Diffuse Reflectance Research Articles

Laser Control of Specular and Diffuse Reflectance of Thin Aluminum Film-Isolator-Metal Structures for Anti-Counterfeiting and Plasmonic Color Applications

Plasmonic structural color originates from the scattering and absorption of visible light by metallic nanostructures. Stacks consisting of thin, disordered semicontinuous metal films are attractive plasmonic color media, as they can be mass-produced using industry-proven physical vapor deposition techniques. These films are comprised of random nano-island structures of various sizes and shapes resonating at different wavelengths. When irradiated with short-pulse lasers, the nanostructures are locally restructured, and their optical response is altered in a spectrally selective manner. Therefore, various colors are obtained. We demonstrate the generation of structural plasmonic colors through femtosecond laser modification of a thin aluminum film–isolator–metal mirror (TAFIM) structure. Laser-induced structuring of TAFIM’s top aluminum film significantly alters the sample’s specular and diffuse reflectance depending on the fluence value and the number of times a region is scanned. A “negative image” effect is possible, where a dark field observation mode image is a negative of a bright field mode image. This effect is visible using an optical microscope, the naked eye, and a digital camera. The use of self-passivating aluminum results in a long-lasting, non-fading coloration effect. The reported technique could be used in anti-counterfeiting and security applications, as well as in plasmonic color printing and macroscopic and microscopic marking for personalized fine arts and aesthetic products such as jewelry.

A Review of the Application of the Laser-Light Backscattering Imaging Technique to Agricultural Products

Growing concerns about food safety and waste have increased consumer demand for high-quality agricultural products, particularly at the postharvest stage. This demand has prompted the development of non-destructive methods to assess or inspect the internal quality of fruits and vegetables. The backscattering imaging technique, also known as diffuse reflectance imaging, is considered a highly promising approach. Numerous studies have focused on practical applications, using laser light at selected wavelengths to develop quick multispectral methods. Due to the rapid interaction of photons with biological tissue, together with the highly computational performance of machine vision, backscattering imaging can offer a valuable alternative to traditional methods. Its primary benefits include quick measurements without chemical sample preparation, easy integration with high-throughput automatic quality control, and reduced waste, since this non-destructive technique does not damage samples. This review presents a comprehensive overview of backscattering imaging, including the measurement geometry, data analysis, and design considerations for vision systems. Additionally, it explores this technique’s advantages, challenges, and accuracy, as demonstrated using various case studies.

Chemical synthesis of NiO nanoparticles from Solanum trilobatum leaf extract for antibacterial and cytotoxic properties

The chemical precipitation approach was employed to synthesize Nickel oxide nanoparticles (NiONPs) using Solanum trilobatum leaf extract as the stimulant and Nickel nitrate as the precursor. The Nickel oxide is examined using a range of characterization methods including X-ray diffraction, Fourier Transform Infrared spectroscopy, High-Resolution Transmission Electron Microscopy, High-Resolution Scanning Electron Microscopy, X-ray photoelectron spectroscopy, Thermo gravimetric Analysis/Derivative Thermo gravimetric Analysis, Diffuse Reflectance Spectroscopy, cytotoxicity and antimicrobial investigations The X-ray diffraction examination determined that the average size of the crystals increases as the quantities of leaf extract in the NiO2 composites rise. The decrease in line broadening (β) value and the increase in leaf extract concentrations may be the cause of this phenomenon. The FTIR spectrum confirms that the as-synthesized NiO-NPs are of great purity and match well with the XRD pattern. The thermal stability of the synthesized samples was determined using TGA/DTG analysis. The analysis was conducted in an air atmosphere, with the temperature increasing at a rate of 10°C per minute. The temperature range for the analysis was from room temperature to 750°C. The optical properties are determined by the use of Diffuse Reflectance Spectroscopy, which examines the coordinated movement of electrons in the conduction band when exposed to electromagnetic waves. Rat skeletal muscle cell line and SKMEL cancer cells were cultured on 96-well plates and incubated at 37°C and 5 % CO2 for 24 hours to allow them to adapt to the culture conditions. An investigation was conducted to assess the antibacterial properties of synthesized nanocomposites against two types of bacteria: gram-positive Staphylococcus aureus (MTCC No: 87) and gram-negative Escherichia coli (MTCC No: 443), in order to explore their potential for biological applications.

Oxidation of Toluene over the Pt-Embedded Mesoporous CeO2 Hollow Nanospheres with Advanced Catalytic Performances.

In this study, the novel Pt-embedded mesoporous CeO2 hollow nanospheres (Pt-MS-CeO2-H) with varying Pt contents (0.5-3.0 wt %) were facilely prepared. The Pt nanoparticles were one-pot embedded within the mesoporous shell of Pt-MS-CeO2-H and assisted with the reduction Ostwald ripening process. The traditional preparation methods often face challenges, such as the uneven distribution or aggregation of nanoparticles, as well as difficulty in maintaining high catalytic activity at low Pt content. Compared with the traditional supported Pt/MS-CeO2 catalyst, the embedding strategy facilitated precise control over the position, distribution, and uniformity of Pt nanoparticles within the CeO2 mesoporous shell. Additionally, the encapsulation process of Pt nanoparticles played a pivotal role in generating oxygen vacancies and activating surface chemical adsorption of oxygen. Resultantly, the toluene oxidation performances of 1Pt-MS-CeO2-H catalyst showed much lower T90 (171 °C) than 1Pt/MS-CeO2 (311 °C). To elucidate the underlying reasons, in situ diffuse reflectance infrared Fourier transform spectroscopy of toluene oxidation was employed to identify the reaction intermediates and pathways over these catalysts. In summary, the Pt-embedded mesoporous CeO2 hollow nanosphere catalysts were considered as potential candidates when designing high-performance toluene catalytic oxidation catalysts.

Breaking Barriers in Chalcogenide Perovskite Synthesis: A Generalized Framework for Fabrication of BaMS3 (M═Ti, Zr, Hf) Materials

AbstractChalcogenide perovskites have garnered increasing attention as stable, non‐toxic alternatives to lead halide perovskites. However, their conventional synthesis at high temperatures (>1000 °C) has hindered widespread adoption. Recent studies have developed low‐to‐moderate temperature synthesis methods (<600 °C) using reactive precursors, yet a comprehensive understanding of the pivotal factors affecting reproducibility and repeatability remains elusive. This study delineates the critical factors in the low‐temperature synthesis of BaMS3 (M═Zr, Hf, Ti) compounds and presents a generalized framework. Innovative approaches are developed for synthesizing BaMS3 compounds using this framework involving organometallics for solution deposition. The molecular precursor routes, employing metal acetylacetonates to generate soluble metal–sulfur bonded complexes and metal–organic compounds to produce soluble metal‐thiolate, metal‐isothiocyanate, and metal‐trithiocarbonate species, are demonstrated to yield carbon‐free BaMS3. These methods have achieved the most contiguous films of BaZrS3 and BaHfS3 using solution deposition to date. Furthermore, a hybrid solution processing method involving stacking sputter‐deposited Zr and solution‐deposited BaS layers is employed to synthesize a contiguous, oxygen‐free BaZrS3 film. The diffuse reflectance measurements indicate a direct bandgap of ≈ 1.85 eV for the BaZrS3 films and ≈ 2.1 eV for the BaHfS3 film under investigation.

Solar driven highly efficient photocatalyst based on Dy2O3 nanorods deposited on reduced graphene oxide nanocomposite for methylene blue dye degradation.

In recent years, the demand for rare earth elements has surged due to their unique characteristics and diverse applications. This investigation focuses on utilizing the rare earth element dysprosium oxide (Dy2O3) for the photocatalytic oxidation of model pollutants under solar light irradiation. A novel RGO-Dy2O3 nanocomposite photocatalyst was developed using a solvothermal approach, Dy2O3 nanorods uniformly deposited onto reduced graphene oxide (RGO) nanosheets. Comprehensive characterization techniques, including Brunner-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), Raman spectroscopy, high resolution - transmittance electron microscopy (HR-TEM), field emission-electron scanning microscopy (FE-SEM), atomic force microscopy (AFM), electron paramagnetic resonance spectroscopy (EPR), photoluminescence spectroscopy (PL), and electrochemical impedance spectroscopy EIS techniques. The UV-visible diffusive reflectance spectroscopy (UV-Vis-DRS) studies revealed a band gap energy of 3.18eV and a specific surface area of 114 m2/g for the fabricated RGO-Dy2O3 nanocomposite. The RGO-Dy2O3 nanocomposite demonstrated a high photocatalytic degradation efficiency of 98.1% at neutral pH for methylene blue (MB) dye for the dye concentration of 10ppm. The remarkable photocatalytic performance was achieved within 60min under solar light irradiation. Reusability tests demonstrated stability, maintaining over 90% photocatalytic efficiency after three cycles. The EPR spectra and quenching experiments confirmed that photogenerated hydroxyl radicals significantly influence the photodegradation processes. The RGO-Dy2O3 nanocomposite photocatalyst, with its green, easy preparation process and recycling capabilities, presents an ideal choice for various applications. It offers a viable alternative for the photocatalytic degradation of organic dyes in real wastewater, contributing to sustainable environmental remediation.

Synthesis, Crystal Structure, and Optical Properties of a New Quaternary Tin Polychalcogenide K2BaSnSe5

AbstractOne new quaternary tin polychalcogenide K2BaSnSe5 has been synthesized by high temperature solid‐state reaction. It crystallizes in the centrosymmetric space group P21/c of the monoclinic system with cell constants a=11.948(2) Å, b=10.367(2) Å, c=9.2902(19) Å, β=91.33(3)°, and V=1150.4(4) Å3. The compound features an interesting zero‐dimensional structure consisting of SnSe5 units, made up of SnSe4 tetrahedra and [Se2] unit, with K+, Ba2+ cations locating in the interstitial sites for charge‐balance. Diffuse reflectance spectrum indicates semiconducting property with an optical band gap of 1.45 eV. Theoretical calculations demonstrate that the band gap of the title compound is determined by [SnSe5] units, and the title compound has a large birefringence of 0.28 at wavelength 1.06 μm, which implies that K2BaSnSe5 may be an intriguing photoelectronic material.

Aliovalent Doping of Niobium and Tantalum Pentoxide as Potential Alternative Support Material for Fuel Cell Catalysts

AbstractAs the usually used Carbon Blacks (CB) as support materials in fuel cell catalysts are thermodynamically unstable, alternative supports with high chemical stability and electrical conductivity are to be found. After the investigation of Nb and Ta‐doped SnO2 in an earlier publication, which revealed interesting conductivity properties, we expanded our portfolio of mutual doping of elements of stable oxides into the oxides of the others by reporting here on the Sn, Hf and W‐doping as guests into the base oxides Nb2O5 and Ta2O5. The changes in unit cell parameters as indicators for the doping success were investigated in the doping range of x=0–10 mol % guest fraction. From a complete solubility of the guest ions in case of Hf and W‐doping in the base oxides to a limited solubility in case of Sn‐doping, a whole spectrum of different results was obtained. Additional insight came from UV/vis spectroscopic investigations in diffuse reflectance as well as electrical conductivity measurements.

Ta4SBr11: A Cluster Mott Insulator with a Corrugated, Van der Waals Layered Structure.

The compound Ta4SBr11 was prepared by a comproportionation reaction of tantalum bromide with tantalum and elemental sulfur. The crystal structure, as refined by single-crystal X-ray diffraction, is composed of clusters with Ta4S cores, arranged in corrugated van der Waals layers. Individual layers appear to be displaced relative to each other along one direction. Successful crystal growth in a melt of CsBr yielded black platelets of Ta4SBr11, which were used to investigate the electrical properties of the compound. The electronic structure was studied by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and by density functional theory (DFT) band structure calculations, revealing this material to be a small-gap semiconductor. DFT results, in combination with magnetic susceptibility measurements, suggest that metallicity originating from the one unpaired Ta d electron per cluster is most likely suppressed by electronic correlations, forming a cluster Mott insulator.

Synthesis and characterization of zinc-doped hematite nanoparticles for photocatalytic applications and their electronic structure studies by density functional theory

Hematite nanoparticles doped with 1, 3 and 5 % Zn (all % are in molar) were prepared using mechanical alloying. Morphological and phase structure studies using scanning electron microscopy and X-ray diffraction showed nanoparticles possessing a semi-spherical shape and particle size of <50 nm crystallized in rhombohedral structure. The lattice parameters of hematite increased upon Zn doping. The energy-dispersive X-ray and Fourier-transform infrared results demonstrated that Zn was successfully incorporated. The optical behavior of nanoparticles was examined by UV–Vis diffuse reflectance spectroscopy and revealed that Zn doping increased the absorption intensity in the visible light region and decreased the band gap from 1.95 (hematite) to 1.83 eV (3 % Zn). Methylene blue dye degradation by the 3 % Zn sample proved doubling of the photocatalytic activity due to electronic structure modification upon Zn doping. First principles studies using density functional theory performed to investigate the effect of Zn on the electronic band structure of hematite showed that Zn doping caused band gap reduction, causing formation of new energy states, mainly above the valence band. Eventually, the enhancement of Urbach energy and reduction of effective mass, respectively accountable for increasing the relaxation time and mobility of charge carriers, were considered the two main mechanisms regarding the increased photocatalytic behavior of hematite by Zn doping.

Fabrication of CoTiO3/MgIn2S4 S–scheme heterojunctions with efficient charge separation to enhance the photocatalytic activities of hydrogen generation and formaldehyde removal

The efficient separation of photoinduced charge carriers is a primary factor in the catalytic performance of photocatalysts. Constructing S-scheme heterojunctions is a prospective strategy to efficiently and spatially separate photoinduced charges while retaining strong oxidation and reduction capacities of the catalyst system. Herein, CoTiO3/MgIn2S4 (abbreviated x% CTO/MIS, where x% represents the mass ratio of CTO-to-MIS; x = 5, 10, 15, 20, and 25) heterojunctions were successfully synthesized using a hydrothermal method. These heterojunctions exhibited highly efficient and reusable visible-light photocatalytic properties for hydrogen (H2) generation and formaldehyde (HCHO) degradation. Notably, the 15 % CTO/MIS demonstrated an admirable H2 evolution activity of 631.77 μmol·g−1·h−1, with AQE = 2.25 % at λ = 420 nm, and an HCHO degradation rate of 67.18 %. The intermediate products generated during HCHO removal were identified applying in situ diffuse reflectance infrared Fourier transform spectroscopy. The exceptional catalytic performance of the synthesized materials was attributed to the boosted light absorption and utilization, rapidly separation, and transfer of photoproduced charge carriers, which resulted from the internal electric field of the S-scheme mechanism. Moreover, the S-scheme electron transfer pathway for the CTO/MIS catalyst system during the photocatalytic process was confirmed using electron spin resonance spectroscopy, free-radical capturing tests, density functional theory calculations, in situ X-ray photoelectron spectroscopy, and semiconductor energy band theory. The study offers an innovative perspective for establishing S-scheme heterojunctions with highly efficient and stable photocatalytic activity for H2 generation and HCHO removal.

Compositing of rGO to TiO2 by Low-Temperature Treatment and Their Photocatalytic Properties

Reduced graphene oxide (rGO)/TiO2 nanocomposites were prepared by low-temperature and low-pressure heat treatment. The structure and photocatalysis performance of the composites were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and UV-visible diffuse reflectance spectrum (UV-Vis DRS). The photocatalytic degradation performance of methyl orange (MO) by composites with different raw material ratios was studied under simulated solar-irradiation conditions. Results indicated that graphene oxide (GO) was reduced to graphene during heat treatment and bonded well with TiO2. Compared with TiO2, GO addition greatly improved its photocatalytic efficiency. Under simulated sunlight irradiation, the samples exhibited good photocatalysis performance. Within 50[Formula: see text]min, MO can be rapidly degraded by TiO2/40% rGO composite.

A high-resolution acoustic goniometer for characterizing sound diffuser reflections

Noise control engineering and architectural acoustics practice have widely applied diffusing elements and devices to create surface scattering and diffuse reflections. An acoustical goniometer in the form of a circular microphone array has been used to characterize scattered responses for various types of diffusing elements/devices. This research is also intended for experimental validation of diffraction simulations of diffusing devices based on the physical theory of diffraction (PTD). To cope with experimental challenges, particularly for the research in the physical theory of diffraction, an acoustic goniometer must achieve a high enough angular resolution in addition to fulfilling far-field requirements. This paper discusses practical implementations and experimental results of portable goniometers with a radius of up to five meters and an angular resolution of 1.25 degrees. The practical implementation is intended to be easily deployable in empty, indoor spaces of sufficiently large dimensions for scattered reflection characterization. This paper discusses an effort of increasing experimental efficiency of characterization procedures for oblique incidences.

Experimental demonstration of a simple free-space loss model for diffuse reflections in guided-mode LiDAR

Experimental demonstration of a simple free-space loss model for diffuse reflections in guided-mode LiDAR

Mechanistic Study of the Electrochemical Reduction of CO2 in Aprotic Ionic Liquid in Air.

The capture and electrochemical conversion of dilute CO2 in air is a promising approach to mitigate global warming. Aiming to increase the efficiency of the electrochemical reduction of CO2, we fabricated electrodes and developed a custom-designed sealed electrochemical reaction system to study the mechanism of this conversion. The performance of three metal electrodes, Ag, Cu, and SUS 316L, was compared in an aprotic ionic liquid as the electrolyte to monitor the CO2 concentration and chemical reactions using a CO2 sensor and diffuse reflectance infrared Fourier transform spectroscopy and Raman spectroscopy in CO2/N2 (400 ppm CO2 and 99.96% N2) or synthetic air (400 ppm CO2, 21% O2, and 79% N2). The CO2 concentration decreased at negative potentials and was more drastic in synthetic air than in CO2/N2. At negative potential in synthetic air, IR revealed carbon monoxide, carbonate, or peroxydicarbonate on the Ag, Cu, or SUS 316L electrodes, respectively. Reaction intermediates were identified using Raman spectroscopy. Superoxide (O2•-), produced by the reduction of O2 on each electrode, promotes the electrochemical reduction of CO2 whose reduction potential is higher on the negative side than that of O2. This research deepens our understanding of the electrochemical capture/release and conversion of dilute CO2.

Design and optimization of acoustic reflector for uniform diffusion

Sound diffusion performance is considered as an important issue in building acoustics. A well-diffused sound field can effectively enhance the human listening experience. To this end, we have investigated several optimization strategies to design a sub-wavelength acoustic metasurface that can achieve broadband uniform diffuse reflections. These designs are based on Fresnel lens surface, groove-like structure, level-set method, topology optimization approach, respectively. Meanwhile, a strategy combining Monte-Carlo searches and other derivative-free algorithms has been analyzed and used to ensure, as far as possible, a global optimum for the objective function when dealing with the multi-peak problem encountered in complex sound fields. Numerical simulations show that the resulting metasurfaces with the best diffusion performance have similar configurations between different design methods. The simulated sound pressure field was also verified by experimental measurements. From a general perspective, the proposed optimization strategy and simulation framework can provide a greater degree of freedom for geometric configuration and benefit the design of interior components in building acoustics.

Catalytic and Electrochemical Study of Cu-ZSM-5/MCM-41.

Hierarchically structured micro-mesoporous ZSM-5/MCM-41 composite materials incorporating copper ions were synthesized using pre-synthesized ZSM-5 and cetyltrimethylammonium bromide (CTAB) as a template for forming the MCM-41 structure. The composites were characterized through powder X-ray diffraction, N2 adsorption-desorption, diffuse reflectance spectroscopy (UV-vis DRS), Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and energy dispersive X-ray spectroscopy. X-ray diffraction confirmed well-ordered ZSM-5 and MCM-41 structures, and UV-vis DRS showed successful copper ion incorporation. N2 adsorption-desorption revealed the presence of both microporous and mesoporous structures. To evaluate their catalytic performance, Cu-incorporated ZSM-5/MCM-41 composite catalysts were assessed through the oxidation reaction of ethylbenzene using tert-butyl hydroperoxide (TBHP) as the oxidizing agent. With a 9% (w/w) Cu-ZM-5 (5 wt % copper-incorporated ZSM-5/MCM-41) catalyst and an oxidant to ethylbenzene molar ratio of 2:1 at 40 °C in the absence of a solvent for 4 h, the process yielded acetophenone (93.2%) as the major product. Additionally, these Cu-incorporated composites were examined as electrode materials for electrochemical storage. Cyclic voltammetry and galvanostatic charge-discharge studies showed that Cu-ZM-5 exhibited pseudocapacitive behavior, with a capacitance of up to 366 F g-1 at a current density of 1 A g-1, surpassing ZSM-5 and ZSM-5/MCM-41. These results highlight Cu-ZM-5's potential as an effective electrode material for electrochemical storage applications like supercapacitors.

Integrating environmental remediation with biodiesel production from toxic non-edible oil seeds (Croton bonplandianus) using a sustainable phyto-nano catalyst

In the current situation of the environmental uprising toxicology, rising global temperature, and energy-depleting urges to explore and discover more renewable and greener ecological-benefiting energy resources. Biobased renewable fuels generated by using waste products can help in waste management, climate change mitigation, and a low-carbon future. The main objective of this research is to produce environment-friendly and cost-effective biofuel. The potentiality of the novel, toxic, waste, and inedible feedstock Croton bonplandianus was evaluated for biodiesel synthesis through transesterification utilizing a Phyto-nano catalyst of potassium oxide prepared by Croton bonplandianus floral stalk's aqueous extract focusing on waste management. Phyto-nano catalyst characterization was done through innovative tools such as Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Zeta Potential (ZP), X-Ray Diffraction (XRD), Fourier Transformed Infrared spectroscopy (FTIR), and Diffuse Reflectance Spectroscopy (DRS). The characterization results revealed that the potassium oxide phyto-nanocatalyst possesses an average nanoparticle size of 44.5 nm. This size is optimal for enhanced catalytic activity, indicating significant potential for efficient catalysis. The highest yield (94 %) of biodiesel was secured at optimized reaction conditions of catalyst quantity (0.50 wt%), reaction time (180 min), methanol: oil ratio (9:1), and reaction thermal point (70 °C). Transformation of triglycerides to methyl esters was confirmed by GC/MS, NMR, and FTIR techniques. A total of 21 methyl esters were observed in Croton bonplandianus biodiesel confirmed via GC/MS results. Evaluation of fuel properties was done and matched with international fuel standards. The conclusive remarks for the conducted research are that Croton bonplandianus has a high potential for biodiesel production by applying Phyto-nanocatalysts of potassium oxide while dealing with hazardous environmental conditions and waste management. Phyto nanocatalyst of potassium oxide can be reused and gives the same yield after several cycles of reusability, this reusability of heterogenous Phyto nanocatalyst can reduce to total cost of biodiesel production and can contribute towards circular economy.

Diffuse reflectance spectroscopy and RGB-imaging: a comparative study of non-invasive haemoglobin assessment

Non-invasive assessment of haemoglobin (Hb) level in blood is a hot spot in the point-of-care biomedical diagnostics. Several optical methods are suggested as a solution, some of them being approved for clinical use. Still, there is no consensus on the accuracy of optical techniques, the quality of Hb assessment on different tissue sites, and on the ability of combined use of several optical techniques to improve the quality of Hb level prediction. In this work we examined the capabilities of two optical techniques—diffuse reflectance spectroscopy and RGB-imaging of the skin and fingernails areas—in detecting low blood Hb level. The test sample consisted of 240 adult volunteers with 70 volunteers exhibiting Hb level lower than 120 g/L. We show that using simple descriptors of the diffuse reflectance spectrum of the forearm skin and fingernails is applicable for predicting low blood Hb concentration (ROC-AUC = 0.84 ± 0.08), while RGB-imaging shows similar performance when applied to the fingernail areas (ROC-AUC = 0.83 ± 0.07), which can be considered perspective for clinical use and screening properties. We also report that while the joint use of predictions from two optical methods slightly improves the accuracy of non-invasive Hb level assessment (ROC-AUC = 0.86 ± 0.07), the effect is not as high as one might expect from combining predictions of truly independent modalities, indicating the limit of the accuracy one can expect with multimodal optical approach. We review this case and propose possible solutions towards more sensitive non-invasive optical determination of hemoglobin.

Fast and simultaneous prediction of inner quality parameters on intact mangos by near infrared spectroscopy: Impact of spectra pre-processing on prediction accuracy

Near infrared spectroscopy or known as NIRS has been widely employed in many fields including agriculture, especially for sorting and grading of agricultural products. Spectra pre-processing is one of the main factors affecting model accuracy and prediction capabilities of NIRS. The objective of the present study was to study the impact of different spectra corrections namely mean centering (MC), mean normalization (MN), de-trending (DT), multiplicative scatter correction (MSC), standard normal variate (SNV) and orthogonal signal correction (OSC), to the prediction accuracy of quality parameters: titratable acidity (TA) and soluble solids content (SSC) in intact mango. A total of 91 mango samples (cv. Kent) were used as dataset for calibration and external prediction which was separated by means of systematic sampling based on a property (SSBP) approach. Diffuse reflectance spectra (log1/R) were acquired and recorded in wavelength range of 1000 – 2500 nm by Antaris Fourier transform NIR instrument. Judging from calibration and prediction performance, MSC found to be the best spectra pre-processing method prior to prediction model development with R2 prediction are 0.72 for TA and 0.76 for SSC. Although MSC increase the prediction performances based on R2, RMSE, RPD and RER metrics compared to the baseline, the achieved RPD, 1.9 for TA and 1.8 for SSC of this findings are still poor and need improvements to achieve even higher levels of accuracy and reliability necessitates for real-time applications.