Tool For Tuning Research Articles

Modulating the large vacancy types of CuS ultrathin nanosheets via defect engineering to improve the photocatalytic antibacterial performance

Defect engineering is emerging as an important tool for tuning the photocatalytic antibacterial properties of nanomaterials. However, its development is constrained by the lack of exploration of defect engineering for large defect types. We designed CuS and CuS-200 ultrathin nanosheets with different large vacancy types VCuSSCuCu and VCuSSCuCuCu, respectively. The antibacterial test results demonstrated that CuS-200 ultrathin nanosheets exhibited stronger bactericidal effect on Escherichia coli (E. coli) than CuS under near-infrared (NIR) light. The high antibacterial efficiency was attributed to the improved energy band structure, which helped CuS-200 absorb light and improved photothermal conversion efficiency. In addition, the optimized electronic structure and the strong oxygen adsorption ability drove CuS-200 to produce a large amount of reactive oxygen species (ROS). This work provided new ideas for the preparation of efficient bactericides and new strategies for the design and preparation of catalysts with specific photocatalytic properties.

Facile growth of perovskite nanoparticles confined on dimension-controlled Si nanorod arrays for various promising photophysical applications

In this study, a facile growth of hybrid perovskite nanoparticles (NPs) has been demonstrated on mesoporous, high-aspect ratio, morphology-controlled Si nanorod (NR) arrays. A generic method of directly confining perovskite nanocrystallites (average size <7 nm) on a mesoporous substrate without the use of colloidal stabilization was introduced. The perovskite NPs coated on dimension-and position-controlled Si NR arrays were systematically investigated by their various photophysical properties such as optical reflectance, cathodoluminescence (CL), and photoluminescence (PL) behaviors at both room temperature and low temperature. The dimension and position of the Si NR arrays were controlled by e-beam lithography followed by selective metal-assisted chemical etching (MACE). Organic-inorganic perovskite NPs were synthesized on the surface of Si NR array by spin coating of perovskite precursor solution and followed by annealing. The porous and rough sites on the surface of the NR arrays acted as nucleation centers for the formation of perovskite NPs. Due to the excitonic recombination of CH3NH3PbBr3, the NPs confined on the various NR templates exhibited strong PL emission in the 505–510 nm region. Furthermore, due to greater radiative recombination and lesser carrier trapping in the NPs, the PL and CL emission intensities of the perovskite NPs localized on the surface of the NR array were dramatically increased (PL enhancement factor ∼ 7.7, when NR aspect ratio ∼ 17.2) as compared to the bulk perovskite microcrystals. The low-temperature PL study revealed higher exciton binding energy of the NPs as compared to the bulk microcrystalline film. A systematic investigation revealed that the optical absorption, as well as the emission color of the perovskite NPs, can be tuned by the aspect ratio of the Si NR arrays. The results of our studies indicate the application of bandgap engineering of perovskite nanocrystals through confinement in a mesoporous, well-organized, regularly-ordered template as a powerful tool for tuning the emission wavelength in next-generation photonic sources. Furthermore, the important findings on the periodic array of photoactive nanoscale materials introduced in this manuscript may open up huge opportunities in numerous cutting-edge applications such as light emitting diode arrays, photodetector arrays, individually addressable devices, display devices with controlled pixel size and pixel density, etc.

Nasschemische Bottom‐up Synthese von Graphen‐Nanostreifen mit atompräzisen Nanoporen

AbstractDie Inkorporation von Nanoporen in Graphen‐Nanostrukturen wurde als effiziente Methode zur Anpassung der Bandlücke und elektronischen Struktur dieser Materialien demonstriert. Allerdings ist die atomgenaue Einbettung uniformer Nanoporen in Graphen‐Nanostreifen (GNS, engl. GNR) auf atomarer Ebene durch Mangel an effizienten Synthesestrategien bislang unterentwickelt. Wir berichten hier vom ersten lösungschemisch dargestellten, vollständig durch Scholl‐Reaktion konjugierten porösen GNS (pGNS), welchen wir durch das atomgenau dargestellte Polyphenylen P1 mit vorinstallierten hexagonalen Makrozyklen zugänglich machen konnten. pGNS enthält periodische Poren im sub‐Nanometerbereich (0.6 nm) mit einem Abstand von 1.7 nm zueinander. Um unsere Synthesestrategie zu untermauern, wurden zwei poröse Modellverbindungen (1 a, 1 b) mit einer zu pGNS identischen Pore erfolgreich dargestellt. Die chemische Struktur und photophysikalischen Eigenschaften von pGNS wurden durch verschiedene spektroskopische Methoden untersucht. Die eingebetteten periodischen Nanoporen vermindern die π‐Konjugation und damit die Interaktion zwischen den Nanostreifen, verglichen mit nicht porösen GNS von ähnlicher Breite. pGNS zeigt demzufolge eine erhöhte Bandlücke und eine verbesserte nasschemische Prozessierbarkeit.

Bottom-up Solution Synthesis of Graphene Nanoribbons with Precisely Engineered Nanopores.

The incorporation of nanopores into graphene nanostructures has been demonstrated as an efficient tool in tuning their band gaps and electronic structures. However, precisely embedding the uniform nanopores into graphene nanoribbons (GNRs) at the atomic level remains underdeveloped especially for in-solution synthesis due to the lack of efficient synthetic strategies. Herein we report the first case of solution-synthesized porous GNR (pGNR) with a fully conjugated backbone via the efficient Scholl reaction of tailor-made polyphenylene precursor (P1) bearing pre-installed hexagonal nanopores. The resultant pGNR features periodic subnanometer pores with a uniform diameter of 0.6 nm and an adjacent-pores-distance of 1.7 nm. To solidify our design strategy, two porous model compounds (1 a, 1 b) containing the same pore size as the shortcuts of pGNR, are successfully synthesized. The chemical structure and photophysical properties of pGNR are investigated by various spectroscopic analyses. Notably, the embedded periodic nanopores largely reduce the π-conjugation degree and alleviate the inter-ribbon π-π interactions, compared to the nonporous GNRs with similar widths, affording pGNR with a notably enlarged band gap and enhanced liquid-phase processability.

Electromagnetic interference shielding performance of Ag/multi-walled carbon nanotubes-poly(methyl methacrylate) composites

An efficient strategy for synthesizing Ag/multi-walled carbon nanotubes-poly(methyl methacrylate) (Ag/MWCNT-PMMA) composites has been proposed. The synthesis concept is based on the modification of oxidized MWCNT with Ag nanoparticles and subsequent distribution of the obtained Ag/MWCNT-Ox hybrids in a PMMA matrix. Herein, Ag/MWCNT-Ox hybrids with various size and content of Ag nanoparticles serve as a tool for tuning the electrical conductivity of the two series of Ag/MWCNT-PMMA composites with MWCNT-Ox content before (4 wt%) and after (10 wt%) the percolation threshold. Adding 0.2 wt% of Ag to the first composite series with nanotubes content of 4 wt% leads to a decrease in the percolation threshold in a three-component system. In the case of the second composite series, the introduction of Ag up to 1 wt% leads to a monotonic increase in the conductivity within one order of magnitude. Ag/MWCNT-PMMA demonstrates high shielding efficiency for incident radiation in the frequency range of 26–37 GHz, most of which is absorbed due to the conductive nature of the material. The improved electromagnetic properties of the Ag/MWCNT-PMMA composites are explained by the uniform distribution of fillers in the polymer, which ensures the formation of a 3D conducting network inside the composite, and by the synergistic interaction between MWCNT and Ag. Thus, Ag/MWCNT-PMMA composites have broad application prospects in the field of electromagnetic compatibility.

Multivariate Flexible Framework with High Usable Hydrogen Capacity in a Reduced Pressure Swing Process

Step-shaped adsorption-desorption of gaseous payloads by flexible metal-organic frameworks can facilitate the delivery of large usable capacities with significantly reduced energetic penalties. This is desirable for the storage, transport, and delivery of H2, as prototypical adsorbents require large swings in pressure and temperature to achieve usable capacities approaching their total capacities. However, the weak physisorption of H2 typically necessitates undesirably high pressures to induce the framework phase change. As de novo design of flexible frameworks is exceedingly challenging, the ability to intuitively adapt known frameworks is required. We demonstrate that the multivariate linker approach is a powerful tool for tuning the phase change behavior of flexible frameworks. In this work, 2-methyl-5,6-difluorobenzimidazolate was solvothermally incorporated into the known framework CdIF-13 (sod-Cd(benzimidazolate)2), resulting in the multivariate framework sod-Cd(benzimidazolate)1.87(2-methyl-5,6-difluorobenzimidazolate)0.13 (ratio = 14:1), which exhibited a considerably reduced stepped adsorption threshold pressure while maintaining the desirable adsorption-desorption profile and capacity of CdIF-13. At 77 K, the multivariate framework exhibits stepped H2 adsorption with saturation below 50 bar and minimal desorption hysteresis at 5 bar. At 87 K, saturation of step-shaped adsorption occurs by 90 bar, with hysteresis closing at 30 bar. These adsorption-desorption profiles enable usable capacities in a mild pressure swing process above 1 mass %, representing 85-92% of the total capacities. This work demonstrates that the desirable performance of flexible frameworks can be readily adapted through the multivariate approach to enable efficient storage and delivery of weakly physisorbing species.

Crystallite Tuning of Magnetic Properties in S = 1/2 Ni(III) Cyclam (Bi)sulfate Complex Salts

Molecular-level crystallographic tuning of a coordination complex structure can enable manipulation of the small energies that govern intra- and intermolecular responses toward molecular actuators. Chemically tuning of the magnetic response of S = 1/2 coordination complexes is of particular interest in recent years because these species represent the simplest electron-based quantum bits (qubits) for developing molecular quantum computers. In this report, we discuss the crystallographic tuning tools and corresponding magnetic properties of novel S = 1/2 Ni(III) cyclam complex salts: strong antiferromagnetic coupling in sulfate-bridged chain {[Ni(cyclam)(μ2-SO4)]ClO4·H2O}n (1) and field-, temperature-, and size-dependent slow magnetic relaxation in molecular [Ni(cyclam)(HSO4)2]HSO4 (2). We have reported two methods of manipulating the dynamic magnetic response of these coordination molecules: particle size selection and deuteration. We find that particle size dependency, which we attribute to the phonon bottleneck effect, for the magnetic dynamics in the parent compound 2, is removed in deuterated 2-d7, revealing only the faster molecular relaxation mode(s).

Graphene Oxide-Grafted Hybrid Diblock Copolymer Brush (GO-graft-PEG6k-block-P(MA-POSS)) as Nanofillers for Enhanced Lithium Ion Conductivity of PEO-Based Nanocomposite Solid Polymer Electrolytes.

Nanocomposite solid polymer electrolytes (NSPEs) with PEO as the matrix and (i) GO or (ii) GO-graft-PEG6k or (iii) GO-graft-PEG6k-block-P(MA-POSS) as nanofillers have been fabricated to elucidate the impact of the filler morphology on the lithium ion conductivity. GO-graft-PEG6k was obtained by grafting PEG6k onto GO via esterification. GO-graft-PEG6k-block-P(MA-POSS) was prepared via surface-initiated atom transfer radical polymerization. Fourier-transform infrared spectroscopy revealed enhanced salt dissociation and complexation between the filler and PEO host that could be attributed to Lewis acid-base interactions. Electrochemical impedance spectroscopy revealed the improved ion conductivity of the fabricated NSPEs as compared with the pristine PEO-LiClO4. As an example, at 50 °C, the ion conductivity increased to 4.01 × 10-5 and 6.31 × 10-5 S cm-1 with 0.3% GO and 0.3% GO-graft-PEG6k, respectively, from 2.36 × 10-5 S cm-1 of PEO-LiClO4, suggesting that the filler with brush-like architecture (GO-graft-PEG6k) is more efficient in enhancing the ion conductivity. Further increase in filler content resulted in lowering of the ion conductivity that could be ascribed to aggregation of the filler. The most dramatic impact on conductivity was observed with the incorporation of brush-like GO-graft-PEG6k-block-P(MA-POSS) as a nanofiller (3.0 × 10-4 S cm-1 at 50 °C with 1.0 wt % filler content). The increase in ion conductivity in the current systems, as opposed to the conventional view, could not be correlated with the content of the amorphous phase of the matrix. The conduction mechanism is still unclear; nevertheless, it could be assumed that in addition to the ion conduction through the PEO matrix, the filler forms additional low-energy ion conducting channels at its interface with the matrix. The pendent POSS nanocages of GO-graft-PEG6k-block-P(MAPOSS) might probably increase the free volume at the interface with the matrix that is associated with higher chain and ion mobility, thus further enhancing the ion conductivity as compared with GO and GO-graft-PEG6k. The faster ion dynamics in 1.0 wt % GO-graft-PEG6k-block-P(MAPOSS) NSPEs has also been verified by the dielectric relaxation studies. Thus, integration of both the PEG and POSS nanocages into GO-grafted brush-like architecture offers a new tool for tuning the lithium ion conductivity for potential Li ion battery applications.

Recovering Corrupted Data in Wind Farm Measurements: A Matrix Completion Approach

Availability of reliable and extended datasets of recorded power output from renewables is nowadays seen as one of the key drivers to improve the design and control of smart energy systems. In particular, these datasets are needed to train artificial intelligence methods. Very often, however, datasets can be corrupted due to lack of records connected to failures of the acquisition system, maintenance downtime periods, etc. Several recovery (imputation) methods have been used to guess and replace missing data. In this paper, we exploit the matrix completion approach. The available measures of several variables referring to a real onshore wind farm are organized into a matrix in a daily range and the Singular Value Thresholding method is used to carry out the matrix completion process. Numerical results show that matrix completion is a reliable and parameter-free tuning tool to impute missing data in these applications.

ExpressInHost: A Codon Tuning Tool for the Expression of Recombinant Proteins in Host Microorganisms

ExpressInHost (<a href="https://gitlab.com/a.raguin/expressinhost" target="_blank">https://gitlab.com/a.raguin/expressinhost</a>) is a GTK/C++ based user friendly graphical interface that allows tuning the codon sequence of an mRNA for recombinant protein expression in a host microorganism. Heterologous gene expression is widely implemented in biotechnology companies and academic research laboratories. However, expression of recombinant proteins can be challenging. On the one hand, maximising translation speed is important, especially in scalable production processes relevant to biotechnology companies, but on the other hand, solubility problems often arise as a consequence, since translation ‘pauses’ might be key to allow the nascent polypeptide chain to fold appropriately. To address this challenge, we have developed a software that offers three distinct modes to tune codon sequences using the genetic code redundancy. The tuning strategies implemented take into account the specific tRNA resources of the host and that of the native organism. They balance rapid translation and native speed mimicking, which might be important to allow proper protein folding, thereby avoiding protein solubility problems.

Effects of the medium fractionality and oscillating potential profiles on the Superarrivals of the Gaussian wave packets

So far, the less studied superarrival concept is only investigated in the standard integer-order Schrodinger equation formalism. In this research, we assume a fractional Schrodinger equation. Also, in the available papers on the superarrival phenomenon, a monotonic increasing or decreasing potential profile is considered, while here, an oscillating potential profile is supposed. A Gaussian wave packet impinging on an oscillating potential profile has been explored. It is shown that the wave packet velocity changes according to relation α/2 kα-1 = v, assuming ћ = 1and m = 1. The wave packet traveling speed slows down using the fractionality order α. Also, we have demonstrated that the fractionality order α can be used as a tuning tool to obtain atypical early arrival magnitude η. Finally, we propose that the superarrival concept can be experimentally tested by impinging a Gaussian wave packet on an oscillating potential profile that can be realized in the tautomerization and isomerization reactions.

DNA Oligonucleotides as Antivirals and Vaccine Constituents against SARS Coronaviruses: A Prospective Tool for Immune System Tuning.

The SARS-CoV-2 pandemic has demonstrated the need to create highly effective antivirals and vaccines against various RNA viruses, including SARS coronaviruses. This paper provides a short review of innovative strategies in the development of antivirals and vaccines against SARS coronaviruses, with a focus on antisense antivirals, oligonucleotide adjuvants in vaccines, and oligonucleotide vaccines. Well-developed viral genomic databases create new opportunities for the development of innovative vaccines and antivirals using a post-genomic platform. The most effective vaccines against SARS coronaviruses are those able to form highly effective memory cells for both humoral and cellular immunity. The most effective antivirals need to efficiently stop viral replication without side effects. Oligonucleotide antivirals and vaccines can resist the rapidly changing genomic sequences of SARS coronaviruses using conserved regions of their genomes to generate a long-term immune response. Oligonucleotides have been used as excellent adjuvants for decades, and increasing data show that oligonucleotides could serve as antisense antivirals and antigens in vaccine formulations, becoming a prospective tool for immune system tuning.

Modeling size and edge functionalization of MXene-based quantum dots and their effect on electronic and magnetic properties.

In the last six years, the synthesis of MXene-based quantum dots (MXQDs) has gained widespread attention. Due to the quantum confinement effect, it is possible to significantly improve their properties compared to 2D counterparts, such as higher chemical stability and better electronic and optical properties. However, despite the growing interest in their properties, much remains unexplored. One of the biggest challenges is to study in more detail the structure of quantum dots, in particular, their edge functionalization and its effect on their properties. In this paper, the structural stability and electronic and magnetic properties of Ti2CO2 QDs based on different lateral dimensions and edge functionalization (-O, -F, and -OH) are investigated using density functional theory. The study shows that the energy gap of Ti2CO2-O QDs decreases with increasing lateral size for both nonmagnetic (spin-unpolarized, close shell) and magnetic (spin-polarized, open shell) cases. Furthermore, the magnetic behavior of quantum dots was revealed by shrinking from 2D Ti2CO2 to 0D Ti2CO2 QDs with lateral dimensions below 1.4 nm. The binding energy confirms the stability of all three types of edge functionalization, while the most stable structure was observed under fully saturated edge oxygenation. Moreover, it was also found that the spin density distribution and the energy gap of Ti2CO2-X QDs (X = O, F, and OH) are both dependent on the type of atom saturation. Size and edge confinement modeling has been demonstrated to be an effective tool for tuning the electronic and magnetic properties of MXQDs. Moreover, the observed enhanced spin polarization together with tunable magnetic properties makes the ultrafine Ti2CO2-X QDs promising candidates for spintronic applications.

Tuning catalysis by surface-deposition of elements on oxidation catalystsviaatomic layer deposition

This study on surface-modifications of bulk oxidation catalysts with sub-monolayers of POx, BOxand MnOxviaatomic layer deposition demonstrates this method to be a powerful tool for tuning the performance in selective oxidations of light alkanes.

CharmSeeker: Automated Pipeline Configuration for Serverless Video Processing

Video processing plays an essential role in a wide range of cloud-based applications. It typically involves multiple pipelined stages, which well fits the latest fine-grained serverless computing paradigm if properly configured to match the cost and delay constraints of video. Existing configuration tools, however, are primarily developed for traditional virtual machine clusters with general workloads. This paper presents CharmSeeker, an automated configuration tuning tool for serverless video processing pipelines. We first carefully examine the key steps and the performance bottlenecks for video processing over modern serverless platforms. Then, we identify the configuration space for processing pipelines and leverage a carefully designed Sequential Bayesian Optimization search scheme to identify promising configurations. We further address the practical challenges toward integrating our solution into real-world systems and develop a prototype with AWS Lambda. Evaluation results show that CharmSeeker can find out the optimal or near-optimal configurations that improve the relative processing time up to 408.77%. It is also more robust and scalable to various video processing pipelines compared with state-of-the-art solutions.

Parameters tuning of multi-model database based on deep reinforcement learning

As we all know, the performance of database management system is directly linked to a vast array of knobs, which control various aspects of system operation, ranging from memory and thread counts settings to I/O optimization. Improper settings of configuration parameters are shown to have detrimental effects on performance, reliability and availability of the overall database management system. This is also true for multi-model databases, which use a single platform to support multiple data models. Existing approaches for automatic DBMS knobs tuning are not directly applicable to multi-model databases due to the diversity of multi-model database instances and workloads. Firstly, in cloud environment, they have difficulty adapting to changing environments and diverse workloads. Secondly, they rely on large-scale high-quality training samples that are difficult to obtain. Finally, they focus primarily on throughput metrics, ignoring tuning requirements for resource utilization. Therefore, in this paper, we propose a multi-model database configuration parameters tuning solution named MMDTune. It selects influential parameters, recommends the optimal configurations in a high-dimensional continuous space. For different workloads, the TD3 algorithm is improved to generate reasonable parameter adjustment plans according to the internal state of the multi-model databases. We conduct extensive experiments under 5 different workloads on real cloud databases to evaluate MMDTune. Experimental results show that MMDTune adapts well to a new hardware environment or workloads, and significantly outperforms the representative tuning tools, such as OtterTune, CDBTune.

Controlled dislocation density as enhancer of the magnetic response in multiferroic oxide nanoparticles

We report on the application of cryomilling for the synthesis of oxide ceramics nanoparticles with controlled dislocation densities using the rhombohedral BiFeO3 compound as a model system. Multiferroic BiFeO3 nanoparticles were prepared with controlled crystallite size, micro-strain and dislocation density. After milling for 150 min the average crystallite size is reduced to 23 nm, the levels of micro-strain increased to 1.2 % and the dislocation density reaches 1.7×1013cm−2. This shows that the cryomilling promotes the nanostructuration of the samples and the introduction of atomic defects such as dislocations. In addition we found an enhancement of the magnetic properties resulting from a combination of the presence of small nanoparticles and uncompensated spins along the dislocation lines. The isothermal magnetization measurements showed a weak-ferromagnetic behavior with 0.58 emu/g at 15 kOe at room temperature. Mössbauer spectroscopy ruled out the formation of Fe2+ ions and also revealed the presence of a superparamagnetic contribution. The control of crystallite size along with dislocation density in BiFeO3 is proposed as a powerful tool for tuning its magnetic properties.

Models of Reproductive Behavior in an Urban Family: Generational Conflict of Values

Based on the materials of a sociological study conducted in March – October 2021, the main reasons for changes in reproductive attitudes in urban families are considered, models of reproductive behavior are analyzed: "deferred parenthood", "responsible parenthood", Childfree, which are shared by the majority of modern youth. The source of empirical data was an online survey of students. The sample consisted of 2,439 students. In addition, a telephone survey was conducted, which was attended by 600 representatives of urban families of different ages in Yekaterinburg. The reproductive attitudes of young citizens have been revealed, which conflict with the traditional ideas of older generations about the preferred age of marriage and the birth of the first child. Our research suggests that the reproductive attitudes and behavior of young people are transformed from a value-rational model to a goal-oriented one. Purposeful reproductive behavior is a phenomenon of modern life strategies of young people. Such behavior presupposes the freedom of individual reproductive choice: a conscious decision to have children or refuse to procreate. At the same time, the younger generation does not reject the scenarios of matrimonial behavior and the birth of children of older generations, supports "pro-family" values. The authors believe that it makes sense to study this value conflict and take it into account as a "subtle tuning tool" in shaping the policy of stimulating fertility.

Fast and optimal tuning of fractional order PID controller for AVR system based on memorizable-smoothed functional algorithm

Voltage regulation in automatic voltage regulator (AVR) system has been one of the most challenging engineering problem due to the uncertain load condition. Therefore, the control of AVR system by using PID based controller is one of the essential approach to maintain the performance of the AVR system. Subsequently, the application of FOPID controller in AVR system is gaining more attention recently. This is because the FOPID has additional control parameters at the derivative and integral parts than the PID controller, which has the advantage to improve the output response of AVR system while retaining the robustness and simple construction as the PID controller. Nevertheless, many existing optimization tools for tuning the FOPID controller, which are based on multi-agent based optimization, require large number of function evaluation in their algorithm that could lead to high computational burden. Therefore, this study proposes a modified smoothed function algorithm (MSFA) based method to tune the FOPID controller of AVR system since it requires fewer number of function evaluation per iteration. Moreover, the proposed MSFA based method also can solve the unstable convergence issue in the original smoothed function algorithm (SFA), thus able to provide better convergence accuracy. The simulations of step response analysis, Bode plot analysis, trajectory tracking analysis, disturbance rejection analysis, and parameter variation analysis are conducted to evaluate the effectiveness of the proposed MSFA-FOPID controller of AVR system. Consequently, the results obtained from the simulations revealed that the proposed method is highly effective and significantly improved as compared to the other existing FOPID controllers.

Coordination-Delayed-Hydrolysis Method for the Synthesis and Structural Modulation of Titanium-Oxo Clusters.

ConspectusAtomically precise titanium-oxo clusters (TOCs) are the structure and reactivity model compounds of technically important TiO2 materials, which could help build structure-property relationships and achieve property modulation at the molecular level. However, the traditional formation of TOCs has relied on the poorly controllable hydrolysis of titanium alkoxide in the solvent for a long time, limiting the development of TOC structural chemistry to a great extent. In addition, easily hydrolyzable alkoxy groups would be still coordinated on the surface of the TOCs generated by this method, making the clusters sensitive and unstable to the moisture. To achieve controllable preparation of TOCs, we believe it is crucial to attenuate the hydrolysis of titanium ions in the formation process of a cluster. To this end, we have recently applied an effective coordination-delayed-hydrolysis (CDH) strategy for TOC synthesis, which provides powerful tools for tuning their structures.In this Account, at the beginning, a brief introduction to the coordination-delayed-hydrolysis strategy is supplied, and its predominant features for constructing novel TOCs are highlighted. In subsequent sections, we discuss how the applied chelating organic/inorganic ligands (named hydrolysis delayed ligands) influence the hydrolysis process of Ti4+ ions to form a large family of TOCs with various nuclearities and core structures. Various hydrolysis delayed ligands have been explored, ranging from common O-donor ligands (carboxylate, phenol, or sulfate) to rarely used N-donor ligands (pyrazole) or bifunctional O/N-donor ones (quinoline, oxime, or alkanolamine). Breakthroughs in the symmetry, configuration, and cluster nuclei of TOCs have been accordingly achieved. Then, we show that this CDH method can be used to tune the surface structure of TOCs by modifying functional organic ligands. As a result, the physicochemical properties of TOCs, especially optical band gaps, can be optimized, and their stability under ambient conditions is significantly improved. In addition, we illustrate that the reversible bonds between hydrolysis delayed ligands and Ti ions further allows us to introduce active heterometal ions or clusters upon or inside the Ti-O cores to prepare heterometallic TOCs with unprecedented structures and properties. In particular, noble metal (Ag ions or clusters) has been incorporated into Ti-O clusters for the first time. As a summary, the coordination-delayed-hydrolysis strategy has realized the controllable hydrolysis of Ti4+ ions to some extent, breaking through the limitations of traditional synthesis methods and producing fruitful results in the field of titanium-oxo clusters. It is believed that this CDH method would also be effective for synthesizing oxo clusters of other easily hydrolyzed metal ions (Al3+, Sn4+, In3+, etc.) to afford significant contribution for the cluster community.