Selective Deactivation Research Articles

Gasoline production by oligomerization of 1-butene at low pressure: Kinetic model and reactor simulation

A five lump kinetic model (C4=, C8=, C12=, C1-C4 and C5-C12) has been established for 1-butene (C4=) oligomerization at low pressure (1.5 bar) and 275 °C on an HZSM-5 zeolite catalyst agglomerated in a γ-Al2O3 mesoporous matrix. The kinetic parameters have been calculated based on the results obtained in a packed-bed reactor for different concentrations of 1-butene in the feed (with N2 as diluent) and different values of space time (0.5–9.5 gcatalyst h molC-1). The model quantifies the evolution with time on stream of the concentrations of the lumps, considering the selective deactivation of the catalyst for the oligomerization, cracking and pool of secondary reactions. Furthermore, it allows to calculate the remnant activity of the catalyst in the pseudo-steady state (>5h on stream) for the different reaction groups, as well as the corresponding product distribution. The kinetic model has been used in the simulation of the packed-bed reactor to study the effect of space time and 1-butene partial pressure variables. At the conditions range studied experimentally, 39.4 % gasoline yield (C5-C12 fraction, mainly composed of olefins) and a 1-butene conversion of 45 % are achieved in the pseudo-steady state of the catalyst, at a space time of 9.5 gcatalyst h molC-1 and a partial pressure of 1-butene of 0.8 bar. Additionally, for values exceeding those studied experimentally, the model predicts at the pseudo-steady state a gasoline yield of 60 % at a space time of 30 gcatalyst h molC-1 and a partial pressure of 1-butene of ∼ 0.5 bar.

Carbon-dot/attapulgite composite sonocatalytic towards efficient indigo-containing wastewater degradation based on the cavitation mechanism

Catalytic degradation is an effective method to treat indigo carmine (IC) in wastewater, while high-performance catalyst materials need to be explored. Herein, a facile “spot-heating” synthesis method was employed, whereby the carbon dots (CDs) sonosensitizer was loaded onto the surface of attapulgite (ATP) with ultrasonic cavitation effect, resulting in a composite sonosensitizer ec-CDs/ATP (where ec-CDs represent CDs prepared from ethanol (e) and citric acid (c)). ATP served as a good carrier promotes uniform dispersion of CDs. Benefiting from the large specific surface area, more active sites on the surface of ec-CDs/ATP were exposed, which promotes efficient degradation performance for IC, with a 20 % improvement in performance compared to the reported pure CDs or composite CDs photocatalysts (Bi2O3/dots, Cl-dots). The selective deactivation reactions and relative characterizations further verify that the catalytic process is compatible with the sonocatalytic mechanism originating from the fracture of surface oxygen-containing groups. Importantly, ec-CDs/ATP with a small mass of CDs loading achieves the same catalytic performance as a large mass of pure CDs. This research innovatively presents a simple synthesis method of a composite CDs sonosensitizer and explores its mechanism of degradation, thus pointing the way to the design of multifunctional sonocatalysts for the degradation of IC in wastewater.

Effect of internal and external electron donors on stereospecific polymerization of isoprene with TiCl4/MgCl2 type Ziegler-Natta catalysts

Two TiCl4/MgCl2 type Ziegler-Natta catalysts containing ethyl benzoate (EB) and dibutyl phthalate (DBP) as internal electron donors (ID) were prepared for isoprene polymerizations using five kinds of external electron donors (ED) (phenyltrimethoxysilane (ED-1), dicyclopentyl(dimethoxy)silane (ED-2), 2-butyl-2-ethyl-1,3-dimethoxypropane (ED-3), 1,3-dimethoxypropane (ED-4) and di(2-ethylhexyl)phthalate (ED-5)). The structure features of TiCl4/ID/MgCl2 catalysts were characterized and the effect of ID and ED on polymerization behaviors was studied. EB had higher adsorption content on catalyst surface, higher catalytic activity and lower trans-1,4 stereoselectivity than DBP. Appropriate introduction of ED-1 and ED-2, expect ED-3, ED-4 and ED-5, caused the enhancement in polymerization activity and trans-1,4 content, while excess addition led to the deactivation. The effect of ED on equilibrium between selective activation and deactivation of active species significantly relied on the electron donor type and concentration.

Cu TSV Filling with Cetyltrimethyl Ammonium Cations (CTA+) and Br-

Through silicon via (TSV) technology is essential for the three-dimensional packaging of electronic devices. After creating high-aspect-ratio vias, Cu electrodeposition is performed to achieve defect-free Cu interconnection. The most important purpose of electrodeposition process is to fill the features without any defects, and this process is called superfilling, superconformal deposition, or bottom-up filling. Since TSV is a key component for the packaging of semiconductor devices, various research on the electrodeposition process for TSV filling have been studied. Defect-free TSV filling can be achieved by introducing appropriate organic/inorganic additives into the electrolyte and the filling performance can be promoted by pulse reverse electrodeposition.1-3 Generally, it has been reported that Cu bottom-up filling at TSVs can be obtained by three-additive combinations (suppressor, accelerator, and leveler) or by using a single suppressor. Tetronic 701 is the most representative suppressor in a single-additive filling method, which was based on S-shaped negative differential resistance (S-NDR) behavior.4-6 In the case of three-additive systems, various levelers that contained ammonium functional groups, a polymeric suppressor, and an accelerator have been researched.7,8 Furthermore, it has been reported that halide ions (Br- and I-) can act as levelers for inducing Cu bottom-up filling at TSVs.9,10 This study investigated the effects of cetyltrimethyl ammonium cation (CTA+) and halide ion on TSV filling in the presence of an accelerator and polymeric suppressor. The influences of two halide ions, Cl- and Br-, on the adsorption of CTA+ and their convection dependency were studied. This presentation will introduce the electrochemical behaviors of halide ions and CTA+ and defect-free filling using the optimum combination of these additives. References M. Hayase, and K. Otsubo. "Copper deep via filling with selective accelerator deactivation by a reverse pulse" J. Electrochem. Soc.,157, D628 (2010).Q.S. Zhu, X. Zhang, C.Z. Liu, and H.Y. Liu. "Effect of reverse pulse on additives adsorption and copper filling for through silicon via" J. Electrochem. Soc.,166, D3006 (2019)Q.S. Zhu, A. Toda, Y. Zhang, T. Itoh, and R. Maeda. "Void-free copper filling of through silicon via by periodic pulse reverse electrodeposition" J. Electrochem. Soc.,161, D263 (2014)T. P. Moffat, and D. Josell. "Extreme bottom-up superfilling of through-silicon-vias by damascene processing: suppressor disruption, positive feedback and turing patterns" J. Electrochem. Soc.,159, D208 (2012)D. Joell, and T. P. Moffat. "Superconformal copper deposition in through silicon vias by suppression-breakdown." J. Electrochem. Soc.,165, D23 (2018)M. Dong, Y. Zhang, T. Hang, and M. Li. "Structural effect of inhibitors on adsorption and desorption behaviors during copper electroplating for through-silicon vias." Electrochim Acta372 (2021)M. J. Kim, Y. Seo, J. H. Oh, Y. Lee, H. C. Kim, Y. G. Kim, and J. J. Kim. "Communication—halide ions in teg-based levelers affecting TSV filling performance." J. Electrochem. Soc.,163, D185 (2016)V. Q. Dinh, K. Kondo, V. H. Hoang, and T. Hirato. "Communication—Bottom-up TSV filling using sulfonated diallyl dimethyl ammonium bromide copolymer as a leveler." J. Electrochem. Soc.,166, D505 (2019)M. J. Kim, H. C. Kim, and J. J. Kim. "The influences of iodide ion on Cu electrodeposition and TSV filling." J. Electrochem. Soc.,163, D434 (2016)M. Sung, Y. Yoon, J. Hong, M. J. Kim, and J. J. Kim. "Bromide ion as a leveler for high-speed TSV filling." J. Electrochem. Soc., 166, D546 (2019) Figure 1

Selective deactivation of perovskite grain boundaries

Selective deactivation of perovskite grain boundaries

Evaluation of a clinical method for selective electrode deactivation in cochlear implant programming.

Cochlear implants are a neural prosthesis used to restore the perception of hearing in individuals with severe-to-profound hearing loss by stimulating the auditory nerve with electrical current through a surgically implanted electrode array. The integrity of the interface between the implanted electrode array and the auditory nerve contributes to the variability in outcomes experienced by cochlear implant users. Strategies to identify and eliminate poorly encoding electrodes have been found to be effective in improving outcomes with the device, but application is limited in a clinical setting. The purpose of this study was to evaluate a clinical method used to identify and selectively deactivate cochlear implants (CI) electrodes related to poor electrode-neural interface. Thirteen adult CI users participated in a pitch ranking task to identify indiscriminate electrode pairs. Electrodes associated with indiscriminate pairs were selectively deactivated, creating an individualized experimental program. Speech perception was evaluated in the baseline condition and with the experimental program before and after an acclimation period. Participant preference responses were recorded at each visit. Statistically significant improvements using the experimental program were found in at least one measure of speech perception at the individual level in four out of 13 participants when tested before acclimation. Following an acclimation period, ten out of 13 participants demonstrated statistically significant improvements in at least one measure of speech perception. Statistically significant improvements were found with the experimental program at the group level for both monosyllabic words (p = 0.006) and sentences in noise (p = 0.020). Additionally, ten participants preferred the experimental program prior to the acclimation period and eleven preferred the experimental program following the acclimation period. Results from this study suggest that electrode deactivation may yield improvement in speech perception following an acclimation period. A majority of CI users in our study reported a preference for the experimental program. This method proved to be a suitable clinical strategy for identifying and deactivating poorly encoding electrodes in adult CI users.

Mathematical Model for the Industrial SMTO Reactor with a SAPO-34 Catalyst.

The methanol-to-olefins (MTO) technology creates a new non-oil route to produce light olefins. This paper reports a 14-lump MTO kinetic model for SAPO-34 catalyst, combined with the hydrodynamic model for the fast fluidized bed reactor of the industrial SMTO process. Selective deactivation is considered to quantify the product selectivity and abrupt catalytic activity change. Moreover, referring to the parallel compartment (PC) model, the activity difference between the circulating spent catalyst and the regenerated catalyst is considered. The validation results with the optimized kinetic parameters showed good agreement between the calculated value and the actual value. Sensitivity analysis of the industrial SMTO process was performed. According to the results, the established mathematical model can provide guidance for industrial production operations.

Survey of selective electrode deactivation attitudes and practices by cochlear implant audiologists

Objectives The purpose of this study was to explore clinician attitudes regarding selective electrode deactivation and to investigate the primary methodology used to identify poorly encoded electrodes, deactivate identified electrodes, and measure outcomes. Methods An online survey consisting of 32 questions was administered to certified clinical and research cochlear implant (CI) audiologists. Questions asked participants about their demographic information, device programming patterns, and attitudes regarding selective electrode deactivation. Results Fifty-four audiologists completed the survey. When asked whether they believed selectively deactivating poorly encoded electrodes could improve speech perception outcomes, 43% of respondents selected ‘Probably Yes,’ 39% selected ‘Definitely Yes,’ and 18% selected ‘Might or Might Not.’ Of those who reported deactivating electrodes as part of CI programming, various methodology was reported to identify and deactivate poorly encoding electrodes and evaluate effectiveness of deactivation. General reasons against deactivation were also reported. Discussion CI audiologists generally believed selective electrode deactivation could be used to improve speech perception outcomes for patients; however, few reported implementing selective electrode deactivation in practice. Among those who do perform selective electrode deactivation, the reported methodology was highly variable. Conclusion These findings support the need for clinical practice guidelines to assist audiologists in performing selective electrode deactivation.

EFEITO DOS DEFEITOS DE SUPERFÍCIE E DO pH NA ADSORÇÃO E NA CATÁLISE DA ELETRO-OXIDAÇÃO DE CO EM SUPERFÍCIES MODELOS DE PLATINA

SURFACE DEFECTS AND pH EFFECTS ON ADSORPTION AND CATALYSIS OF CO ELECTRO-OXIDATION ON MODEL PLATINUM SURFACES. Platinum is one of the well-known catalytic materials for which the electro-oxidation of carbon monoxide better behaves as a sensitive reaction to the catalyst surface structure. For the electro-catalytic reactions that behave like this, the rate (faradaic current density) is the result of the sum of the activity of the different active sites working with very different efficiencies or abilities. In this scenario, different atomic arrangements on the catalyst surface are expected to play different roles in surface-catalyzed reactions. In this article, the functionalities that surface defects (steps) can play in the adsorption and electrocatalytic oxidation of CO on model platinum surfaces are reviewed. Surface defects are indirectly related to the up catalysis as well as to the inhibition of reaction pathways of CO electro-oxidation under very particular conditions; these surface entities are also indirectly related to restrictions for the mobility of adsorbed CO on the (111) terraced surfaces. We analyze the selective activation and deactivation of surface sites by the pH effect, and typical catalytic properties of extended surfaces and shaped-controlled nanoparticles have been discussed thoroughly. We present a model of most active sites involved in the pathways of CO2 formation from the electro-oxidation of adsorbed CO.

БИЛАТЕРАЛЬНЫЙ ОБЛИК СУВЕРЕНИТЕТА В ЗЕРКАЛЕ НАУЧНОЙ ДИСКУССИИ

The fact that the evolution of the “political world” occurs together with the transformation of its conceptual and categorical apparatus does not cause serious doubts. Today, the process of irreversible changes in the area has affected the concept of sovereignty as basic for the social sciences. The article found that alternative views on the bilateral structure of sovereignty make the content of that concept more voluminous and require the use of additional tools to facilitate its understanding. One of the evidences of such state of affairs is the classification of sovereignty by S. Krasner, which is common in political science. A critical analysis of S. Krasner’s typology, however, could not secure for the typology of the famous scientist the adherence to the basic scientific principle – objectivity. Overcoming the author’s subjectivity which stimulated the selective deactivation of one of the two sides of sovereignty it was decided to theoretically construct special approaches to understanding sovereignty. A more rigorous matrix, known in political science by the phrase “The Great Debates”, was used to identify supporters/opponents of each of the formed approaches, as well as to describe the difference in their research positions. The use of the matrix of Great Debates in accordance with the axiomatic method became an example of a not unsuccessful attempt to implement methodological triangulation, which updated the versatile “vision” of sovereignty and stimulated a more comprehensive view of it

The Ethics of Memory Modification: Personal Narratives, Relational Selves and Autonomy

For nearly two decades, ethicists have expressed concerns that the further development and use of memory modification technologies (MMTs)—techniques allowing to intentionally and selectively alter memories—may threaten the very foundations of who we are, our personal identity, and thus pose a threat to our well-being, or even undermine our “humaneness.” This paper examines the potential ramifications of memory-modifying interventions such as changing the valence of targeted memories and selective deactivation of a particular memory as these interventions appear to be at the same time potentially both most promising clinically as well as menacing to identity. However, unlike previous works discussing the potential consequences of MMTs, this article analyzes them in the context of the narrative relational approach to personal identity and potential issues related to autonomy. I argue that such a perspective brings to light the ethical aspects and moral issues arising from the use of MMTs that have been hidden from previously adopted approaches. In particular, this perspective demonstrates how important the social context in which an individual lives is for the ethical evaluation of a given memory-modifying intervention. I conclude by suggesting that undertaking memory modifications without taking into account the social dimension of a person’s life creates the risk that she will not be able to meet one of the basic human needs—the autonomous construction and maintenance of personal identity. Based on this conclusion, I offer some reflections on the permissibility and advisability of MMTs and what these considerations suggest for the future.

Identification of the Kinetic Parameters of Thermal Micro-Organisms Inactivation

A mathematical model for estimating the characteristics of the process of thermal inactivation of vegetative bacterial cells and their spores is presented. The model relates the change rate of the number of living cells as a nonlinear kinetic dependence of the p-th order, and the temperature constant of their inactivation rate is the Arrhenius function. A method for solving the inverse kinetic problem of identifying the parameters of this model from experimental data is proposed. The method is implemented through the minimization of the original functional, which reduces the number of variable parameters. The solution results of inverse problems for determining the kinetic model parameters based on the experimental data of thermal inactivation of bacterial spores B. subtilis and B. anthracis are presented. The obtained parameters are used to solve the direct problems of the dynamics of micro-organism inactivation. The calculation results represent the dependence on the time of the change number of inactivated micro-organisms, and the thermal exposure time for 99% of their deaths at different temperatures. A comparison of the results with other authors’ calculations and experimental data confirms the adequacy of the model, the high accuracy of the new solution method and the algorithm for its implementation. The developed model of thermal sterilization can be used for the selective deactivation of pathogens in the food products.

Hexafluoroisopropanol for the Selective Deactivation of Poisonous Nucleophiles Enabling Catalytic Asymmetric Cyclopropanation of Complex Molecules

In the presence of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), nucleophilic and reactive reagents are prevented from interacting with a rhodium carbene, allowing asymmetric cyclopropanation to occur with high yield and stereoselectivity on a variety of compounds. A high-throughput screen was conducted on cyclopropanation with a complementary catalytic system in the presence of 90 different poisonous nucleophiles and varying amounts of HFIP (10 equiv, used as reaction solvent). The scope of both the aryl/heteroaryl diazoacetate and the olefin was expanded, and the study culminated in the enantioselective functionalization of complex molecules including API and natural products.

Controlling the Fe2O3–SiO2 interaction: The effect on the H2S selective catalytic oxidation and catalyst deactivation

Biogas utilization is one of the most promising options for reducing the consumption of fossil fuels for energy production, but the presence of H2S represents a serious industrial and environmental problem. In this work, two different synthesis methods (sol-gel and incipient wetness impregnation) were used to synthesize iron oxide supported on silica catalysts (Fe2O3/SiO2) with metal loadings ranging from 0.5 to 10 %wt. The catalysts were tested for the selective oxidation of H2S, changing the operating conditions like O2/H2S (0.5–2.5), temperature (170–250°C), and water content (0–50%). The optimum condition was O2/H2S = 0.5 and no water at 230 °C with the conversion of approximately 100%, the selectivity of 97%, and the deactivation of 0.6%. A detailed characterization of the fresh and spent catalysts’ surface revealed the presence of four deactivation mechanisms: metal surface reduction, oxygen vacancy loss, pore plugging, and sintering. Among the observed deactivation mechanisms, the sintering showed the highest impact on catalytic activity and deactivation. The sol-gel catalysts (SG) showed the highest metal-oxide/support interaction, which reduced the metal-oxide nanoparticles sintering compared with the incipient wetness impregnation method (IWI), reporting a lower sintering, higher activity, and selectivity, lower deactivation rates and lower sensitivity to the operating conditions. A catalytic cycle representing the possible surface intermediate states of the catalyst is proposed based on the performance and characterization results obtained.

Accelerating catalyst development for biofuel production through multiscale catalytic fast pyrolysis of biomass over Mo2C

Advanced catalytic materials play an enabling role in producing renewable fuels and chemicals from biomass, thereby helping meet the global climate-change goals set forth by the Intergovernmental Panel on Climate Change. Herein, we present a multiscale approach to accelerate the catalyst-process development cycle for catalytic fast pyrolysis (CFP) of biomass over Mo 2 C. Mo 2 C has been shown to possess co-localized acidic and metallic sites and exhibit high activity for deoxygenation of biomass pyrolysis model compounds. However, critical knowledge gaps remain regarding the effectiveness of this catalyst for CFP of whole biomass. We address these knowledge gaps and demonstrate that Mo 2 C is effective at deoxygenating biomass-pyrolysis products in the presence of H 2 but that it undergoes rapid selective and non-selective deactivation. The knowledge gaps addressed from this integrated study, targeting appropriate experiments across scales and feed types, enabled identification of critical modifications for advancing the CFP catalyst-process development cycle. • A multiscale evaluation of Mo 2 C for biomass catalytic fast pyrolysis is performed • Mo 2 C exhibits both selective and non-selective deactivation with whole biomass • Process and catalyst modifications are proposed for reducing deactivation • Model compound studies are essential but insufficient at predicting performance Catalytic fast pyrolysis (CFP) of biomass is an attractive process for producing bio-oils that can be further refined into fuels and chemicals, thus helping to reduce greenhouse-gas emissions. To meet the emissions reduction goals set forth by the Intergovernmental Panel on Climate Change, catalysts and processes for generating renewable products need to be rapidly designed and developed, calling for an accelerated catalyst-process development timeline. However, in the case of CFP, biomass pyrolysis produces a complex stream involving hundreds of molecules with multifunctional groups, steam, and metal impurities, which makes catalyst design challenging. This integrated study on biomass CFP over a promising multifunctional catalyst, Mo 2 C, addresses knowledge gaps critical to accelerating development of this catalyst and process. The intended outcome is to share lessons learned toward accelerating catalyst-process development cycles for systems with similar complex reaction chemistries. Accelerating the catalyst-process development cycle for complex chemistries, especially biomass processing, requires multiscale studies spanning model compound experiments to integrated, bench-scale tests with realistic feedstocks.

Synthesis of a Spatially Confined, Highly Durable, and Fully Exposed Pd Cluster Catalyst via Sequential Site-Selective Atomic Layer Deposition

Bottom-up synthesis based on site-selective atomic layer deposition is a powerful atomic-scale processing approach to fabricate materials with desired functionalities. Typical selective atomic layer deposition (ALD) can be achieved using selective activation of a growth area or selective deactivation of a protected area. In this work, we explored the site selectivity based on the difference of the inherent surface reactivity between different materials and within the same materials. By sequentially applying two site-selective atomic layer deposition, the ALD Pd catalyst is spatially confined on ALD SnO2 modified h-BN substrate Pd/SnO2/h-BN shows improved catalytic activity and stability due to strong metal-support interactions and spatial confinement. The results reveal that sequential site-selective ALD is a feasible and effective synthesis strategy that provides an attractive path toward designing and developing highly stable catalysts.

Practical Method for Burner Staging Turbine Forced Response Evaluation

Abstract Decarbonization and sustainability efforts challenge gas turbine engineers to come up with creative strategies for reduction of emissions and efficiency increase over the whole operating range. Burner staging at part loads presents a flexible solution to achieve these goals through selective burner deactivation. Shutting off burners could also be required for combustion of increased H2 content at some conditions. Burner staging will create circumferential unevenness with patterns of hot and cold streaks that could excite blade rows through the entire turbine. This paper presents a parametric method for annular combustor staging patterns' profile generation intended for use for forced response predictions from a limited number of combustor computational fluid dynamics (CFD) calculations while keeping the key phenomenological features. Two cases with burner staging turbine inlet temperature (TIT) distributions are considered and compared to a base case with uniform temperature distribution. The unsteady aerodynamic forcing was obtained from full wheel time marching unsteady CFD calculations. The results show that the hot streaks generate important and noticeable excitation sources. Additionally, the results show that the pattern generator could be used extensively before and after the unsteady calculations' phase to minimize the excitation levels and the computational load.

The Importance of the Transcription Factor Foxp3 in the Development of Primary Immunodeficiencies.

Transcription factors are an extremely important group of proteins that are responsible for the process of selective activation or deactivation of other cellular proteins, usually at the last stage of signal transmission in the cell. An important family of transcription factors that regulate the body’s response is the FOX family which plays an important role in regulating the expression of genes involved in cell growth, proliferation, and differentiation. The members of this family include the intracellular protein Foxp3, which regulates the process of differentiation of the T lymphocyte subpopulation, and more precisely, is responsible for the development of regulatory T lymphocytes. This protein influences several cellular processes both directly and indirectly. In the process of cytokine production regulation, the Foxp3 protein interacts with numerous proteins and transcription factors such as NFAT, nuclear factor kappa B, and Runx1/AML1 and is involved in the process of histone acetylation in condensed chromatin. Malfunctioning of transcription factor Foxp3 caused by the mutagenesis process affects the development of disorders of the immune response and autoimmune diseases. This applies to the impairment or inability of the immune system to fight infections due to a disruption of the mechanisms supporting immune homeostasis which in turn leads to the development of a special group of disorders called primary immunodeficiencies (PID). The aim of this review is to provide information on the role of the Foxp3 protein in the human body and its involvement in the development of two types of primary immunodeficiency diseases: IPEX (Immunodysregulation Polyendocrinopathy Enteropathy X-linked syndrome) and CVID (Common Variable Immunodeficiency).

Rapid area deactivation for blocking atomic layer deposition processes using polystyrene brush layers

This work illustrates the use of polystyrene brushes for area selective deactivation against a hafnium atomic layer deposition process. The effect that the thickness of this brush has on its ability to block this process is also shown.

Cube-Shaped GaN UV Photodetectors Using 3D-Printed Panels for Omnidirectional Detection

In this study, we designed and developed a hexahedral ultraviolet (UV) photodetector using three-dimensional (3D) printing. Furthermore, we demonstrated the proposed photodetector's functionality (omnidirectional UV detection) using photosensitive gallium nitride (GaN). To fabricate the cube (regular hexahedron), six panels were separately 3D-printed; a GaN UV photodetector was then mounted onto each panel during assembly. Given that the hexahedral photodetector had six sensors, the change in current for each sensor was distinct based on the angle of incidence of UV light; consequently, the UV source could be easily traced. Compared to conventional solar sensors, the proposed novel photodetector could estimate the various locations of the UV source through selective activation and deactivation. Optical and electrical characterization revealed high absorption of the UV spectra (near 370 nm), high signal-to-noise values (47-70), and rapid response times (0.4-0.8 s). This study demonstrates the feasibility of the design and fabrication-using 3D printing technology-of optical sensors for the multiple detection of incident UV light during navigation in various environments such as outer space, oceans, and subterranean environments.