Search NASA⌕ Search

SEARCH · Search NASA

Results for “Morphology control”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Efficient Control of Atom Arrangement in Ternary Metal Chalcogenide Nanoparticles Using Precursor Oxidation State

Controlling both the concentration and the distribution of elements in a given material is often crucial to extracting and optimizing synergistic properties of the various constituents. An interesting class of such multielement materials is metal chalcogenide nanoparticles, which exhibit a wide range of composition-dependent optoelectronic properties including both bandgap-mediated processes and localized surface plasmon resonance properties, each of which is useful in applications ranging from energy conversion to sensing. Because metal chalcogenide nanoparticles can support several different metal elements in a variety of chalcogen lattices, this material class has particularly benefited from the ability to control both atom concentration and atom arrangement to tailor final particle properties. The primary method to access complex, multimetallic chalcogenide particles is via a postsynthetic cation exchange strategy. One-pot syntheses have been less explored to access these complex particles, although this route is desirable for economy and scalability. In this work, we compare the composition and morphology outcomes from cation exchange and one-pot preparation approaches using a Cu/Ag/Se system, which is already known to exhibit both binary and ternary metal chalcogenide phases. We show that at similar concentrations of the two metal cations, initial reaction conditions for the one-pot method yield multicomponent nanoparticles, whereas cation exchange yields homogeneous ternary metal chalcogenide structures. We then show that by tuning the precursor oxidation state for the one-pot method, this approach can be used to access homogeneous ternary metal chalcogenide particles that are similar in atom arrangement to the particles obtained using cation exchange. Taken together, our results demonstrate reliable synthetic methods that yield a variety of controlled compositions and composition morphologies in the Cu/Ag/Se system. Importantly, we demonstrate that this entire collection of architectures can all be accessed via a one-pot method simply by modifying metal precursor chemistry. The mechanistic insights gained and the resulting streamlined syntheses outlined indicate pathways to easily scaled, highly tailorable syntheses for rapid translation into downstream technologies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Magnetic and Optical Properties of Au–Co Solid Solution and Phase-Separated Thin Films and Nanoparticles

The chemical composition and morphology of Au x Co 1–x thin films and nanoparticles are controlled via a combination of cosputtering, pulsed laser-induced dewetting (PLiD), and annealing, leading to tunable magnetic and optical properties. Regardless of chemical composition, the as-deposited thin films and as-PLiD nanoparticles are found to possess a face-centered cubic (FCC) Au x Co 1–x solid-solution crystal structure. Annealing results in large phase-separated grains of Au and Co in both the thin films and nanostructures for all chemical compositions. The magnetic and optical properties are characterized via vibrating sample magnetometry (VSM), ellipsometry, optical transmission spectroscopy, and electron energy loss spectroscopy (EELS). Despite the exceptionally high magnetic anisotropy inherent to Co, the presence of sufficient Au (72 atom %) in the Au x Co 1–x solid solution results in superparamagnetic thin films. Among the as-PLiD nanoparticle samples, an increased Co composition leads to a departure from traditional ferromagnetism in favor of wasp-waisted hysteresis caused by magnetic vortices. Phase separation resulting from annealing leads to ferromagnetism for all compositions in both the thin films and nanoparticles. The optical properties of Au x Co 1–x nanostructures are also largely influenced by the chemical morphology, where the Au x Co 1–x intermixed solid solution has significantly damped plasmonic performance relative to pure Au and comparable to pure Co. Phase separation greatly enhances the quality factor, optical absorption, and electron energy loss spectroscopy (EELS) signatures. The enhancement of the localized surface plasmon resonances (LSPRs) scales with the reduction in Co composition, despite EELS evidence that excitation of the Co portions of a nanoparticle can provide a similar, and in some instances enhanced, LSPR resonance compared to Au. This behavior, however, is seemingly limited to the LSPR dipole mode, while higher-order modes are greatly damped by a Co aloof position. As a result, this observed magneto-plasmonic functionality and tunability could be applicable in biomedicine, namely, cancer therapeutics.

annealing (metallurgy)↗
DOE OSTI2020

Colloidal Three-Dimensional Covalent Organic Frameworks and Their Application as Porous Liquids

Developing solid porous materials into free-flowing liquids with permanent porosity is a promising strategy for overcoming certain limitations of conventional sorbent materials employed in gas storage and separation applications. The ability to control the pore size and chemical functionalities of organic frameworks gives these particular nanoporous materials distinct advantages over other small cage-like molecules or hollow particles that have been developed into porous liquids. Here, we describe the synthesis of a 3D imine-linked colloidal covalent organic framework (COF)-based porous liquid, designed for efficient size-exclusion of solvent, as well as for long-term stability. By tethering ionic liquids to the colloid surface, the colloids can be dried, purified, and resuspended in a variety of solvents without irreversible aggregation typically observed of COF colloids. Colloid size could be controlled between 50 and 400 nm, with surface areas as high as 800 m2/g. The 3D intertwining morphology of the colloids had pore sizes ranging from 5 to 14 Å, allowing them to efficiently sizeexclude bulky ionic liquids. The COF colloids were stable towards flocculation in an ionic liquid for > 1 year. Permanent porosity was confirmed with a combination of 19F NMR measurements and gas sorption techniques. CO2 and CH4 uptake in these porous liquids increased more than 10 and 20-fold, respectively, over non-porous, neat ionic liquid control samples. The work not only advances the state of COF-based colloid science but also represents a practical advance towards developing more robust, tunable framework-based porous liquid materials for a host of gas storage and separation applications.

Mow, Rachel E.↗
DOE OSTI2020

Homopolymer self-assembly of poly(propylene sulfone) hydrogels via dynamic noncovalent sulfone-sulfone bonding

Natural biomolecules such as peptides and DNA can dynamically self-organize into diverse hierarchical structures. Mimicry of this homopolymer self-assembly using synthetic systems has remained limited but would be advantageous for the design of adaptive bio/nanomaterials. Here, we report both experiments and simulations on the dynamic network self-assembly and subsequent collapse of the synthetic homopolymer poly(propylene sulfone). The assembly is directed by dynamic noncovalent sulfone–sulfone bonds that are susceptible to solvent polarity. The hydration history, specified by the stepwise increase in water ratio within lower polarity water-miscible solvents like dimethylsulfoxide, controls the homopolymer assembly into crystalline frameworks or uniform nanostructured hydrogels of spherical, vesicular, or cylindrical morphologies. These electrostatic hydrogels have a high affinity for a wide range of organic solutes, achieving >95% encapsulation efficiency for hydrophilic small molecules and biologics. This system validates sulfone–sulfone bonding for dynamic self-assembly, presenting a robust platform for controllable gelation, nanofabrication, and molecular encapsulation.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

The interplay between surface facet and reconstruction on isopropanol conversion over SrTiO 3 nanocrystals

Strontium titanate (SrTiO 3 ) is an extensively investigated perovskite for various applications due to its optical, electrical and chemical properties. To gain an in-depth understanding of the active sites involved in heterogeneous catalysis over the broadly used SrTiO 3 (STO), we studied a model reaction, isopropanol conversion, on three differently shape-controlled nanocrystals: cube, truncated cube and dodecahedra. SEM, XRD and XPS confirmed the morphology, phase and composition of STO shapes. Low energy ion scattering (LEIS) revealed the occurrence of surface reconstruction over STO shapes during O 2 pretreatment at different temperatures. Based on the catalytic activities, scanning transmission electron microscopy images and density functional theory calculations, the step sites on STO derived from surface reconstruction were proposed to be the active sites for isopropanol conversion. This was further confirmed by steady state isotopic kinetic analysis (SSITKA) which demonstrated similar intrinsic turnover frequencies (TOFs) for the differently reconstructed STO shapes. It is concluded that the crystal facets impose an indirect effect on the catalysis of STO via controlling the degrees of surface reconstruction: the less stable STO (1 1 0) facet (dodecahedra) leads to more step sites after reconstruction and hence higher overall reaction rate than the more stable (1 0 0) facet (cube). This work highlights the important interplay between the crystal facet and surface reconstruction in controlling the nature and density of active sties and thus catalysis over complex oxides.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Petaloid-shaped ZnO coated carbon felt as a controllable host to construct hierarchical Li composite anode

Prestoring Li metal into the 3D host via thermal infusion strategy has been considered as an effective approach on suppressing Li dendrites growth of Li-metal anode during cycling. However, the fast Li infusing process generally induces uncontrollable and undesirable structures during the formation of composite Li metal anode. It is widely accepted that both physical and chemical interactions between the molten Li and the hosts provide driving forces for Li infusing into the host, but which one plays the dominant role has not been explored clearly. In this work, a 3D carbon felt coated by petaloid zinc oxide (CFZO) is designed as a controllable host for prestoring Li metal via thermal infusion method. It is revealed that the morphology induced physical driving force plays a more important role than the chemical reaction between ZnO and molten Li in the thermal infusion process. The physical driving force originates from the capillarity effect, depending on the roughness of the host according to Wenzel's model. An adjustable Li infusing process can be controlled to fabricate the Li composite electrode with a hierarchical structure (with dense Li-rich layer and porous Li-poor layer). The unique structure of the CFZO-Li not only provides enough spaces for Li deposition, but also disperses local current density to induce a uniform Li deposition behavior, thus Li dendrites can be suppressed effectively. As a result, CFZO-Li anode exhibits promising cycle stability when coupled with both Li-containing (LiNi 0.8 Co 0.15 Al 0.05 O 2 ) and Li-free (sulfur) cathodes.

25 ENERGY STORAGE↗
DOE OSTI2021

Quasi-Two-Dimensional Earth-Abundant Bimetallic Electrocatalysts for Oxygen Evolution Reactions

The extremely large surface area offered by quasi-two-dimensional (2D) nanostructures is a great advantage for catalytic applications. While bimetallic materials have been discovered as a group of promising catalysts for electrochemical water splitting, a facile and reliable synthesis approach toward 2D morphology to fully release its electrochemical catalytic potential is still lacking. In this work, bimetallic Co–Mo–O ultrathin nanosheets were synthesized by ionic layer epitaxy with controlled composition ratio. The Co–Mo–O nanosheets exhibited a quadrangle shape with a uniform thickness of ~2.5 nm. This 2D morphology largely enriched the surface catalytic active site ratio. Particularly, nanosheets with 2:1 Co-to-Mo ratio showed a substantially enhanced OER catalytic activity with a 3 orders of magnitude higher mass activity compared to benchmark IrO 2 and RuO 2 in an alkaline environment. Furthermore, this study introduces a promising possibility for creating high-performance electrocatalysts from 2D bimetallic materials with a high efficiency for material utilization.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

The Interplay Between Ferroelectricity and Electrochemical Reactivity on the Surface of Binary Ferroelectric Al x B 1–x N

Polarization dynamics and domain structure evolution in ferroelectric Al 0.93 B 0.07 N are studied using piezoresponse force microscopy and spectroscopies in ambient and controlled atmosphere environments. The application of negative unipolar and bipolar first-order reverse curve (FORC) waveforms leads to a protrusion-like feature on the Al 0.93 B 0.07 N surface and a reduction of electromechanical response due to electrochemical reactivity. A surface change is also observed on the application of fast alternating current bias. At the same time, the application of positive biases does not lead to surface changes. Comparatively in a controlled glove box atmosphere, stable polarization patterns can be observed, with minuscule changes in surface morphology. This surface morphology change is not isolated to applying biases to free surface, a similar topographical change is also observed at the electrode edges when cycling a capacitor in an ambient environment. The study suggests that surface electrochemical reactivity may have a significant impact on the functionality of this material in the ambient environment. However, even in the controlled atmosphere, the participation of the surface ions in polarization switching phenomena and ionic compensation is possible.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Two-Dimensional Siloxene Nanosheets: Impact of Morphology and Purity on Electrochemistry

Two-dimensional (2D) siloxene (Si 6 O 3 H 6 ) has shown promise as a negative electrode material for Li-ion batteries due to its high gravimetric capacity and superior mechanical properties under (de)lithiation compared to bulk Si. Here, in this work, we prepare purified siloxene nanosheets through the removal of bulk Si contaminants, use ultrasonication to control the lateral size and thickness of the nanosheets, and probe the effects of the resulting morphology and purity on the electrochemistry. The thin siloxene nanosheets formed after 4 h of ultrasonication deliver an average capacity of 810 mA h/g under a 1000 mA/g rate over 200 cycles with a capacity retention of 76%. Interestingly, the purified siloxene shows lower initial capacity but superior capacity retention over extended cycling. The 2D morphology benefit is illustrated where the parent siloxene nanosheet morphology and structure were largely maintained based on operando optoelectrochemistry, in situ Raman, ex situ scanning electron microscopy, and ex situ transmission electron microscopy. Furthermore, the purified siloxene-based electrode free from crystalline Si impurity experiences the least expansion upon (de)lithiation as visualized by cross-section electron microscopy of samples recovered post-cycling.

25 ENERGY STORAGE↗
DOE OSTI2024

Dislocation half-loop control for optimal V-defect density in GaN-based light emitting diodes

V-defects are morphological defects that typically form on threading dislocations during epitaxial growth of $(0001)$-oriented GaN layers. A V-defect is a hexagonal pyramid-shaped depression with six {$10\bar{1}1$}-oriented sidewalls. These semipolar sidewalls have a lower polarization barrier than the polarization barriers present between the polar c-plane quantum wells and quantum barriers and can laterally inject carriers directly into quantum wells in GaN-based light emitting diodes (LEDs). This is especially important, as the high polarization field in c-plane GaN is a significant factor in the high forward voltage of GaN LEDs. The optimal V-defect density for efficient lateral carrier injection in a GaN LED (∼10 9 cm −2 ) is typically an order of magnitude higher than the threading dislocation density of GaN grown on patterned sapphire substrates (∼10 8 cm −2 ). Pure-edge dislocation loops have been known to exist in GaN, and their formation into large V-defects via low-temperature growth with high Si-doping has recently been studied. Here, in this work, we develop a method for pure-edge threading dislocation half-loop formation and density control via disilane flow, growth temperature, and thickness of the half-loop generation layer. We also develop a method of forming the threading dislocation half-loops into V-defects of comparable size to those originating from substrate threading dislocations.

Crystallographic defects↗
DOE OSTI2020

Effects of elastic softening and helium accumulation kinetics on surface morphological evolution of plasma-facing tungsten

Based on a continuous-domain model, capable of accessing the spatiotemporal scales relevant to fuzz formation on the surface of plasma-facing component (PFC) tungsten, we report self-consistent simulation results that elucidate the effects of elastic softening and helium (He) accumulation kinetics on the surface morphological response of PFC tungsten. The model accounts for the softening of the elastic moduli in the near-surface region of PFC tungsten, including both thermal softening at high temperature and softening due to He accumulation upon He implantation. The dependence of the elastic moduli on the He content follows an exponential scaling relation predicted by molecular-dynamics simulations, while the He content in the near-surface region of PFC tungsten evolves according to a first-order saturation kinetics, consistent with experimental and simulation results reported in the literature. We establish that this elastic softening accelerates both nanotendril growth on the PFC surface and the onset of fuzz formation. We also explore the role of the rate of He accumulation to a saturation level in the near-surface region of irradiated tungsten in the onset of fuzz formation. For PFC tungsten surfaces such as W(110) where, under typical irradiation conditions, the characteristic time scale for stress-driven surface diffusion is comparable to the characteristic time scale for He accumulation, we find that accelerating the rate of He accumulation accelerates the growth rate of nanotendrils emanating from the surface. Additionally, we present a systematic parametric study of the PFC surface morphological response to explore its dependence on the He accumulation kinetics that is controlled by the irradiation conditions for low-energy implantation. Finally, we introduce an incubation time for nanotendril growth on the PFC surface, a concept equivalent to that of incubation fluence discussed in the literature, to predict and explain the minimum exposure time required to observe fuzz formation on PFC tungsten surfaces.

36 MATERIALS SCIENCE↗
DOE OSTI2022

High-Throughput Microfluidics Platform for Intracellular Delivery and Sampling of Biomolecules from Live Cells

Nondestructive cell membrane permeabilization systems enable the intracellular delivery of exogenous biomolecules for cell engineering tasks as well as the temporal sampling of cytosolic contents from live cells for the analysis of dynamic processes. Here, in this paper, we report a microwell array format live-cell analysis device (LCAD) that can perform localized-electroporation induced membrane permeabilization, for cellular delivery or sampling, and directly interfaces with surface-based biosensors for analyzing the extracted contents. We demonstrate the capabilities of the LCAD via an automated high-throughput workflow for multimodal analysis of live-cell dynamics, consisting of quantitative measurements of enzyme activity using self-assembled monolayers for MALDI mass spectrometry (SAMDI) and deep-learning enhanced imaging and analysis. By combining a fabrication protocol that enables robust assembly and operation of multilayer devices with embedded gold electrodes and an automated imaging workflow, we successfully deliver functional molecules (plasmid and siRNA) into live cells at multiple time-points and track their effect on gene expression and cell morphology temporally. Furthermore, we report sampling performance enhancements, achieving saturation levels of protein tyrosine phosphatase activity measured from as few as 60 cells, and demonstrate control over the amount of sampled contents by optimization of electroporation parameters using a lumped model. Lastly, we investigate the implications of cell morphology on electroporation-induced sampling of fluorescent molecules using a deep-learning enhanced image analysis workflow.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Direct Recycling of Spent NCM Cathodes through Ionothermal Lithiation

Ionic liquids (ILs) are a family of nonconventional molten salts that offer many advantages, such as negligible vapor pressures, negligible flammability, wide liquidus ranges, good thermal stability, and much synthesis flexibility. The unique solvation environment of these ILs provides new reaction or flux media for controlling formation of solid-state materials with a minimum perturbation of morphologies. A successful lithiation via ionothermal synthesis using a cost-effective Li halide as Li source and recyclable ILs as solvents is reported in this study for the direct recycling of LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM 111) cathodes. In addition, the ionic liquids can be readily recycled and reused after ionothermal lithiation. The lithiation of spent cathodes can enable the direct recycling of spent cathode materials in lithium-ion batteries.

25 ENERGY STORAGE↗
DOE OSTI2025

Design of Zn Chalcogenide Shells for Emissive Ga-Rich In 1– X Ga X As Quantum Dots Synthesized in Molten Salts

Colloidal quantum dots (QDs) have seen expanded applications in optoelectronics from visible to near-infrared (NIR) wavelengths. However, the options for QDs with bright and size-tunable emission in the NIR region are mostly limited to heavy-metal-based (Pb, Cd, Hg) semiconductors. Here, Ga-rich In 1–X Ga X As QDs with zinc chalcogenide shells are demonstrated as candidates for NIR emitters. Based on new developments in inorganic molten salt chemistry, we synthesized colloidal In 1–X Ga X As QDs containing up to 85% gallium with high crystallinity based on Raman and XRD analyses. Zinc selenide and sulfide shells with different morphologies were grown on In 1–X Ga X As QDs by controlling the Zn precursor chemistry. Despite the nominally reduced lattice mismatch in the In 1–X Ga X As/ZnSe heterostructure, a ZnS shell was found to be a much more effective passivation material: In 1–X Ga X As/ZnS core–shell QDs show a photoluminescence quantum yield (PL QY) of about 30% versus 11% for ZnSe shells. In conclusion, based on the analysis of PL decay and transient absorption (TA) dynamics, we surmise that electron trapping is the major reason for efficiency loss, providing a clear heterostructure design principle for realizing efficient NIR-emitting In 1–X Ga X As QDs.

Electron trapping↗
DOE OSTI2022

Direct Imaging of the Structural and Morphological Evolution of Epitaxial LiCoO 2 Films during Charge and Overcharge

The capacity decay of layered cathodes in high-voltage applications underscores the need to utilize accurate and precise techniques to understand the underlying mechanisms. Here, we use well-defined epitaxial LiCoO 2 (LCO) films on SrRuO 3 /SrTiO 3 (SRO/STO) with controlled orientations and defect structures along with in situ electrochemical atomic force microscopy to probe the structural and morphological evolutions during the charge and overcharge processes. We quantitatively show the morphological changes in both the reversible delithiation regime and the irreversible over-delithiation regime and correlate the overall electrochemical behaviors to atomic scale defect evolutions in the films. Further, we also observe a significantly lower charging capacity for LCO/SRO/STO(111) compared to that of LCO/SRO/STO(001) films of the same thickness, which is ascribed to different types of atomic scale defects formed during the film growth process. Our high- resolution scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) studies reveal that the antiphase boundaries in LCO/SRO/STO(111) act as viable channels for Li migration but are more susceptible to irreversible phase transitions, which then block subsequent Li diffusion. The failure mechanisms developed here may provide insight into the design of future cathode materials.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Explosive Soot Challenge (Final Report)

This project assembled a broad ensemble of modeling and experimentation tools to study the morphological and optical properties of detonation soots in explosive fireballs. A gram-scale hemispherical high explosive was studied in a low-pressure controlled environment using in-situ experimentation with diffusely illuminated visible absorption spectroscopy, particle sizing through light scattering techniques, and post-test collections with subsequent morphological analysis. Hydrocode modeling was performed to replicate the detonation flow observations, and subsequent aerosol kinetics models provided particle size distributions and extinction coefficients from the hydrocode results. Experimentally observed soot morphologies agreed with expectation from the literature - a bimodal distribution was found, brought upon by the particles growing to a size where their inertia and fluid wakes are non-negligible. The aerosol kinetics model did not replicate the observed bimodal size distribution for lack of a coagulation kernel to represent the behavior. To recover particulate optical properties, a spectrally resolved absorption spectroscopy method termed Spectral diffuse back-illuminated extinction imaging (SBI-EI) was developed and implemented on two explosive types. Inverting the absorption spectra using a Kramers-Kronig consistent method yielded the complex index of refraction for the soots produced by the explosives. This method resulted in an unrealistic index of refraction for one of the two explosives, and this is suspected to be due to the model neglecting scattering brought upon by the large particle sizes observed. In addition to the core work, three additional studies were performed in parallel. These investigated the impact of scattering on diffuse absorption spectroscopy, studied how soots oxidate and sublimate in a well-controlled shock tube, and laid the theoretical groundwork for a new collision kernel to replicate the bimodal size distribution from the observations. Summaries of these efforts are included at the end of this report.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2020

Tailorable Micelle Morphology in Self-Assembling Block Copolymer Gels for Templating Nanoporous Ceramics

The self-assembly of block copolymers offers opportunities for the facile organization and templating of inorganic nanomaterials. Here, we describe a morphology map for a poly(methyl methacrylate)-b-poly(n-butyl acrylate)-b-poly(methyl methacrylate) (PMMA-b-PnBA-b-PMMA) block copolymer/polycarbosilane system that allows for tunable control over nanoscale micelle geometry via manipulation of the preceramic polymer content. We produced gels with spherical, wormlike, and bicontinuous morphologies, which were processed to create silicon carbide-based ceramic structures with tunable nanoscale porosities. The role of the constituent polymers in influencing the structure and rheology of this system is discussed. The PMMA-b-PnBA-b-PMMA block copolymer/preceramic polymer system offers a number of advantages including: (i) commercial availability, (ii) rapid self-assembly kinetics, and (iii) successful conversion of the self-assembled nanostructure to ceramic via pyrolysis. Finally, this system may be useful for catalytic, structural, or thermal applications in both industrial and academic settings because of its ease of use and relatively inexpensive reagents.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Controlling Factors Analyses of Sediment Dispersal From Source-to-Sink Systems of Lacustrine Rift Basin: A Case Study From Paleogene Shahejie-Dongying Formations of Nanpu Sag, Eastern China

Tectonic activity not only shapes the basic stratigraphic framework of rift basins, but also profoundly affects the sediment dispersal in rift basins. In this study, analyses of heavy mineral assemblages in different periods demonstrate that there are three obvious tectono-sedimentary evolutionary stages (E s 3 –E s 2 , E s 1 –E d 2 , and E d 1 , respectively) in the Paleogene provenance area of Nanpu Sag, and the volume of sand bodies increases from the bottom of the Paleogene Shahejie (E s ) Formation to the top of the Dongying (E d ) Formation in Nanpu Sag. Besides, this study comprehensively utilize the analyses of seismic interpretation, palynology, heavy mineral, and borehole core samples to investigate the controlling factors of sediment dispersal in the rift basin. The assemblages of heavy minerals in different periods reflect the rock composition and catchment area of different provenance areas, and their vertical differences reflect the evolution process of the provenance area and reflect the uplift-denudation process of the provenance area. The results reveal that the synergy of the evolution of tectonic activity and the adjustment of topographical evolution are the main controlling factors of sediment dispersal in Nanpu Sag, while climate change is not the main controlling factor. We conclude that an increased sediment supply rate in the long term reflects the control of tectonic activity on basin topography, rather than climate fluctuations. The differences in morphological modification result in differential sediment dispersal, which is principally related to the differential extrusion of the fault system. The catchment area and provenance distance adjustment is evidenced by the vertical changes of heavy mineral characteristics of single-well and interaction and linkage of boundary faults, and the adjustment of topography evolution. A consideration is that the interaction and linkage of boundary faults and complex subsidence history are multi-directional, and differential evolution of provenance area is universal in lacustrine rift basins, all of this highlights the adjustment of sediment pathways generated by this characteristic of rift basins and emphasizes the importance of controlling factors analyses in understanding differential sediment dispersal that presents in the rift basins. Besides, four sets of sediment dispersal patterns were delineated based on different developmental regions in the rift basin, which are fault segmental point and multi-stage fault terrace, single-stage fault terrace and axial fault valley, axial fault terrace, and paleo-terrace and axial fault valley, respectively. This study has a certain guiding significance for the prediction of the spatial distribution of sand bodies in the rift basin and the exploration of potential oil and gas targets in the rift basin.

Yu, Jifeng↗