasma continues to be a disease that is difficult to treat with no fully satisfactory results. The role of a fractional CO2 laser in its treatment is controversial. The addition of tranexamic acid (TXA) might be helpful. To assess the efficacy of a low-power fractional CO2 laser alone versus its combination with tranexamic acid used either topically or intradermally for melasma treatment. A randomized comparative split-face study included a total of thirty female patients with bilateral, symmetrical melasma. The whole face was subjected to treatment via a low-power (12 Watts) fractional ablative CO2 laser. One side was randomly assigned to topical application of tranexamic acid solution after the session immediately or intradermal microinjection of tranexamic acid prior to the laser session. Sessions were conducted every 4-6 weeks for five consecutive sessions. Assessments were done using the melasma area severity index MASI score, melanin index (MI), and erythema index (EI) before sessions and 2 weeks after the final session. After treatment, there was significant reduction in the MASI score on both sides of the face; the side treated with the fractional CO2 laser alone and the side treated with fractional CO2 laser combined with TXA (topically or intradermal injection) (P-values 0.007, <0.001, and 0.016, respectively). MI was significantly lower on the side receiving fractional CO2 laser alone and the side receiving fractional CO2 laser combined with intradermal injection of TXA (P-values <0.001 and 0.003, respectively), while the EI showed significant improvement only on the side receiving fractional CO2 laser alone (P-value = 0.023). Although patients reported no differences in improvement on either treated side, the degree of improvement regarding the MASI score was better on the side receiving fractional CO2 laser alone. Regarding MI, the degree of improvement was higher on the side receiving fractional CO2 laser combined with intradermal injection of TXA than on the side receiving fractional CO2 laser alone; however, this improvement did not reach statistical significance. Minimal complications occurred in the form of mild pain. A low-power fractional CO2 laser is an effective, safe treatment for melasma. However, the addition of tranexamic acid (either topically or intradermally) to a fractional CO2 laser should be further studied. Lasers Surg. Med. 51:27-33, 2019. © 2018 Wiley Periodicals, Inc.

“Industrial applications of lasers” at the University of Vigo as legacy of Professor Mariano Pérez-Amor

From the early days in a modest laboratory equipped with a low power CO2 laser, more than thirty years have gone under the direction of Prof. Mariano Pérez-Amor first and Prof. Juan Pou Saracho later, transforming the initial status of the young research group to the current one under a watchword: supportive team work. During these years we have diversified our research areas, including processes at the nano-scale, processing and synthesizing materials of diverse nature, as well as introducing and patenting new laser-assisted processes and opening horizons to some laser applications well-established in the industry. All of it, with the commitment of our founder, the team that he has formed, in constant renewal, and the collaborating researchers in other national and international centers supported with public and private funding from different regional, national and European organizations.This paper is a modest tribute to Prof. Mariano Pérez-Amor who passed away on January 14th 2018.

Fast photocatalytic degradation of dyes using low-power laser-fabricated Cu2O-Cu nanocomposites.

In this study, we report a simple method to controllably synthesize Cu2O–Cu nanocomposites by using a low-power CO2 laser, and application of these nanomaterials for photocatalytic degradation of methylene blue (MB). Our experiments demonstrate that efficient tailoring of the Cu2O–Cu nanocomposites can be realized by accurate control and optimization of the ambient parameters, such as laser energy and NaOH concentration. Compared to hydrothermally fabricated Cu2O–Cu catalysts, the laser-reduced composites exhibit better visible-light photocatalytic activity for MB degradation, which could be attributed to the formation of special catalytically active structures on the nanocomposite surface. Under the conditions of 10 mA laser irradiation and 5 M NaOH addition, the fabricated Cu2O–Cu composites had the highest catalytic activity. The degradation rate of MB is 90.10% after visible-light irradiation for 50 min under the optimum conditions. The as-synthesized Cu2O–Cu composites showed selective dye degradation, and exhibit relatively higher photocatalytic efficiency for positively charged dyes. This work could lead to facile synthesis of high-performance photocatalysts for fast removal of environmentally hazardous dyes from aqueous solution.