Single Platinum Research Articles

Optimizing cooperative catalysis of multiple defective interfaces in Pt/mullite catalysts for NO oxidation

Nitric oxide (NO) oxidation is an integral part of the nitrogen chemical cycle, but competitive activation of NO/O2 over single platinum (Pt)-based catalysts result in inadequate low temperature performance. Here, we constructed catalysts with BiMn2O5/CeO2 and Pt/BiMn2O5 defective interfaces (sufficient activation of NO/O2). The constructed catalyst achieved 95 % NO conversion at 260 °C in NO/O2 atmosphere, superior to most known catalysts. Even after aging (800 °C for 16 h), the NO conversion was up to 76 %. Further, the catalyst can be applied to actual diesel exhaust. Detailed oxygen vacancies (Ov) characterization reveals that BiMn2O5/CeO2 defective interface created by Ce3+-Ov + Mn4+-O ↔ Ce4+-O + Mn3+-Ov promote the activation of NO (on Mn3+ sites) and O2 (on Mn3+-Ov sites). Besides, the Ov on Pt/BiMn2O5 defective interface compensate for the loss of Pt sites ensuring hydrothermal stability. And this construction of multiple defective interfaces develops a pathway for boosting catalytic reactions.

The Heterogeneity of Turn-over Number in Electrocatalysis

Chemical catalysts dominate the multi-billion global revenue of the chemical industry because they accelerate the time it takes a particular reaction to reach equilibrium without altering the equilibrium constant. Electrocatalysis can provide significant benefits compared to other methods, as it has minimal purification and separation costs, is operational at low temperatures and pressures, replaces hazardous and toxic chemical sources with electric current, and can be integrated with renewable energy sources. From a techno-economical point of view, some considerations are critical during a catalyst design: cost, activity, and durability. One useful metric to quantify catalyst durability is turn-over number (TON), which represents the maximum yield of products attainable from a catalytic center. Mathematically speaking, the TON is defined as: TON = ∫0 ∞ TOF(t) dt, where TOF is the turn-over frequency, which is the rate of turn-overs (N) per active site. Currently, without any exception, the TON is given as a fixed number describing the total amount of substrate converted until the catalysts fully degrade. Our approach studies electrocatalytic deactivation processes at the single catalyst level using a technique entitled single-entity electrochemistry for freely diffusing catalysts. The hydrogen evolution reaction (HER) is investigated with platinum nanoparticles as the model catalyst because it deactivates at the nanoscale when the catalytic activity decreases over time. At specific applied potentials, the current measured when a single platinum nanoparticle impacts the electrode creates a transient spike and decay back to the baseline current. TON is quantified by fitting the current decay response and integrating above the fit to find the charge transferred to catalyze the reaction. Our results show that electrocatalyst degradation and TON have a distribution, where some catalysts are more stable than others, and depends on the applied potential and size of the nanoparticles. In order to study how the surface facets of platinum affect the TON, SECCM was coupled with scanning electron microscopy (SEM) to compare the deactivation of a polycrystalline platinum surface in the macro scale with immobilized platinum nanoparticles on a glassy carbon surface. Combining local structural, electrochemical activity, and durability will bridge our fundamental understanding of macro and nanoscale catalyst deactivation processes to assist in the bottom-up approach of material development and design of large-scale industrial electrocatalysts.

Directional Growth and Density Modulation of Single‐Atom Platinum for Efficient Electrocatalytic Hydrogen Evolution

AbstractDispersion of single atoms (SAs) in the host is important for optimizing catalytic activity. Herein, we propose a novel strategy to tune oxygen vacancies in CeO2−X directionally anchoring the single atom platinum (PtSA), which is uniformly dispersed on the rGO. The catalyst's performance for the hydrogen evolution reaction (HER) can be enhanced by controlling different densities of CeO2‐X in rGO. The PtSA performs best optimally densified and loaded on homogeneous and moderately densified CeO2‐X/rGO (PtSA−M−CeO2−X/rGO). It exhibited higher activity in HER with an overpotential of 25 mV at 0.5 M H2SO4 and 33 mV at 1 KOH than that of almost reported electrocatalysts. Furthermore, it exhibited stability for 90 hours at −100 mA cm−2 in 1 KOH and −150 mA cm−2 in 0.5 M H2SO4 conditions, respectively. Through comprehensive experiments and theoretical calculations, the suitable dispersion density of PtSA on the defects of CeO2−X with more active sites gives the potential for practical applications. This research paves the way for developing single‐atom catalysts with exceptional catalytic activity and stability, holding promise in advanced green energy conversion through defects engineering.

Directional Growth and Density Modulation of Single-Atom Platinum for Efficient Electrocatalytic Hydrogen Evolution.

Dispersion of single atoms (SAs) in the host is important for optimizing catalytic activity. Herein, we propose a novel strategy to tune oxygen vacancies in CeO2-X directionally anchoring the single atom platinum (PtSA), which is uniformly dispersed on the rGO. The catalyst's performance for the hydrogen evolution reaction (HER) can be enhanced by controlling different densities of CeO2-X in rGO. The PtSA performs best optimally densified and loaded on homogeneous and moderately densified CeO2-X/rGO (PtSA-M-CeO2-X/rGO). It exhibited higher activity in HER with an overpotential of 25 mV at 0.5 M H2SO4 and 33 mV at 1 KOH than that of almost reported electrocatalysts. Furthermore, it exhibited stability for 90 hours at -100 mA cm-2 in 1 KOH and -150 mA cm-2 in 0.5 M H2SO4 conditions, respectively. Through comprehensive experiments and theoretical calculations, the suitable dispersion density of PtSA on the defects of CeO2-X with more active sites gives the potential for practical applications. This research paves the way for developing single-atom catalysts with exceptional catalytic activity and stability, holding promise in advanced green energy conversion through defects engineering.

Theoretical study of structure sensitivity on ceria-supported single platinum atoms and its influence on carbon monoxide adsorption.

Density functional theory (DFT) calculations explore the stability of a single platinum atom on various flat, stepped, and defective ceria surfaces, in the context of single-atom catalysts (SACs) for the water-gas shift (WGS) reaction. The adsorption properties and diffusion kinetics of the metal strongly depend on the support termination with large stability on metastable and stepped CeO2(100) and (210) surfaces where the diffusion of the platinum atom is hindered. At the opposite, the more stable CeO2(111) and (110) terminations weakly bind the platinum atom and can promote the growth of metallic clusters thanks to fast diffusion kinetics. The adsorption of carbon monoxide on the single platinum atom supported on the various ceria terminations is also sensitive to the surface structure. Carbon monoxide weakly binds to the single platinum atom supported on reduced CeO2(111) and (211) terminations. The desorption of the CO2 formed during the WGS reaction is thus facilitated on the latter terminations. A vibrational analysis underlines the significant changes in the calculated scaled anharmonic CO stretching frequency on these catalysts.

Unveiling the effect of solvent for hydrogen evolution in Pt-doped MXenes and corresponding high-entropy phase

Effect of solvent at the water/solid interface plays a non-negligible role in chemical reactions. Explicit solvation has been proved for its important effect on thermodynamics and kinetics of catalytic reactions. However, systematic studies about this perspective are still absence. In this work, using the model of single platinum atom immobilized on the metal vacancies of a series of MXenes, we systematically investigate the implicit/explicit solvent effect on their catalytic performance of the hydrogen evolution reaction (HER). We find that the solvent effect plays a significant role in affecting the calculation results for some systems. For TiNbC–PtNb, the value of ΔGH* decreases from −0.121 to −0.511 (−0.583) eV when considering implicit (explicit) correction, implying the decisive role of solvent effect for calculating HER in this system. Bader charge analysis and AIMD simulations reveal that TiNbC–PtNb surface is sensitive to H2O, thus causing this abnormal case. Surprisingly high-entropy phases of MXene overall are less sensitive to solvent compared to the pure phases, which could be due to their alloyed lattice with a strong ability against electronic and lattice fluctuations induced by solvent. Several systems like V2C–PtV, TiMoC–PtMo, and VNbC–PtV are predicted to be excellent electrocatalysts for alkaline HER with the appropriate Gibbs free energy of hydrogen adsorption and kinetic barrier of water dissociation. The perspective exemplified in this work highlights that more feasible operando should be considered, e.g., influence of water, to better simulate the reaction process. Our work suggests that Pt-doped MXenes are perfect systems for hosting atomic catalyst as well.

Controlling the Collision Type and Frequency of Single Pt Nanoparticles at Chemically Modified Gold Electrodes.

Studying the electrochemical response of single nanoparticles at an electrode surface gives insight into the dynamic and stochastic processes that occur at the electrode interface. Herein, we investigated single platinum nanoparticle collision dynamics and type (elastic vs inelastic) at gold electrode surfaces modified with self-assembled monolayers (SAMs) of varying terminal chemistries. Collision events are measured via the faradaic current from catalytic reactions at the Pt surface. By changing the terminal, solution-facing group of a thiolate monolayer, we observed the effect of hydrophobicity at the solution-electrode interface on single-particle collisions by employing either a hydrophobic -CH3 terminal group (1-hexanethiol), a hydrophilic -OH terminal group (6-mercaptohexanol), or an equimolar mixture of the two. Changes in the terminal group lead to alterations in collision-induced current magnitude, collisional frequency, and the distinct shape of the collision event current transient. The effects of the terminal group of the SAM were probed by measuring quantitative differences in the events monitored through both the hydrogen evolution reaction (HER) and hydrazine oxidation. In both cases, a platinum nanoparticle (PtNP) favors adsorption to bare and hydrophilic surfaces but demonstrates elastic collision behavior when it collides with a hydrophobic surface. In the case of a mixed monolayer, distinct characteristics of hydrophobic and hydrophilic surfaces are observed. We report how single nanoparticle collisions can reveal nanoscale surface heterogeneity and can be used to manipulate the nature of single-particle interactions on an electrode surface by functionalized self-assembled monolayers.

Single platinum atoms on TiO2 photocatalysts for acetaldehyde oxidation under visible-light irradiation

The effects of incorporation of various amounts of Pt into TiO2 photocatalysts on the removal of acetaldehyde under visible light and 60% RH were investigated. Pt at 0.096 wt% boosted the photocatalytic efficiency of TiO2, while further increased Pt amount resulted in a decrease in activity. The enhanced activity can be ascribed to small amounts of Pt and dispersed individual Pt atoms on TiO2. Furthermore, among the 0.096 wt% Pt-TiO2 samples with diverse annealing temperatures (100, 130, 200, 375, and 525 °C), the 130 °C annealed sample exhibited the highest activity at various humidity values (0, 30, and 60% RH). This superior performance can be attributed to its unique single-Pt-atom structure coordinated with ammonia or ammonium species on a TiO2 lattice, as evidenced by TOF-SIMS results. Our findings show how unique photocatalytic structures alter catalytic activity by controlling Pt content and annealing temperatures, which will be critical for real-world applications.

Optically Imaging In Situ Effects of Electrochemical Cycling on Single Nanoparticle Electrocatalysis.

Single-nanoparticle studies often need one or a series of nanoparticle populations that are designed with differences in a nominally particular structural parameter to clarify the structure-activity relationship (SAR). However, the heterogeneity of various properties within any population would make it rather difficult to approach an ideal one-parameter control. In situ modification ensures the same nanoparticle to be investigated and also avoids complicating effects from the otherwise often needed ex situ operations. Herein, we apply electrochemical cycling to single platinum nanoparticles and optically examine their SAR. An electrocatalytic fluorescent microscopic method is established to evaluate the apparent catalytic activity of a number of single nanoparticles toward the oxygen reduction reaction. Meanwhile, dark-field microscopy with the substrate electrode under a cyclic potential control is found to be able to assess the electrochemically active surface area (ECSA) of single nanoparticles via induced chloride redox electrochemistry. Consequently, nanoparticles with drastically increased catalytic activity are discovered to have larger ECSAs upon potential regulation, and interestingly, there are also a few particles with decreased activity, as opposed to the overall trend, that all develop a smaller ECSA in the process. The deactivated nanoparticles against the overall enhancement effects of potential cycling are revealed for the first time. As such, the SAR of single nanoparticles when subjected to an in situ structural control is optically demonstrated.

Organometallic Synthesis of High-density Pt Single Atom Catalyst on Nickel for Alkaline Hydrogen Evolution Reaction

Single atom platinum catalysts, characterized by isolated Pt atoms dispersed on suitable supports, exhibit high hydrogen evolution catalytic mass activity. The activity is usually limited by the low density of...

Reversibly sensitizing-storing-releasing 1O2 within a single platinum(II)-acetylide-based metallacycle molecule via laser power modulation

Reversibly sensitizing-storing-releasing 1O2 within a single platinum(II)-acetylide-based metallacycle molecule via laser power modulation

Spatial Structure Engineering of Interactive Single Platinum Sites toward Enhanced Electrocatalytic Hydrogen Evolution

AbstractRegulating site‐to‐site interactions between active sites can effectively tailor the electrocatalytic behavior of single‐atom catalysts (SACs). The conventional SACs suffer from low density of single atoms and lack of site‐to‐site interactions between them. Herein, a series of interactive Pt SACs with controllable Pt–Pt spatial correlation degree and local coordination environment is developed by integrating densely populated Pt single atoms in the sub‐lattice of a Co3O4 matrix. The obtained interactive Pt‐Co3O4 catalysts demonstrate remarkable electrocatalytic performance toward hydrogen production, outperforming those of isolated single atom‐ and nanoparticle‐based catalysts. The intrinsic catalytic activity of interactive Pt‐Co3O4 catalysts is closely dependent on the spatial structure of Pt sites with the adjusted d‐band center by regulating contents and atomic configuration of Pt sites. This work provides fundamental insights for the structure‐property relationship on interactive single active sites, which is expected to direct the rational design of highly efficient SACs.

Einbau von (Bioaktiven) Äquatorialen Liganden in Platin(IV)-Komplexe.

AbstractPlatin(IV)‐Prodrugs sind aufgrund ihrer erhöhten Tumorselektivität und geringeren Nebenwirkungen äußerst interessante Alternativen zu Platin(II)‐Antitumortherapeutika. Im Gegensatz zur gängigen Theorie haben wir kürzlich beobachtet, dass äquatoriale Liganden von z. B. Oxaliplatin(IV)‐Komplexen unter Bildung von [(DACH)Pt(OHeq)2(OAcax)2] hydrolysiert werden können. In der hier vorgestellten Arbeit untersuchten wir die Reaktivität und synthetische Verwendbarkeit dieses Komplexes, als Vorstufe für die Entwicklung neuartiger Platin(IV)‐Komplexe, welche mit herkömmlichen Methoden nicht zugänglich sind. Tatsächlich war es möglich die äquatorialen Hydroxidoliganden z. B. durch ein oder zwei monodentate Biotin‐Liganden, die unter Standardmethoden oxidiert werden würden, zu ersetzen. Die gebildeten Komplexe erwiesen sich als sehr stabil und zeigten auch nach der Reduktion eine langsame Ligandenfreisetzung, eine ideale Eigenschaft für lang zirkulierende zielgerichtete Strategien. Daraufhin wurden zwei Platin(IV)‐Komplexe mit äquatorialen Maleimiden, für die Bindung an Serumalbumin als natürlichen Nanocarrier, synthetisiert. Die Komplexe zeigten im Vergleich zu Oxaliplatin eine stark verlängerte Plasmahalbwertszeit und eine deutlich verbesserte Antitumoraktivität in vivo. Zusammenfassend ermöglicht diese neu entwickelte Syntheseplattform den einfachen und gezielten Einbau äquatorialer Liganden in Platin(IV)‐Komplexe. Des Weiteren können verschiedene (bioaktive) Einheiten koordiniert werden, wodurch sogar zielgerichtete dreifach‐wirksame Platin(IV)‐Prodrugs mit nur einem Platinzentrum möglich wären.

Insertion of (Bioactive) Equatorial Ligands into Platinum(IV) Complexes.

Platinum(IV) prodrugs are highly interesting alternatives to platinum(II) anticancer therapeutics due to their increased tumor selectivity and reduced side effects. In contrast to the established theory, we recently observed that the equatorial ligand(s) of e.g. oxaliplatin(IV) complexes can be hydrolyzed with formation of [(DACH)Pt(OHeq )2 (OAcax )2 ]. In the work presented here, we investigated the reactivity and synthetic usability of this complex to be exploited as a precursor for the development of novel platinum(IV) complexes, not able to be synthesized by conventional protocols. Indeed, we could substitute the equatorial hydroxido ligand(s) e.g. by one or two monodentate biotin ligands (which would be oxidized under standard methods). The formed complexes turned out to be very stable with slow ligand release after reduction, ideal for long-circulating tumor-targeting strategies. Therefore, two platinum(IV) complexes with equatorial maleimides, capable of exploiting serum albumin as a natural nanocarrier, were synthesized as well. The complexes showed massively prolonged plasma half-life and distinctly improved anticancer activity in vivo compared to oxaliplatin. Taken together, the newly developed synthetic platform allows the simple and specific insertion of equatorial ligands into platinum(IV) complexes. This will enable the attachment of three different (bioactive) moieties generating targeted triple-action platinum(IV) prodrugs within one single platinum complex.

Toward Quantum Chemical Free Energy Simulations of Platinum Nanoparticles on Titania Support.

Platinum nanoparticles (Pt-NPs) supported on titania surfaces are costly but indispensable heterogeneous catalysts because of their highly effective and selective catalytic properties. Therefore, it is vital to understand their physicochemical processes during catalysis to optimize their use and to further develop better catalysts. However, simulating these dynamic processes is challenging due to the need for a reliable quantum chemical method to describe chemical bond breaking and bond formation during the processes but, at the same time, fast enough to sample a large number of configurations required to compute the corresponding free energy surfaces. Density functional theory (DFT) is often used to explore Pt-NPs; nonetheless, it is usually limited to some minimum-energy reaction pathways on static potential energy surfaces because of its high computational cost. We report here a combination of the density functional tight binding (DFTB) method as a fast but reliable approximation to DFT, the steered molecular dynamics (SMD) technique, and the Jarzynski equality to construct free energy surfaces of the temperature-dependent diffusion and growth of platinum particles on a titania surface. In particular, we present the parametrization for Pt-X (X = Pt, Ti, or O) interactions in the framework of the second-order DFTB method, using a previous parametrization for titania as a basis. The optimized parameter set was used to simulate the surface diffusion of a single platinum atom (Pt1) and the growth of Pt6 from Pt5 and Pt1 on the rutile (110) surface at three different temperatures (T = 400, 600, 800 K). The free energy profile was constructed by using over a hundred SMD trajectories for each process. We found that increasing the temperature has a minimal effect on the formation free energy; nevertheless, it significantly reduces the free energy barrier of Pt atom migration on the TiO2 surface and the transition state (TS) of its deposition. In a concluding remark, the methodology opens the pathway to quantum chemical free energy simulations of Pt-NPs' temperature-dependent growth and other transformation processes on the titania support.

A comparative study of the effectiveness of multiagent platinum based concurrent plus adjuvant versus conventional single agent platinum based concurrent chemotherapy in carcinoma cervix.

85 Background: Cervical cancer is the 4th most common cancer in females worldwide. Combination of external beam radiotherapy (EBRT) and intracavitary brachytherapy (BT) with concurrent chemotherapy is the current standard of care for locally advanced cervical cancer. Even though the trials used separate combinations, the common end point suggested that platinum is single most effective chemotherapy agent. Since the latest data on platinum based polychemotherapy globally indicates its overall benefit, further trials are required to determine what regimens would be ideal for treatment of cervical cancer with maximum benefits and least toxicities. Objectives: 1. To compare the response to doublet polychemotherapy with conventional chemotherapy in carcinoma cervix treated with chemoradiation. 2. To compare toxicity profile of doublet polychemotherapy with conventional chemotherapy. Methods: 66 patients of carcinoma cervix were enrolled in this study and were randomized to two arms. Arm A (n=34) was the experimental arm and the patients received concurrent weekly cycles of cisplatin(40mg/m2) plus gemcitabine (125mg/m2) along with EBRT followed by HDR brachytherapy, after 2-3 weeks of which they received 2 adjuvant cycles (21 days each) of gemcitabine (1000mg/m2 on Day1 and Day 8) and cisplatin (50mg/m2 on Day 1). Arm B(n=32) was the control arm and the patients received standard treatment which is concurrent weekly cycles single agent cisplatin(40mg/m2) with EBRT followed by HDR brachytherapy. EBRT doses ranged from 45Gy to 50.4 Gy at 1.8 to 2 Gy per fraction .BT application was either ICBT or ISBT depending on tumour response to EBRT, assessed by MRI. Patients were followed up for response assessment and late toxicities within 6 months of completion of treatment by clinical examination and MRI which was reported using RECIST 1.1 criteria. Results: On 6 month follow up MRI, number of patients achieving CR was 10% higher in the experimental arm (Arm A, n=33;97.06%) than the control arm (Arm B, n=28;87.5%).PR was seen in 2 patients, both from Arm B. Of the 3 patients presenting with PD at follow up 1 belonged to Arm A and 2 to Arm B (2.94% vs 6.25%). On pre-brachytherapy MRIs, the size reduction was better in Arm A and this reduction allowed a majority of patients in said arm to undergo ICBT instead of ISBT. The number of patients achieving >50% reduction post EBRT was 40% higher in Arm A. Acute GI and Hematological toxicities were seen in both arms but were higher in Arm A. as was Grade 3 neutropenia. Late toxicities were similar in both arms. Conclusions: The study concluded that the use of multiagent platinum-based chemotherapy in concurrent plus adjuvant setting can be advantageous. Improved tumour reduction can be achieved & disease can be made more amenable for ICBT. The accompanying toxicities were transient and clinically manageable.

A Platinum Nanowire Sensor for Ethylene in Air.

A single platinum nanowire (PtNW) chemiresistive sensor for ethylene gas is reported. In this application, the PtNW performs three functions: (1) Joule self-heating to a specified temperature, (2) in situ resistance-based temperature measurement, and (3) detection of ethylene in air as a resistance change. Ethylene gas in air is detected as a reduction in nanowire resistance by up to 4.5% for concentrations ranging from 1 to 30 ppm in an optimum NW temperature range from 630 to 660 K. This response is rapid (30-100 s), reversible, and reproducible for repetitive ethylene pulses. A threefold increase in signal amplitude is observed as the NW thickness is reduced from 60 to 20 nm, commensurate with a signal transduction mechanism involving surface electron scattering.

Single Pt atom-based gas sensor: Break the detection limit and selectivity of acetone

To improve gas sensing performance of oxide semiconductor is a collective goal of science community, due to that gas sensor is a class of pivotal component of environmental monitoring, the Internet of things and medical equipment. We introduced isolated single platinum atoms on the defective WO3−x nanosheets (SA-Pt/WO3−x), and investigated the status of single atoms by XPS, HAADF-STEM and in situ FT-IR and so forth. The SA-Pt/WO3−x based sensor exhibits high response level (Ra/Rg=43.4 to 5 ppm), exceptional ultrahigh selectivity (Sbest/Ssecond=2.8) and ultimate detection limit (Ra/Rg=4.3 to 0.1 ppm) in acetone gas sensing. In addition, the counterparts of WO3 and Pt nanoparticles were utilized as comparison to investigate the synthesis and gas sensing mechanism thoroughly. This work illustrates the research to fit the needs of ultralow concentration gas sensor application.

Engineering single Pt Atoms on hybrid amorphous/crystalline CoFe layered double hydroxide accelerates the charge transfer for solar water splitting

Owing to the sluggish kinetics suppressing the oxygen evolution reaction, developing single atoms (SAs) catalyst oxygen evolution reaction catalysts on photoelectrodes is challenging for accelerating charge separation and transfer on photoelectrochemical water splitting. Herein, we elaborately demonstrate the decoration of platinum SAs on hybrid crystalline/amorphous CoFe LDH, and assess the role of SAs on the photogenerated charge carrier separation and transport of photoelectrode. The crystalline/amorphous CoFe LDH is capable of embedding the platinum SAs in its structure by modulating the electronic structure. The single atoms platinum in catalyst enables the effective charge transfer and suppress the charge recombination of the BiVO4 photoelectrode. The SAs Pt/AC-CoFe catalyst delivers an overpotential of 230 mV at 10 mA cm−2, obviously lower than those of AC-CoFe without the introduction of SAs Pt. The SAs Pt/AC-CoFe/BiVO4 exhibits an excellent PEC performance, a current density of 5.14 mA cm−1 obtained at 1.23 VRHE in 1 M KBi under one sun illumination with a stability of 20 h. This work proposes a rational design of single atoms catalysts decorated on semiconductors and reveals the potential of the single atoms to boost charge carrier kinetics.

Visualizing Atomic Quantum Defects in Ultrathin 1T-PtTe2.

Defects are of significant importance to determine and improve the distinct properties of 2D materials, such as electronic, optical, and catalytic performance. In this report, we observe four types of point defects in atomically thin flakes of 1T-PtTe2 by using low-temperature scanning tunnelling microscopy and spectroscopy (STM/S). Through the combination of STM imaging and simulations, such defects are identified as a single tellurium vacancy from each side of the top PtTe2 layer and a single platinum vacancy from the topmost and next layer. The density functional theory (DFT) calculations reveal that the platinum vacancies from both the monolayer and bilayer exhibit a local magnetic moment. In bilayer PtTe2, the interlayer coulomb screening effect reduces the local magnetic momentum of the single platinum vacancy. Our research provides meaningful guidance for further experiments about the effects of intrinsic defects on potential functions of thin 1T-PtTe2, such as catalysis and spintronic applications.