Controlled Phase Transformation Research Articles

Nanoscale phase transformation in SiC wafer by spatiotemporal tailored ultrafast laser pulses for multiple optical data encryption

Color center has shown great potential in optical data encryption due to its tunable optical performance. In this work, precise and controllable implantation of color centers within 4H-SiC wafers has been demonstrated by spatiotemporal tailored ultrafast laser irradiation. Distinct microstructures via micro-ablation, micro-cracking and internal phase transformation can be achieved by precisely regulating the spatial energy input in SiC wafer. The orientation of generated microstructures can be accurately controlled by tuning the laser polarization directions. Those color centers can be further customized by varying the defocusing distances and pulse durations. Wherein, nanoscale amorphous carbon layer with thickness ~ 100 nm was achieved by ultrafast laser induced internal phase transformation, which was ascribed to an enhanced near-field optical effect. Due to the thin-film interference, various colors can display from pink to light-green in those laser modified samples with different carbon nanolayer depths. With the highly flexible and precise modification in SiC crystal, multiple colors can therefore be implanted to encode optical information at small scale, allowing high density and complex information storage. This represents a significant advance in controlled phase transformation for nanoscale color centers fabrication, which is promising in multiple optical data encryption.

Unraveling the multistage phase transformations in monolayer MoTe2−x

Monolayer MoTe2 exhibits a variety of derivative structural phases and associated intriguing electronic properties that enable a wealth of potential applications in future electronic and optoelectronic devices. However, a comprehensive study focusing on the complexities of the controllable phase evolution in this atomically thin film has yet to be performed. This work aims to address this issue by systematically investigating molecular beam epitaxial growth of monolayer Mo–Te compounds on bilayer graphene substrates. By utilizing scanning tunneling microscopy, we explored a series of thermally driven structural phase evolutions, including distinct T′-MoTe2, H-MoTe2, Mo6Te6 nanowires, and multistoichiometric MoTe2−x. Furthermore, we carefully investigated the critical effects of the growth parameters—annealing temperature and time and tellurium concentration—on the controllable and reversible phase transformation within monolayer MoTe2−x. The findings have significant implications for understanding the thin film synthesis and phase transformation engineering inherent to two-dimensional crystals, which can foster further development of high-performance devices.

Deciphering Indirect Nitrite Reduction to Ammonia in High-Entropy Electrocatalysts Using In Situ Raman and X-ray Absorption Spectroscopies.

This research adopts a new method combining calcination and pulsed laser irradiation in liquids to induce a controlled phase transformation of Fe, Co, Ni, Cu, and Mn transition-metal-based high-entropy Prussian blue analogs into single-phase spinel high-entropy oxide and face-centered cubic high-entropy alloy (HEA). The synthesized HEA, characterized by its highly conductive nature and reactive surface, demonstrates exceptional performance in capturing low-level nitrite (NO2 -) in an electrolyte, which leads to its efficient conversion into ammonium (NH4 +) with a Faradaic efficiency of 79.77% and N selectivity of 61.49% at -0.8 V versus Ag/AgCl. In addition, the HEA exhibits remarkable durability in the continuous nitrite reduction reaction (NO2 -RR), converting 79.35% of the initial NO2 - into NH4 + with an impressive yield of 1101.48 µm h-1 cm-2. By employing advanced X-ray absorption and in situ electrochemical Raman techniques, this study provides insights into the indirect NO2 -RR, highlighting the versatility and efficacy of HEA in sustainable electrochemical applications.

Preparation of NiTip/Al composites with controllable phase transformation and damping behavior by friction stir processing

Preparation of NiTip/Al composites with controllable phase transformation and damping behavior by friction stir processing

The defects of structural and phase transformations in polycrystalline cerium dioxide under heating in vacuum and in air

Structural changes in cerium dioxide, when heated in vacuum in the range of 25‒1600 °C, in air in the range of 25‒1500 °C, and during successive annealing in the range of 1600‒2100 °C in air, followed by quenching in water, were studied. In the crystal lattice of CeO2‒х, the F → F1 phase transformation in vacuum proceeds in the range of 1100‒1600 °C; additionally, at 1200 °C, X-ray lines of the C-type Ce2O3 phase appear. The thermal expansion coefficient of phases of the fluorite type F and F1 in the range of 25‒1500 °C in air, as well as phases of the fluorite type F, F1 and type C Ce2O3 in the range of 25‒1600 °C are determined in vacuum and their dependence on the change in the oxygen content in the CeO2‒х crystal lattice was found. The kinetic conditions for reduction of cerium dioxide in vacuum and oxidation in air are different. The cubic structure of the fluorite type F CeO2‒х, when the samples are heated in air, is preserved up to 1800 °C with the content of anionic vacancies, at 1900 °C the transformation F → F1 occurs. The formation of loops, edge and screw dislocations in the structure of cerium dioxide grains after annealing of samples in the range of 1900‒2100 °C in air were discovered for the first time. The decomposition of the structure F1 into cerium oxide phases of types F and C proceeds at 2100 °C along the height and boundaries of screw dislocations. It was found that fragments of the C-type phase of cerium oxide are located on loops along the height of screw dislocations, which indicates the movement and evaporation of these fragments. When the samples are oxidized at 1600 °C in air, the black-colored C Ce2O3‒х phase in a gradient of different concentrations moves along certain trajectories to opposite ones. grain boundaries, abuts against dislocation loops, bends them, and oxidizes to phases F1 and F. In the structure of polycrystalline cerium dioxide, when heated in vacuum and in air, certain concentrations of defects control phase transformations.

Achieving high-damping NiTip/7075Al composites with controllable phase transformation behavior fabricated by friction stir processing

To achieve controllable damping temperature zones in aluminum matrix composites, the NiTip/7075Al composites with controllable phase transformation characteristics were prepared through friction stir processing (FSP) and heat treatment. Aging of NiTi particles led to a downward shift in the phase-transition peak temperature of the composite, accompanied by a sharper peak. During the cooling process, the as-NiTip/7075Al + T6 composites underwent a B2 → R transformation and an R → B19′ transformation. Furthermore, the T6 treatment effectively enhanced the tensile strength of the composites. The damping properties of NiTip/7075Al composites at low-temperatures (<90 °C) were significantly superior to those of FSP-7075Al alloy. The as-NiTip/7075Al + T6 composites exhibited two internal friction peaks during cooling, which were 153 % and 211 % higher, respectively, than those observed in the FSP-7075Al alloy at corresponding temperatures. The damping temperature range of the composites can be effectively controlled through T6 treatment and NiTi particle pre-aging.

Controlled Phase Transformation and Crystal Growth of Titanium Dioxide from Anatase/Silica Core/Shell Particles.

Anatase/silica core/shell particles were prepared by the hydrolysis and condensation of tetraethyl orthosilicate on anatase particles with the sizes of 9, 22, and 111 nm, respectively. The thickness of the silica layer was designed from ca. 3 to 14 nm by repeating the coating procedure on anatase with a particle size of 22 nm. By the heat treatment at 1000 °C, though the pristine anatase particles transformed to rutile, anatase remained for the silica-coated particles. Anatase particles (111 nm) transformed to rutile upon heating at 1100 °C, while the transformation was not observed for the smaller particles (9 and 22 nm). With the increase of the silica thickness to 14 nm, anatase did not transform to rutile even after heating at 1150 °C, while resulting in varied compositions of anatase and rutile after heating at 1200 °C. The crystal growth of anatase and rutile was also suppressed for the silica-coated particles compared with that seen for pristine anatase. Thus, the thermal transformation and crystal growth of titania were controlled by the coating with silica, and the effects were shown to affect the coating.

Cation substitution-dependent phase transforming phosphors: A new alternative broadband NIR-II emitter for solid state lighting

Solid state broadband near-infrared radiation source has great application prospects in the field of agriculture, food and pharmaceutical industries, and health care. Here we report a series of broadband near-infrared luminescent phosphors with the formular of (Zn1−xMgx)Ga2−yO4:yNi (x = 0–1, y = 0.01–0.07) prepared by a high temperature solid-state reaction method. The Zn1−xMgxGa2O4 hosts were first synthesized with different ratios of Zn2+ to Mg2+. A panel of solid-state phosphors were synthesized by Ni2+ doping using a phase transformation method. The resulted phosphors have Ni2+ situated in varied crystal field environment which affected the luminescence behavior of Ni2+. Under the excitation of 365 nm, the phosphors emitted 1000–1600 nm near infrared (NIR) with a broad full width of half maximum (FWHM) of ∼ 250 nm, whose luminescence intensity was highly controllable phase transformation. The phosphor prepared with the optimal host composition and optimized Ni2+ doping concentration had an internal quantum yield of phosphor as high as ∼ 12 %, and its luminescence intensity at 393 K remained 50 % of that at room temperature. The as-prepared optimized phosphor was encapsulated with a 365 nm LED chip to obtain pc-NIR LED device, which emitted broadband NIR. Its application potential in biological imaging was demonstrated.

A novel solvent system of polyamides achieves new application in ZIBs by aggregation induced Lewis acid-base centers

Dissolutions of the polymer in the chaotropic salts follow Hofmeister effect, and the aggregate of salts and solvents shows new influence of the Hofmeister effect. Here, we reveal the aggregation of ion–solvent in chaotropic salt solution catalyzes the formation of the exposed Lewis acid-base center and realizes the dissolution of polyamide (PA) macromolecules. The relationship between Hofmeister effect, aggregate chemistry and Lewis acid-base chemistry is examined from new perspective. And then, a new solvent system and phase conversion process are designed for polyamides. Finally, the applications of PA in ZIBs as coating layer and binder are realized. As an electrode coating, it can effectively inhibit hydrogen evolution, corrosion and dendrite problems and improve the cycle life (cycle over 1500 h at 0.5 mA cm−2). As a binder, the active material adhesion on current collector, uniformity and wettability of the electrode are improved. The assembled pouch-cell with PANI cathode shows a capacity of 150 mAh g−1 after 120 cycles. This work reveals the secret of controlled phase transformation of polyamide in saline solution from a new perspective. And this phase conversion method is simpler, greener and more environmentally friendly, which greatly accelerates the application of polyamide in the field of membrane science and binder science.

Controllable Phase Transformation and Enhanced Photocatalytic Performance of Nano-TiO2 by Using Oxalic Acid.

Degradation of organic pollutants, especially organic dyes and antibiotics, by semiconductor photocatalysts is an efficient strategy for wastewater treatment. TiO2 nanomaterials are considered to be promising photocatalysts due to their high chemical stability, high efficiency and availability. Anatase TiO2 generally has superior photocatalytic activity to the rutile phase. However, the anatase phase can be irreversibly transformed to rutile phase when calcined at an elevated temperature. Methods to improve the stability of anatase are especially important for the TiO2 gas sensors working at high temperatures. The addition of strong acids can effectively suppress this transformation process. However, these strong acids are relatively expensive, corrosive and environmentally unfriendly. Herein, oxalic acid (OA) as a natural acid was used to control the hydrolysis process of tetrabutyl titanate (TBOT), leading to controllable crystalline phase transformation and reduced crystalline size of TiO2 on the nanoscale. What is more, the photocatalytic degradation performances were enhanced continuously when the molar ratio of OA to TBOT increased. The degradation reaction rate constants of CT650-R25 were about 10 times that of CT650-R0. The mechanism study shows that the enhanced photocatalytic activity can be attributed to the improved dispersibility, increased specific surface area and reduced recombination rates of photo-induced charge carriers and decreased energy bands as the concentration of OA increased. Thus, this work provides a simple, mild and effective method for controlling the crystalline forms of nano-TiO2 with enhanced photocatalytic performance towards waste water treatment.

Stereoactive Metallic Vanadium Oxide Barriers to Boost Silicon‐Based Lithium‐Ion Storage

AbstractDespite the intensive efforts devoted to confining silicon (Si)‐based materials with heteromatrices for high‐energy‐density lithium‐ion batteries, addressing practical issues with rationally incorporated stereoactive matrix is still a significant challenge. This study presents an electrochemical‐active, metallic matrix for boosting Si‐based lithium‐ion storage. By employing a straightforward strategy involving mechanical ball‐milling and controllable phase transformation, spatially confined Si‐based composites enabled by metallic vanadium oxide (VO0.9) barriers can be readily achieved. The scalable interface engineering allows for expanded transportation channels and maintained structural integrity, which can be well established in both SiOx and Si cases. Endowed with promoted electron conduction as well as fast lithium‐ion diffusion, the optimal Si‐based composite electrodes demonstrate remarkable lithium storage performance, that is, an initial Coulombic efficiency of 81%, and a high specific capacity of 1249 mAh g−1 at 500 mA g−1 after 100 cycles. Notably, full cells coupled with a commercial LiCoO2 cathode are demonstrated, affording impressive specific energy of 440 Wh kg−1 at high mass loading. This work provides a cost‐effective approach to promoting the practical application of Si‐based anodes, which also holds promise for extension towards energy‐related applications and beyond.

Methodology to Investigate the Transformation Plasticity for Numerical Modelling of Hot Forging Processes

Hot forging is a complex process involving the mutual influence of numerous thermo-mechanical-metallurgical material phenomena. In particular, the strains of transformation-induced plasticity (TRIP) have a significant influence on the distortions and residual stresses of the components. The TRIP strains refer to the anisotropic strains depending on the orientation and significance of the stress conditions during cooling superimposed to the phase transformation. With the use of numerical models, the impact of this effect can be investigated in order to ensure the production of high quality components. However, an experimental determination of the characteristic values of TRIP is challenging, which is why only few corresponding data are available in the literature. Therefore, this paper presents an experimental and numerical methodology as well as the results of studies on the interaction between stresses and phase transformations in the materials AISI 4140 and AISI 52100. The investigations of the TRIP strains are carried out using hollow specimens, which are thermo-mechanically treated in the physical forming simulator Gleeble 3800-GTC. The specimens are austenitised, quenched to test temperature and held there while diffusion controlled phase transformation takes place. The extent of TRIP as a result of different superimposed tensile or compressive loads is determined by means of dilatometry. In addition, the extent of TRIP for diffusionless martensitic phase transformations was investigated by continuous cooling tests under tensile and compressive loads. It was found that the transformation plasticity varies depending on the material, the phase type, the temperature and the tensile or compressive stresses. Subsequently, simulations of the physical experiments using the FE software Simufact.Forming verified the determined phase specific values of TRIP.

Design and noise-reduction simulation of an acoustic metamaterial plate incorporating tunable shape memory cantilever absorbers

Metamaterials are materials having artificially tailored internal structure and unusual physical and mechanical properties. Due to their unique characteristics, metamaterials possess great potential in engineering applications. This study proposes a tunable metamaterial for the applications in acoustic isolation. Therefore, a stopband in the dispersion curve can be created because of the energy gap. For the conventional metamaterial, the stopband is fixed. Although the metamaterial with tunable characteristics has been proposed in the literature to extend its working stopband, the efficacy is usually compromised. In this study, cantilevers of tunable shape memory materials (SMM) via controlled phase transformation are incorporated into the metamaterial plate. Its theoretical finite element formulation for determining the dynamic characteristics is established. The effect of the configuration of the SMM cantilever absorbers on the metamaterial plate for the desired stopband in wave propagation is simulated by using finite element model and a commercial multi-physics software. The result demonstrates the tunable capability on the stopband of the metamaterial plate under different activation controls of the SMM absorbers, and shows the ability to trap the vibration at the designed frequency and prevent vibration wave from propagating downstream in different absorber arrangements and alloy phases. It should be beneficial to precision machinery and defense industries which have desperate need in vibration and noise isolation.

Salt-Assisted 2H-to-1T' Phase Transformation of Transition Metal Dichalcogenides.

Phase engineering of nanomaterials (PEN) has demonstrated great potential in the fields of catalysis, electronics, energy storage and conversion, and condensed matter physics. Recently, transition metal dichalcogenides (TMDs) with unconventional metastable phases (e.g., 1T and 1T') have attracted increasing research interest due to their unique and appealing physicochemical properties. However, there is still a lack of a simple, universal, and controlled method for the preparation of large-scale and high-purity unconventional-phase TMD crystals, restricting their further fundamental study and practical applications. Here, a facile, one-step salt-assisted general strategy is reported for the controlled phase transformation of commercially available TMDs with conventional 2H phase, yielding a large amount of metastable 1T'-phase TMDs, including WS2 , WSe2 , MoS2 , and MoSe2 . It is found that the easily accessible metal salts, such as K2 C2 O4 ·H2 O, K2 CO3 , Na2 CO3 , Rb2 CO3 , Cs2 CO3 , KHCO3 , NaHCO3 , and NaC2 O4 , can be used to assist the 2H-to-1T' phase transformation, greatly simplifying the synthetic process for producing metastable 1T'-TMDs. Importantly, this method can also be used to prepare 1T'-TMD alloys, such as 1T'-WS2 x Se2(1- x ) . This newly developed strategy is robust and highly effective, which can also be used for the phase engineering of other materials with various polymorphs.

Self-supported VO(PO3)2 electrode for 2.8 V symmetric aqueous supercapacitors

Improving the voltage window of aqueous supercapacitors beyond 2.5 V without diminishing their capacitance performance is a big challenge to achieve excellent energy density because of the undesirable water decomposition. Herein, this study developed a novel vanadium phosphate (VPO) of the VO(PO3)2 aerogel as the electrode to enlarge the device voltage, which could effectively raise HER/OER overpotentials and thus achieving a stable wide electrochemical window of −1 ∼ 1 V (vs. SCE) with remarkably improved capacitance. The VPO microstructure is organized by nanowire-stacked lamellar bricks via engineering a controllable phase-transformation using the V-P-citric acid-aerogel as the precursor. Examined as the supercapacitor electrode, in-situ X-ray powder diffraction analysis uncovers that the VO(PO3)2 undergoes a reversible phase-transformation reaction associated with Na+ intercalation/de-intercalation in Na2SO4 and a typical redox pseudocapacitance process in KOH. For the first time, a 2.8 V symmetric aqueous supercapacitor was further assembled with an energy density of 123.1 Wh kg−1 at the power density of 580 W kg−1, which is much superior to those of all reported V-base supercapacitors. The underlying mechanisms of the VO(PO3)2 on ultrahigh voltage window and charge storage are further elucidated, which provide the fundamental guidance for structuring VPO-based electrodes used for commercial energy storage devices.

Enhancing the catalytic activity and CO2 chemisorption ability of the perovskite cathode for soild oxide electrolysis cell through in situ Fe-Sn alloy nanoparticles

Herein, the Sn-doped perovskite oxide Sr1.95Fe1.4Sn0.1Mo0.5O6-δ (SFSnM), which exhibited in situ exsolved Fe-Sn alloy nanoparticles and controllable phase transformation, was synthesized to catalyze the reduction of CO2 through A-site deficiency regulation. The in situ exsolved Fe-Sn alloy nanoparticles were uniformly distributed on the surface of the SFSnM substrate after reduction, which significantly enhanced the catalytic activity and CO2 adsorption capacity of the SFSnM cathode. Moreover, a single cell with an FeSn@SFSnM cathode exhibited excellent CO2 electrolysis performance, achieving a current density of 3.269 A cm−2 and an Rp value of 0.145 Ω cm2 at 800 °C and 1.8 V. Additionally, no significant performance attenuation was observed during a long-term stability test (200 h), indicating the good stability of FeSn@SFSnM cathode. Overall, these results demonstrated that the designed FeSn@SFSnM cathode shows great potential for high-performance solid oxide electrolysis cells (SOECs).

Laser additive manufacturing of bulk and powder ceramic materials: mathematical modeling with experimental correlations

PurposeThis paper aims to develop efficient and simple models for thermal distribution, melt pool dimensions and controlled phase change in the laser additive manufacturing (AM) of bulk and powder particles ceramic materials.Design/methodology/approachThis paper proposes new analytical models for the AM of bulk and powder bed ceramic materials. A volumetric moving heat source, along with the complete melting of bulk and powder particle materials, is taken into account. Different values of laser absorption coefficient in solid and liquid states have been used to investigate the phase transformation. Furthermore, the pores and voids dimensions are also included in the modeling. Theoretical predictions have been compared with the experimental analyses and finite element simulations in laser to silicon nitride and laser to alumina interaction. The analysis focuses on the impact of laser power and scanning speed on the melt pool width and depth evolution into the bulk substrate and powder bed.FindingsThis study shows that the powder particles exhibit a higher thermal distribution value than the bulk substrate because of voids in the powder layer. The laser beam experiences multiple reflections in the presence of porosity/voids, thus increasing the surface absorption coefficient, which becomes relevant with the increment in the pore/void dimension. A direct relationship has been found between the laser power and melt pool dimensions, while the scanning speed displayed an inverse relationship for the melt pool width and length. Larger melt dimensions were inferred in the case of laser–powder particle interaction compared with laser–bulk substrate interaction. A close correlation was found between the analytical simulations, experimental investigations and numerical simulation results within the range of 4%–8%.Originality/valueThis paper fulfills an identified need to develop efficient and simplified models for ceramics laser AM by taking into account different laser absorption coefficients in solid and liquid form, voids and pores dimensions and controlled phase transformation to avoid vapors and plasma formation. The limitation of the finite element simulation model is that the solution is strongly dependent on the mesh quality and accuracy directly linked to the computation efficiency and time. A finer mesh requires a longer computing time than a coarse mesh. Finite element simulations require, however, specialized skills.

Fabrication of Monetite by a Controlled Phase Transformation of Three Dimensionally Printed Calcium Sulfate Construct

M onetite is one of the calcium phosphates that has been used for bone regeneration and repair. Comparing to the widely used hydroxyapatite, monetite displayed greater resorption at physiological pH and could induce osteoclast resorption. Fabrication of a shape-customizable monetite construct by using a powder-based three dimensional printing (3DP) technique in combination with a phase transformation at low temperature was studied. Phase transformation of 3D printed calcium sulfate-based sample was carried out in 1M disodium hydrogen phosphate solution at pH5. Various processing parameters were then varied including temperatures (37 oC, 65 oC and 100 oC), sample weight to solution volume ratios (1:20, 1:30, 1:40 and 1:50) and soaking periods (24 h, 48 h, 72 h, 96 h and 120 h). It was found that a temperature of 100 oC, a sample weight to volume ratio of 1:50 and a time greater than 48 h were needed to fully transform the as-printed sample to monophasic monetite without causing the destruction of the structure or the incomplete transformation. Consistently, the microstructure of samples changed from rod-like crystals of calcium sulfate to petal-like crystals of monetite during the transformation process. Density, compressive modulus and strength decreased with soaking times during the course of transformation, but they did not further change with times after complete transformation. In vitro resorbability showed that 3D printed resorbed without conversion to other phase and its weight loss and ions release were greater than those of 3D printed hydroxyapatite indicating its greater resorption potential.

Achieving excellent cycle stability in Zr–Nb–Co–Ni based hydrogen isotope storage alloys by controllable phase transformation reaction

Hydrogen isotope (deuterium and tritium) as a special form of hydrogen energy, its storage in an efficient and safe way has been paid more and more attention by researchers in recent years. ZrCo alloy is regarding as the one and only promising material for large-scale storage of hydrogen isotope. However, poor cycle life and inferior capacity retention restrict its engineering application. Herein, we propose a co-substitution strategy of Nb (for Zr) and Ni (for Co) in ZrCo alloy to overcome the defects. Significantly, Zr0.8Nb0.2Co0.8Ni0.2 alloy exhibits ultralong cycle life (97.6% retention) and remarkable capacity (2.42 H (f. u.)) in 100 cycles, which far exceeds all existing hydrogen isotope storage alloys (Pd, U and other ZrCo-based alloys). These outstanding performances are entirely revealed from two aspects: stable homogeneous structural phase transformation process of parent structure (Zr0.8Nb0.2Co0.8Ni0.2H0.3-B33 ↔ Zr0.8Nb0.2Co0.8Ni0.2H2.8-B33″) and ordered migration mechanism of H atom (layered and linear de-/intercalation). Our attractive insights into the ultralong cycle life of ZrCo-based alloys through homogeneous structural phase transformation will serve as a pioneer on cycle optimization in the field of hydrogen storage materials.

Biomorphic Transformations: A Leap Forward in Getting Nanostructured 3-D Bioceramics.

Obtaining 3-D inorganic devices with designed chemical composition, complex geometry, hierarchic structure and effective mechanical performance is a major scientific goal, still prevented by insurmountable technological limitations. With particular respect to the biomedical field, there is a lack in solutions ensuring the regeneration of long, load-bearing bone segments such as the ones of limbs, due to the still unmet goal of converging, in a unique device, bioactive chemical composition, multi-scale cell-conducive porosity and a hierarchically organized architecture capable of bearing and managing complex mechanical loads in a unique 3D implant. An emerging, but still very poorly explored approach in this respect, is given by biomorphic transformation processes, aimed at converting natural structures into functional 3D inorganic constructs with smart mechanical performance. Recent studies highlighted the use of heterogeneous gas-solid reactions as a valuable approach to obtain effective transformation of natural woods into hierarchically structured apatitic bone scaffolds. In this light, the present review illustrates critical aspects related to the application of such heterogeneous reactions when occurring in the 3D state, showing the relevance of a thorough kinetic control to achieve controlled phase transformations while maintaining the multi-scale architecture and the outstanding mechanical performance of the starting natural structure. These first results encourage the further investigation towards the biologic structures optimized by nature along the ages and then the development of biomorphic transformations as a radically new approach to enable a technological breakthrough in various research fields and opening to still unexplored industrial applications.