XPS Measurements Research Articles

Effect of oxygen vacancies on enhancing the photo-catalytic activity, photo-luminescence and electronic structure properties of nanostructured Y-doped CeO2

The exceptional characteristics of CeO2 and Ce1-xYxO2 (x = 0.03, 0.05 and 0.07) nanoparticles were reported in the manuscript supporting that Y3+replaces Ce3+/Ce4+leads to oxygen vacancies formation. The results of XRD measurements revealed FCC structure of decreased crystallite size of CeO2 with improved crystallinity. To investigate the surface morphology, HRTEM and SAED patterns were performed. EDX analyses were undertaken to discuss the elemental and compositional characteristics. The absorption spectra using UV–Vis–NIR spectroscopy were analyzed and red shifted absorbance was found to enhance with decreasing band gap values for increased Y doping. The Photoluminescence spectra depicted various emissions representing the development of various defects and oxygen vacancy with incorporation of Y content in the lattice with CCT values below 4000 K to be classified as warm yellow light for indoor applications. The development of oxygen vacancies in the CeO2 lattice was further supported by XPS measurements for core levels Ce 3d, O 1s and Y 3d. Furthermore, the XPS measurements also reported the valence states of elements, Ce with 3+ and 4+, Y with 3+ and O with 2- along with charged oxygen vacancies. The photo-catalytic analysis revealed that Y-doped CeO2 nanoparticles show better degradation using a variety of characterization. A degradation mechanism that illustrates the impact of oxygen vacancies created by Y-doping on the photo-degradation process has been proposed. The novelty of Y-doped CeO2 nanoparticles stems from their improved photo-catalytic activities, which are linked to structural changes and the formation of oxygen vacancies. This doping considerably affects the electrical structure, resulting in better light absorption and less electron-hole recombination. The detailed outcomes of present study suggested the use of Y-doped CeO2 nanoparticles in optoelectronics, spintronics devices and photo-catalyst applications.

Temperature dependent radiative and non-radiative recombination lifetimes of luminescent amorphous silicon oxynitride systems

In our previous work, we deeply researched the absolute photoluminescence (PL) quantum yields of luminescent modulating a-SiNxOy films with various N/Si atom ratios under different measurement temperatures. In this work, we further systematically studied the temperature dependent kinetic processes of radiative and non-radiative recombinations in a-SiNxOy systems in the visible light range. First, we investigated the structure of a-SiNxOy films and obtained the concentrations of both trivalent Si and N-Si-O defects related dangling bonds through XPS, FTIR and EPR measurements. Then we further tested the transient fluorescence attenuation of a-SiNxOy films detected at different emission wavelengths. We found that the PL lifetimes of a-SiNxOy films vary with the change of N-Si-O defect state concentrations, which is different from the typical PL decay characteristics of band tail related a-SiNx films previously reported. By combining the resulting PL IQE values with the ns-PL lifetimes, we further intensively redetermined the radiative and non-radiative recombination lifetimes of a-SiNxOy systems. The related radiative recombination rates were obtained (kr∼108 s−1), which can be compared to the results in the direct band gap.

Preparation and Characterization of Au Quantum Dots Using Laser in Benzene and Study of the Pulse Energy effect on Quantum Size

Here, findings from a study on pulsed laser ablating of noble Au targets submerged in benzene solvent and a study on the effect of pulse energy on quantum size are presented. Three samples of gold quantum dots (AuQDs) are synthesized at pulse fluence of 4, 8, and 12 J/cm2, which is referred to as F1, F2, and F3, respectively. The prepared AuQDs were characterized by UV-Vis, HR-TEM, XRD, XPS, EDX, FTIR, Raman spectroscopy and Photoluminescence measurement. AuQDs that were synthesized have monocrystalline and cubic (FCC) structure, according to XRD patterns. It was found that the direct optical energy gap of AuQDs is enhanced to 2.6 eV. The emission peak of AuQDs photoluminescence emission spectra is at roughly 481, 445, and 437 nm, for F1, F2, F3 samples, respectively. The quantum size was reduced to 2 nm for sample F3. This strategy has the ability to prepare pure AuQDs in one step, with promising biosensor and bioimaging applications.

Analysis of time-dependent hydrophobic recovery on plasma-treated superhydrophobic polypropylene using XPS and wettability measurements

In specific applications like ice-repellent coatings or membrane separation technology, wettability is a key parameter affecting the applicability of commodity polymers. This study presents a technique to fine-control the wetting properties of a hierarchically structured polypropylene surface, enabling the transition between superhydrophobic and superhydrophilic states. To demonstrate the tunability of the wetting properties of polypropylene (PP) substrate, we prepared in a consecutive way superhydrophobic (advancing contact angle (CAadv) of 152°) and superhydrophilic (CAadv of 0°) material by solvent-treatment and mild air plasma treatment. The optimal plasma treatment parameters to achieve superhydrophilic wetting behaviour, which is stable for at least one week of storage in air was also explored. Water contact angle measurement and X-ray photoelectron spectroscopy were used to monitor the time dependency of hydrophobic recovery on a hierarchically structured PP surface. With a simple model considering structural and wetting parameters, we characterized the droplet spreading behaviour of plasma-treated roughened surfaces, which exhibited superhydrophilic wetting behaviour with equilibrium CAadv of nearly 0°. The proposed model, which aligns well with experimental data, can be used to compare the droplet spreading behaviour of plasma-treated roughened surfaces.

Sulfuration-induced enhancement of photodetection performance of photoconductive detector based on Bi2O2Se thin film

Significant interlayer transmission obstacles and numerous interface barriers in two-dimensional material thin films impede charge transfer, degrading device performance. However, appropriate impurity ions can enhance charge mobility by creating transfer channels and regulating interface defect states. Herein, a series of Bi2O2SxSe1-x films were prepared by a one-step hydrothermal sulfurization method. The XRD and XPS measurement and analysis can confirm that the Se atoms have been replaced by the S atoms. The introduction of S atoms can effectively enhance the number of defects in Bi2O2Se, resulting in an increase in carrier concentration, thereby improving the conductivity of Bi2O2Se film. The photoconductive detectors fabricated from these Bi2O2SxSe1-x films showed improved detection performance compared to those made from the pristine Bi2O2Se film, and the responsivity is increased by nearly 1000 times. Notably, the detector based on Bi2O2S0.37Se0.63 film has high responsivity (47.7 mA/W) and fast response time (15 ms/25 ms). The simple thin film preparation method and good device performance make it have great potential for large-scale preparation.

Green synthesis and antimicrobial study on the catechin-functionalized Fe3O4-Ag magnetic nanocomposites

In this study, catechin-functionalized Fe3O4-Ag nanocomposites were synthesized by a hydrothermal method. The motivation for this study was to develop a novel antibacterial agent with enhanced stability and biocompatibility. The objective was to create a nanocomposite combining the antimicrobial properties of silver with the antioxidant and bioactive characteristics of catechin. We hypothesized that the synergistic effect of catechin and Fe3O4-Ag would yield a highly effective antibacterial material against common pathogens. The obtained nanocomposites were characterized by TEM, SEM, AFM, XPS, XRD, FTIR and physical property measurement system (PPMS). TEM images indicated that catechin-functionalized Fe3O4-Ag nanocomposites have a spherical morphology with an average size of 25.7 nm. The SEM and AFM imaging revealed that the nanocomposites appear as a number of large particles with average diameter of 581 nm. XPS and XRD and FTIR measurement confirmed the presence of catechin components, Fe3O4 and Ag in the nanocomposites. Taken together, we conclude that the catechin-Fe3O4-Ag nanocomposites in this study have a jujube cake structure in which the Fe3O4-Ag alloy nanoparticles serve as the jujube and the condensed catechin form into the cake substrate. The antimicrobial test indicated the catechin-functionalized Fe3O4-Ag nanocomposites have obvious inhibitory effects on E.coli, S.aureus, and C.albicans.

Fundamentals of copper(II) adsorption on phyllosilicate minerals relevant to crud formation in solvent extraction from heap leach liquors

Because of the common presence of different silicate minerals, like kaolinite, montmorillonite and muscovite as gangue minerals in the beneficiation of copper oxide ores, the interaction between copper(II) ions in solution and each of these minerals is a field of strong interest, considering their implications on the aggregation of these minerals in the extreme pH conditions typical of hydrometallurgical unit operations for copper production. After copper adsorption isotherms determination at pH 2 and 4, specific adsorption data were fitted to both Langmuir and Freundlich models. It was found that adsorption is systematically larger at pH 4, and that montmorillonite is the mineral that displays a larger adsorption capacity, as in principle expected by its larger cation exchange capacity, CEC. A good fitting to the Langmuir model was obtained for the three samples, and montmorillonite also appears to conform to Freundlich isotherm predictions, as the tested concentrations of copper(II) do not allow to reach saturation. Furthermore, some desorption is measured for kaolinite and muscovite at the highest copper concentrations, probably because of significant interactions between the adsorbed ions. No such desorption was detected in montmorillonite samples. An XPS analysis of the surfaces of the three minerals suggests that copper adsorption in kaolinite is not associated to a cation exchange process but rather to electrostatic interactions between silica-like faces of the clay. In contrast, ionic exchange of structural calcium (for montmorillonite) or potassium (in the case of muscovite) seems to be the predominant mechanism of Cu(II) adsorption in the other two samples. Electrophoretic mobility determinations agree with this hypothesis: the mobility (always negative, with no traces of charge inversion) decreases in absolute value when kaolinite particles are in contact with solutions of increasing copper concentration at pH 2 or pH 4. On the other hand, the electrophoretic mobility values of muscovite and montmorillonite showed a weak pH and copper concentration dependence, a result that matches well with the ion exchange processes detected in the XPS measurements.

Preparation of Ni-Cu-C composite catalysts prepared from mixed nickel and copper hydroxides for selective hydrogenation of 4-nitrophenol

A high-performance Ni-Cu-C composite catalyst was prepared from mixed nickel hydroxide and copper hydroxide, which were obtained by coprecipitation, by thermal treatment with acetylene-containing gas at 120 °C followed by hydrogen reduction at 180 °C. The characterization results of XRD, TEM, XPS, and H2-TPR measurements confirmed the presence of nickel carbide (Ni3C), copper carbide (CuxC), Cu, and Ni in the matrix of amorphous carbon in the composite catalyst. The mild preparation temperature and the porous carbon shell layers prevented the nano-sized particles from aggregation. The formation of interstitial Ni3C and CuxC significantly enhanced the dissociation of molecular hydrogen, accelerating the selective hydrogenation of 4-nitrophenol (4-NP) to yield 4-aminophenol (4-AP) at relatively mild conditions (80 °C and 1.0 MPa hydrogen pressure). The catalytic performance of the composite catalysts depended strongly on the Ni/Cu molar ratio, with an optimal Ni/Cu molar ratio of 4. In addition, the composite catalyst showed high conversion and selectivity to the corresponding aniline in the selective hydrogenation of other nitroarenes, including nitrobenzene, 4-nitrotoluene, 4-nitrochlorobenzene, 4-nitrobenzaldehyde, 4-nitroacetophenone, and 2-nitroaniline. The catalyst offers a novel approach to rational design and preparation of high-performance abundant metal catalysts for selective hydrogenation of nitroarenes.

Magnetic field-enhanced two-electron oxygen reduction reaction using CeMnCo nanoparticles supported on different carbonaceous matrices

The current study illustrates the successful synthesis of Ce1.0Mn0.9Co0.1 nanoparticles, characterized through XRD, EPR, magnetization curves, and TEM/HRTEM/EDX analyses. These nanoparticles were then loaded into the carbon Vulcan XC72 and the carbon Printex L6 matrices in varying amounts (1, 3, 5, and 10 % w/w) via wet impregnation method to fabricate electrocatalysts for the 2-electron ORR. Before experimentation, the material was characterized via XPS and contact angle measurements. The electrochemical results produced significant findings, indicating that the electrocatalysts with the nanostructures modifying both carbon blacks notably augmented currents in rotating ring-disk electrode measurements, signifying enhanced selectivity for H2O2 production. Moreover, our research underscored the significant impact of Magnetic Field-Enhanced Electrochemistry, employing a constant magnetic field strength of 2000 Oe, on 2-electron ORR experiments. Particularly noteworthy were the observed results surpassing the ones without the magnetic field, demonstrating heightened currents and improved selectivity for H2O2 production (more than 90 %) facilitated by CeMnCo nanoparticles. These significant findings in electrocatalytic efficiency have practical implications, suggesting the potential for developing more efficient and selective catalysts for the 2-electron ORR.

VBO3/V2O3@C heterogeneous anode material with high-specific-capacity and high-stability for lithium-ion batteries

The design and synthesis of high-performance anode materials is the key to further improve the performance of lithium-ion batteries. In this study, VBO3/V2O3 heterogeneous material with high crystallinity was prepared in vacuum quartz tubes by a facile high-temperature solid-phase method, and the electron transport capacity of VBO3/V2O3 was further improved by ball-milling with conductive carbon. As a result, the obtained VBO3/V2O3@C heterogeneous anode material delivers an initial discharge specific capacity of 927 mAh·g−1 and good cycling stability. Even at −20 °C, VBO3/V2O3@C still presents a discharge specific capacity of 432 mAh·g−1. In addition, ex-situ XRD and ex-situ XPS measurements reveal the conversion reaction and (de)intercalation reaction mechanism during charge/discharge. This work deepens the understanding of the structure-activity relationship of borate/oxide heterogeneous anode materials.

Bioactive modification of cyclic olefin copolymer (COC) film surfaces by hyaluronic acid and chitosan for enhanced cell adhesion

Cyclic olefin copolymer (COC) has recently emerged as an attractive material in biomedical fields for its high purity, excellent stability and chemical resistance, particularly in applications of microfluidic chips, prefilled syringes and bone regeneration. However, the high hydrophobicity of COC has inhibited the adhesion of cells and biological macromolecules, such as proteins, etc., significantly limiting its broader applications. In this study, we propose a new method to modify COC surfaces by sequential coating with polydopamine (PDA) followed by hyaluronic acid (HA) or O-carboxymethyl chitosan (CMC), while comparing the impacts of the positively charged HA and negatively charged CMC on protein adsorption and cell adhesion. FTIR and XPS measurements confirmed the successful modification on COC films, resulting in surfaces with highly increased hydrophilicity, anti-oxidative properties, and improved protein adsorption. Moreover, negatively charged HA, with signal transduction capabilities showed a greater effect in promoting cell adhesion. Thus, we present a straightforward strategy for enhancing the hydrophilicity of COC surfaces, offering new insights into COC modification and potential biomedical applications.

Magnetron sputtered ß-Ti coatings for biomedical application: A HiPIMS approach to improve corrosion resistance and mechanical behavior

This work presents the surface modification of commercially pure Ti specimens (c.p.-Ti) prepared by conventional powder metallurgy by depositing a thin film of a ß-Ti alloy (Ti-35Nb-7Zr-5Ta, wt. %, TNZT). Two types of pulsed technologies: conventional (p-DC) and high-power impulse magnetron sputtering (HiPIMS), with and without bias assistance (−60 V) under similar power conditions (250 W) were applied on titanium specimens and silicon substrates leading to different film morphologies and functional properties. Microstructural, X-ray diffraction, nanoindentation, surface wetting, XPS and electrochemical impedance measurements were done to characterize their functionality. All the coatings presented a reduced Young’s Modulus (E ≤ 80GPa) compared to the bulk Ti, representing a reduction of more than 30 %. This decrease can significantly contribute to the reduction of the stress-shielding effect, mitigating the risk of implant loosening and failure. The hardness values of TNZT coatings, slightly lower than c.p.-Ti substrate, range from 4.1 to 4.7 GPa. XPS analysis shows a passivation layer of TiO2, Nb2O5, and ZrO2, which offers high impedance and excellent corrosion resistance. The best compromise between mechanical and corrosion properties is achieved with the HiPIMS technology, thanks to its compact film microstructure with high electrical resistance, despite its limited thickness of about 1 μm.

Preparation of pigmentary grade bismuth vanadate Bi4V2O11 via coprecipitation method

ABSTRACT In this study, Bi4V2O11 pigments were synthesized using a coprecipitation method, and the pH value and calcination temperature were optimized from the viewpoint of red colorant. The obtained samples were characterized by XRF, XRD, Rietveld refinement, TEM, UV–vis diffuse reflectance spectrometry, SEM, XPS and color measurements. It was found that Bi4V2O11 samples with single-phase monoclinic structure could be prepared, when the calcination temperatures were 973 and 1073 K. The obtained single-phase Bi4V2O11 samples exhibited reddish hue. For the sample, which was prepared at pH = 7.0 and calcined at 973 K, its color coordinates were L* = 46.41, a* = +27.41, b* = +26.09.

Dual redox centers in MnCo2O4 nanorod cathode for highly efficient capacitive deionization

Capacitive deionization (CDI) technology via faradic electrodes with active redox pairs has achieved tremendous success in desalination. However, the inner collaborative mechanisms of multi-redox centers in electrodes are rarely deep-analyzed. Thus, this work intensively investigated the inner enhanced mechanisms of multi-redox centers, starting from the dual-redox-based MnCo2O4 nanorod (MCO-NR) cathode in capacitive desalination. The electrochemical tests indicated a surface capacitive ratio of MCO-NR as high as 86 % when the scan rate was 100 mV s−1. Multi-dimensional CDI tests demonstrated that the highest capacity of MCO-NR could reach 61.78 mg g−1, with four theory models elaborating the electrosorption kinetics and maximum desalination capability. The refined ex-situ XPS measurements, carefully designed comparative experiments, and DFT calculations were used to analyze the Na+ (de)intercalation characteristics, the inner enhanced electrosorption mechanisms of dual redox centers, and the effects that the Mn redox center exerts on the MnCo2O4 structure. These results showed the superiority of dual- or multi-redox-center-based faradic capacitive desalination, providing a new perspective for designing high-property faradic electrode materials.

Corrosion Inhibition of Carbon Steel in Neutral Chloride Solutions Using Salts of Primary Bile Acids.

Due to growing environmental concerns and regulatory pressures, the demand for environmentally friendly corrosion inhibitors has increased. Biosurfactants are biodegradable and have a low toxicity. However, very few studies have reported on their potential use as corrosion inhibitors. The present study reports the novel application of two bile salts (sodium cholate NaC and sodium chenodeoxycholate NaCDC) as environmentally friendly corrosion inhibitors for carbon steel in a neutral 20 mM NaCl solution. The results of potentiodynamic polarization and electrochemical impedance measurements showed that when added at a concentration of 5 mM, the corrosion inhibition efficiencies of NaC and NaCDC were about 60% and 85%, respectively. The poor inhibitory character of NaC was confirmed by XPS analysis, revealing the formation of oxidative corrosion products on the steel surface. For the steel sample immersed in the solution containing NaCDC, the XPS measurements showed clear evidence of the presence of an organic layer and a passive oxide film on the steel surface. While the steroidal skeleton of NaC is characterized by marked biplanarity (considering its hydrophobic and hydrophilic faces), NaCDC features a steroidal ring with a hydrophilic edge (it does not exhibit biplanarity). Thus, the self-assembly and adsorption behavior of these bile salts on the steel surface are different, leading in the case of NaCDC to form a densely packed protective organic layer.

Polymer coating by oxidative polymerization of a new dopamine analogue with two amino groups

In our quest to expand the comprehensive chemistry of polydopamine and its catechol-containing analogous adhesive polymers we developed a new monomer, specifically 4-[3-amino-2-(aminomethyl)propyl]benzene-1,2-diol ADA. This compound is an analogue of dopamine characterized by an elongated and branched alkyl side chain that incorporates two amino groups. ADA was synthesized in two steps from 3,4-dihydroxybenzaldehyde in high yields. Exposure to air in aqueous Tris solution initiated polymerization leading to a dark colored product PADA that can adhere to surfaces forming continuous layers. The product was analyzed by FTIR, NMR, UV–vis-spectroscopy, AFM, HR-ESI-MS spectrometry, XPS, DPV, DLS and contact angle measurement. Based on these analyses, a general structure of the product is proposed as along with a mechanism of its formation. Notably, the properties of PADA are distinct from those of polydopamine offering different potential application. In particular, the additional amino groups could be used for interesting linkage of other functional moieties.

Fabrication of recoverable plant polyphenol-based surfactants for efficient removal of uranyl ions from skin and cotton fabric

With the increasing demand for uranium in the nuclear industry, the unintended uranium contamination of skin or clothing for individuals involved in nuclear activities has raised public health concerns. Herein, a plant polyphenol-based surfactant (sulfonated bayberry tannin surfactant, SBTS) was fabricated by modifying the hydrophobic groups in the sulfonated bayberry tannin (SBT) structure using a simple Friedel–Crafts alkylation reaction. The surfactant modified with tetradecane chloride showed superior foaming ability and emulsifying properties compared with SBT. The characterization of SBTS by FT-IR spectroscopy confirmed that hydrophobic chains were successfully grafted on SBT molecules via covalent bonds. As expected, SBTS could disperse in water under near-neutral pH condition, and showed good foaming and emulsifying properties. Moreover, the surfactant exhibited effective removal ability for UO22+-contaminated cotton fabric and skin in a broad application range, reaching a removal rate of 99 % for low amounts of UO22+, and even above 55 % for high UO22+ amounts. More importantly, SBTS after reacing with UO22+ could be easily separated from aqueous systems after standing for 60 min in acidic and neutral conditions, which is a favorable feature to avoid secondary pollution. In vitro cytotoxicity tests suggested that SBTS was much safer than commonly used synthetic surfactants. Based on XPS and FT-IR measurements, we propose a decontamination mechanism mainly originating from the chelation effect between the phenolic hydroxyl group of SBTS and UO22+. This study highlights the potential of plant tannin surfactants as effective materials for the removal of UO22+ from skin or clothing of individuals involved in various nuclear-related activities.

Hydrothermally derived Cr-doped SnS2 layered nanoplates: investigation of their controlled structural, morphological, optical, magnetic, photo response and photocatalytic activities

A facile method has been employed to synthesize pristine and Cr-doped SnS2 (Cr: SnS2) nanoplates (Sn1-xCrxS2, here x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) and Cr: SnS2 nanoplates (NPs) were successfully synthesized via hydrothermal method. The nanoplates' structure was hexagonal, with a preference for orientation along the (001) plane; there was no evidence of additional undesirable phases. FTIR and EDX were used to observe the existence of functional groups in the samples where Sn-S bonds were present in each of the produced pristine and Cr: SnS2 nanoplates. XPS measurements demonstrated the existence of Sn, S, and Cr. FESEM revealed that the morphological properties of the nanoplates included several hexagonal grains. Magnetic characterizations showed that with increasing doping concentration of Cr, SnS2 nanoplates become superparamagnetic from ferromagnetic. The band gap values for the pristine and Cr: SnS2 nanoplates calculated from the absorbance spectra decreased from 2.53 to 2.08 eV with an increase in doping concentration. The photoluminescence spectra of the pristine SnS2 and Cr: SnS2 nanoplates exhibit two strong emission peaks at around 562 and 666 nm for an excitation wavelength of 420 nm. The Cr: SnS2 nanoplates have demonstrated the resistive behavior of the sample. The Cr: SnS2 nanoplates have shown good photocatalytic activity towards the decolorization of rhodamine B under visible irradiation.

Sol Gel obtained Ti/Co/Mn oxides doped with 5wt% CuO for the photocatalytic removal of organic azo dyes from wastewater

Various organic pollutants continually poison natural water resources due to rapid modernization driven by industrial growth. As a result, communities throughout the globe are paying close attention to the health and environmental issues raised by these harmful organic pollutants. Here, we prepared TiO2-CuO(5wt%), TiO2-CuO(5wt%)@Co3O4, and TiO2-CuO(5wt%)@Mn2O3 photocatalysts by employing the sol-gel method for the photocatalytic removal of azo dyes. These composites' surface morphology, composition, band gap, and purity were analyzed using SEM, EDS, TEM/HRTEM, XRD, FTIR, Raman, XPS, DRS, and BET measurements. The 5 % CuO doping caused a significant change in the electronic structure of the composites and contributed to the superior photocatalytic performance of the composites against azo dyes at neutral pH and under visible light irradiation. The function of reactive oxygen species (ROS) was also studied using different scavengers and enhancers; •OH was found to be the main ROS for the photodegradation of azo dyes.

A novel photoelectrochemical based water splitting and uric acid biosensing using PLD grown In2Se3 thin films

By altering the deposition pressure during the film growth process using the pulsed laser deposition (PLD) technology, indium selenide (In2Se3) thin films have been optimized to produce their distinct phases. The phase purity, optical and morphological studies were carried out using XRD, Raman spectroscopy, XPS, UV–visible spectroscopy, AFM and FESEM measurements. A high absorption in the visible region is observed for In2Se3 thin films with suitable band edges for hydrogen evolution. Photoelectrochemical (PEC) activity for In2Se3 photoelectrodes having various phases was analyzed based on CV and I-t response. A good charge transport characteristics were observed using the EIS measurements on PLD grown In2Se3 thin films. The Mott–Schottky analysis for the charge carrier density, flat band potential, and depletion layer width was performed for the deposition pressure dependent phase formation and high performance for PEC water splitting conversion efficiency of 0.48 %, 0.57 % and 0.98 % corresponding to α-In2Se3, β-In2Se3 and γ-In2Se3 were observed, respectively. The as prepared In2Se3 thin films were employed for the detection of Uric Acid (UA) using the cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. The high sensitivity (0.38 mA/mM), selectivity and repeatability of the prepared biosensor demonstrates In2Se3 as potential candidate for the PEC based water splitting and biosensing application without the presence of an external mediator and can work in the self-powered mode.