Hydrothermal synthesis of the microporous aluminophosphate CoAPO-5; in situ time-resolved synchrotron X-ray powder diffraction studies

In Situ Multinuclear Magic-Angle Spinning NMR: Monitoring Crystallization of Molecular Sieve AlPO4-11 in Real Time

Molecular sieves are crystalline three-dimensional frameworks with well-defined channels and cavities. They have been widely used in industry for many applications such as gas separation/purification, ion exchange, and catalysis. Obviously, understanding the formation mechanisms is fundamentally important. High-resolution solid-state NMR spectroscopy is a powerful method for the study of molecular sieves. However, due to technical challenges, the vast majority of the high-resolution solid-state NMR studies on molecular sieve crystallization are ex situ. In the present work, using a new commercially available NMR rotor that can withhold high pressure and high temperature, we examined the formation of molecular sieve AlPO₄-11 under dry gel conversion conditions by in situ multinuclear (¹H, ²⁷Al, ³¹P, and ¹³C) magic-angle spinning (MAS) solid-state NMR. In situ high-resolution NMR spectra obtained as a function of heating time provide much insights underlying the crystallization mechanism of AlPO₄-11. Specifically, in situ ²⁷Al and ³¹P MAS NMR along with ¹H → ³¹P cross-polarization (CP) MAS NMR were used to monitor the evolution of the local environments of framework Al and P, in situ ¹H → ¹³C CP MAS NMR to follow the behavior of the organic structure directing agent, and in situ ¹H MAS NMR to unveil the effect of water content on crystallization kinetics. The in situ MAS NMR results lead to a better understanding of the formation of AlPO₄-11.

In Situ Cs and H Exchange into Gaidonnayite and Proposed Mechanisms of Ion Diffusion

The microporous mineral gaidonnayite Na₂ZrSi₃O₉·2H₂O was studied to better understand its ion-exchange mechanisms, specifically for Cs⁺ and H⁺ ions. In situ Raman spectroscopy, in situ X-ray diffraction (XRD), simultaneous thermogravimetric analysis and differential scanning calorimetry (TGA/DSC), and in situ X-ray fluorescence were used to determine the exchange processes involved. The Raman spectra contain strong peaks that can be attributed to the vibrational modes for the 3MR symmetric stretch at 500 cm^-1, Si-O-Zr-O chain stretches at 938 cm^-1, and Si-O stretching in the 1000-1100 cm^-1 range. The most prominent Raman shift during ion exchange is found near the 520 cm^-1 peak, which corresponds to distortions of the 3MR substructure of gaidonnayite. In all instances of this study, the 3MR exhibited the highest amount of distortion during ion exchange, and the evolution of this distortion is compared to unit-cell changes as measured from XRD data and elemental changes via XRF. The correlations between the Raman, XRD, and XRF data show rapid deformation of the 3MR during the onset of H⁺ ion exchange in the Na form of gaidonnayite. Even when unit-cell volume changes were small (<3 ų) as in the cases for Cs⁺ into Na-gaidonnayite and Cs⁺ into H-gaidonnayite, significant changes in the ≈520 cm^-1 peak were measured. By comparing XRD data and Raman data, and verifying the cation uptake by XRF, we were able to identify and confirm conformational changes and distortions in the crystal structure before, during, and after Cs⁺ and H⁺ exchange. Cs exchange occurred the fastest and with the greatest capacity when starting in the H-form at room temperature, and at elevated temperatures when starting in the Na-form.

Systematic study of the crystallization process of CrAPO-5 using in situ high resolution X-ray diffraction

Systematic study of the hydrothermal crystallization process of CrAPO-5 by in situ high resolution X-ray powder diffraction (HRXRD).

The First 20 Hours of Geopolymerization: An in Situ WAXS Study of Flyash-Based Geopolymers

This study followed the first 20 h of flyash geopolymerization at 70 °C using time resolved Wide Angle X-ray Scattering (WAXS). The extent of dissolution of the amorphous phase of the flyash was determined to range from 29% to 54% for the different formulations trialed. The dissolution rate of the flyash significantly reduced after the first 5 h for all samples. During the formation stage of the geopolymer there were significant temporal variations in the chemistry of the dissolved solution due to the rate of flyash dissolution, with a relative standard deviation of 20%, 57% and 24% for the Si/Al, Na/Al and H/Si ratios, respectively. Utilizing the Power Law, scattering in the low angle region of the WAXS pattern combined with the geopolymer peak area yielded a measure which correlated with the compressive strength—providing a new method to measure the flyash dissolution and geopolymer formation processes independently. The evolution of several zeolite-like phases was followed, noting there are different formation mechanisms involved even within the same sample. Four samples were examined with compressive strengths ranging from 14(2)–50(9) MPa, each was synthesized with flyash from Collie Power Station (Western Australia) activated with sodium silicate solution of varying concentrations.

A versatile environmental control cell forin situguest exchange single-crystal diffraction

In situsingle-crystal diffraction experiments provide researchers with the opportunity to study the response of crystalline systems, including metal–organic frameworks and other nanoporous materials, to changing local microenvironments. This paper reports a new environmental control cell that is remarkably easy to use, completely reusable, and capable of delivering static or dynamic vacuum, liquids or gases to a single-crystal sample. Furthermore the device is nearly identical in size to standard single-crystal mounts so a full unrestricted range of motion is expected for most commercial goniometers.In situsingle-crystal X-ray diffraction experiments performed under dynamic gas-flow conditions revealed the cell was capable of stabilizing a novel metastable intermediate in the dehydration reaction of a previously reported metal–organic framework.

Catalyst characterisation techniques and reaction cells operating at realistic conditions; towards acquisition of kinetically relevant information

Catalyst characterisation techniques and reaction cells operating at realistic conditions; towards acquisition of kinetically relevant information.

In situ studies of solvothermal synthesis of energy materials

Solvothermal and hydrothermal synthesis, that is, synthesis taking place in a solvent at elevated temperature and pressure, is a powerful technique for the production of advanced energy materials as it is versatile, cheap, and environmentally friendly. However, the fundamental reaction mechanisms dictating particle formation and growth under solvothermal conditions are not well understood. In order to produce tailor-made materials with specific properties for advanced energy technologies, it is essential to obtain an improved understanding of these processes and, in this context, in situ studies are an important tool as they provide real time information on the reactions taking place. Here, we present a review of the use of powder diffraction and total scattering methods for in situ studies of synthesis taking place under solvothermal and hydrothermal conditions. The experimental setups used for in situ X-ray and neutron studies are presented, and methods of data analysis are described. Special attention is given to the methods used to extract structural information from the data, for example, Rietveld refinement, whole powder pattern modelling and pair distribution function analysis. Examples of in situ studies are presented to illustrate the types of chemical insight that can be obtained.

Synchrotron high energy X-ray methods coupled to phase sensitive analysis to characterize aging of solid catalysts with enhanced sensitivity

X-ray absorption spectroscopy and X-ray diffraction are suitable probes of the chemical state of a catalyst under working conditions but are limited to bulk information. Here we show in two case studies related to hydrothermal aging and chemical modification of model automotive catalysts that enhanced detailed information of structural changes can be obtained when the two methods are combined with a concentration modulated excitation (cME) approach and phase sensitive detection (PSD). The catalysts are subject to a modulation experiment consisting of the periodic variation of the gas feed composition to the catalyst and the time-resolved data are additionally treated by PSD. In the case of a 2 wt% Rh/Al2O3 catalyst, a very small fraction (ca. 2%) of Rh remaining exposed at the alumina surface after hydrothermal aging at 1273 K can be detected by PSD. This Rh is sensitive to the red-ox oscillations of the experiment and is likely responsible for the observed catalytic activity and selectivity during NO reduction by CO. In the case of a 1.6 wt% Pd/Al2O3-Ce(1-x)Zr(x)O2 catalyst, preliminary results of cME-XRD demonstrate that access to the kinetics of the whole material at work can be obtained. Both the red-ox processes involving the oxygen storage support and the Pd component can be followed with great precision. PSD enables the differentiation between Pd deposited on Al2O3 or on Ce(1-x)Zr(x)O2. Modification of the catalyst by phosphorous clearly induces loss of the structural dynamics required for oxygen storage capacity that is provided by the Ce(4+)/Ce(3+) pair. The two case studies demonstrate that detailed kinetics of subtle changes can be uncovered by the combination of in situ X-ray absorption and high energy diffraction methods with PSD.

A flow-through reaction cell for in situ X-ray diffraction and absorption studies of heterogeneous powder-liquid reactions and phase transformations

A portable powder-liquid high-corrosion-resistant reaction cell has been designed to follow in situ reactions by X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS) techniques. The cell has been conceived to be mounted on the experimental stations for diffraction and absorption of the Spanish CRG SpLine-BM25 beamline at the European Synchrotron Radiation Facility. Powder reactants and/or products are kept at a fixed position in a vertical geometry in the X-ray pathway by a porous membrane, under forced liquid reflux circulation. Owing to the short pathway of the X-ray beam through the cell, XRD and XAS measurements can be carried out in transmission configuration/mode. In the case of the diffraction technique, data can be collected with either a point detector or a two-dimensional CCD detector, depending on specific experimental requirements in terms of space or time resolution. Crystallization processes, heterogeneous catalytic processes and several varieties of experiments can be followed by these techniques with this cell. Two experiments were carried out to demonstrate the cell feasibility: the phase transformations of layered titanium phosphates in boiling aqueous solutions of phosphoric acid, and the reaction of copper carbonate and L-isoleucine amino acid powders in boiling aqueous solution. In this last case the shrinking of the solid reactants and the formation of Cu(isoleucine)(2) is observed. The crystallization processes and several phase transitions have been observed during the experiments, as well as an unexpected reaction pathway.

Experimental setup forin situX-ray SAXS/WAXS/PDF studies of the formation and growth of nanoparticles in near- and supercritical fluids

The growing interest in inorganic nanoparticles for a wide range of applications is spurring a need for synthesis methods that allow a highly specific tailoring of material properties. Synthesis in supercritical fluids holds great promise for solving this problem, but so far the fundamental chemical processes taking place under these conditions are to a large extent unknown. Here the design, construction and application of a versatile experimental setup are reported; this setup enablesin situsynchrotron small-angle X-ray scattering/wide-angle X-ray scattering/pair distribution function (SAXS/WAXS/PDF) studies of the formation and growth of nanoparticles under supercritical fluid conditions.

In Situ SAXS/WAXS of Zeolite Microwave Synthesis: NaY, NaA, and Beta Zeolites

A custom waveguide apparatus is constructed to study the microwave synthesis of zeolites by in situ small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS). The WR-284 waveguide is used to heat precursor solutions using microwaves at a frequency of 2.45 GHz. The reaction vessels are designed to include sections of thin-walled glass, which permit X-rays to pass through the precursor solutions with minimal attenuation. Slots were machined into the waveguide to provide windows for X-ray energy to enter and scatter from solutions during microwave heating. The synthesis of zeolites with conventional heating is also studied using X-ray scattering in the same reactor. SAXS studies show that the crystallization of beta zeolite and NaY zeolite is preceded by a reorganization of nanosized particles in their precursor solutions or gels. The evolution of these particles during the nucleation and crystallization stages of zeolite formation depends on the properties of the precursor solution. The synthesis of NaA and NaX zeolites and sodalite from a single zeolite precursor is studied by microwave and conventional heating. Microwave heating shifts the selectivity of this synthesis in favor of NaA and NaX over sodalite; conventional heating leads to the formation of sodalite for synthesis from the same precursor. The use of microwave heating also led to a more rapid onset of NaA zeolite product crystallization compared to conventional heating. Pulsed and continuous microwave heating are compared for zeolite synthesis. The resulting rates of formation of the zeolite products, and the relative amounts of the products determined from the WAXS spectra, are similar when either pulsed or continuous microwave heating is applied in the reactor while maintaining the same synthesis temperature. The consequences of these results in terms of zeolite synthesis are discussed.

A Comparative Investigation of Co2+ and Mn2+ Incorporation into Aluminophosphates by in Situ XAS and DFT Computation

The incorporation processes of Mn2+ and Co2+ into the framework of aluminophosphate molecular sieve AlPO4-5, at the onset of crystallization, were investigated by in situ synchrotron X-ray absorption spectroscopy (XAS) and density functional theory (DFT) computation. The results indicated that the syntheses of MnAPO-5 and CoAPO-5 were different in the incorporation mechanism of metal ions. For the synthesis of CoAPO-5, Co2+ transferred from an octahedral into tetrahedral structure with crystal formation, while, for MnAPO-5, the Mn2+ transition to the tetrahedral structure was much more difficult and it occurred after the appearance of long-range ordered microporous structure. The DFT computations of model intermediates involved in the synthesis process suggested that much higher transformation energy of [Mn(OP(OH)3)4]2+ than that of [Co(OP(OH)3)4]2+ was responsible for the diversity of the incorporation behaviors.

In situ Synthesis of Mixed-Valent Manganese Oxide Nanocrystals: An In situ Synchrotron X-ray Diffraction Study

Phase transformations of materials can be studied by in situ synchrotron X-ray diffraction. However, most reported in situ synchrotron XRD studies focus on solid state/gel systems by measuring phase/structure changes during application of pressure or heat. Phase transformations during material synthesis and their applications, especially in wet chemistry processes with different media, have not drawn much attention. Here, using manganese oxides as examples, we report the successful characterization of phase transformations in in situ hydrothermal synthesis conditions by the in situ synchrotron XRD method using a quartz/sapphire capillary tube as the synthesis reactor. The results were used for better design of materials with controlled structures and properties. This method can be generally used for synthesis of manganese oxides as well as for in situ characterization of other material syntheses using hydrothermal, sol-gel, and other methods. In addition, catalytic processes in liquid-solid, gas-solid, and solid-solid systems can also be studied in such an in situ way so that catalytic mechanisms can be better understood and catalyst synthesis and catalytic processes can be optimized.

In situtime-resolved characterization of Au–CeO2 and AuOx–CeO2 catalysts during the water-gas shift reaction: Presence of Au and O vacancies in the active phase

Synchrotron-based in situ time-resolved x-ray diffraction and x-ray absorption spectroscopies were used to study the behavior of nanostructured {Au+AuO(x)}-CeO(2) catalysts under the water-gas shift (WGS) reaction. At temperatures above 250 degrees C, a complete AuO(x)-->Au transformation was observed with high catalytic activity. Photoemission results for the oxidation and reduction of Au nanoparticles supported on rough ceria films or a CeO(2)(111) single crystal corroborate that cationic Au(delta+) species cannot be the key sites responsible for the WGS activity at high temperatures. The rate determining steps for the WGS seem to occur at the gold-ceria interface, with the active sites involving small gold clusters (<2 nm) and O vacancies.

Unraveling the Crystallization Mechanism of CoAPO-5 Molecular Sieves under Hydrothermal Conditions

The hydrothermal crystallization of CoAPO-5 molecular sieves has been studied using time-resolved in-situ SAXS/WAXS, UV-vis, Raman, and XAS. Data collected during heating to 180 degrees C allowed the observation of different steps occurring during the transformation of the amorphous gel into a crystalline material from a macroscopic and atomic perspective. Raman spectroscopy detected the initial formation of Al-O-P bonds, whereas SAXS showed that these gel particles had a broad size distribution ranging from ca. 7 to 20 nm before crystallization began. WAXS showed that this crystallization was sharp and occurred at around 160 degrees C. Analysis of the crystallization kinetics suggested a one-dimensional growth process. XAS showed that Co(2+) transformed via a two-stage process during heating involving (i) a gradual transformation of octahedral coordination into tetrahedral coordination before the appearance of Bragg peaks corresponding to AFI, suggesting progressive incorporation of Co(2+) into the poorly ordered Al-O-P network up to ca. 150 degrees C, and (ii) a rapid transformation of remaining octahedral Co(2+) at the onset of crystallization. Co(2+) was observed to retard crystallization of AFI but provided valuable information regarding the synthesis process by acting as an internal probe. A three-stage, one-dimensional crystallization mechanism is proposed: (i) an initial reaction between aluminum and phosphate units forming a primary amorphous phase, (ii) progressive condensation of linear Al-O-P chains forming a poorly ordered structure separated by template molecules up to ca. 155 degrees C, and (iii) rapid internal reorganization of the aluminophosphate network leading to crystallization of the AFI crystal structure.

The structural and electronic properties of nanostructured Ce1−x−yZrxTbyO2 ternary oxides: Unusual concentration of Tb3+ and metal↔oxygen↔metal interactions

Ceria-based ternary oxides are widely used in many areas of chemistry, physics, and materials science. Synchrotron-based time-resolved x-ray diffraction, x-ray absorption near-edge spectroscopy (XANES), Raman spectroscopy, and density-functional calculations were used to study the structural and electronic properties of Ce-Zr-Tb oxide nanoparticles. The nanoparticles were synthesized following a novel microemulsion method and had sizes in the range of 4-7 nm. The Ce1-x-yZrxTbyO2 ternary systems exhibit a complex behavior that cannot be predicted as a simple extrapolation of the properties of Ce1-xZrxO2, Ce1-xTbxO2, or the individual oxides (CeO2, ZrO2, and TbO2). The doping of ceria with Zr and Tb induces a decrease in the unit cell, but there are large positive deviations with respect to the cell parameters predicted by Vegard's rule for ideal solid solutions. The presence of Zr and Tb generates strain in the ceria lattice through the creation of crystal imperfections and O vacancies. The O K-edge and Tb LIII-edge XANES spectra for the Ce1-x-yZrxTbyO2 nanoparticles point to the existence of distinctive electronic properties. In Ce1-x-yZrxTbyO2 there is an unexpected high concentration of Tb3+, which is not seen in TbO2 or Ce1-xTbxO2 and enhances the chemical reactivity of the ternary oxide. Tb<-->O<-->Zr interactions produce a stabilization of the Tb(4f,5d) states that is responsible for the high concentration of Tb(3+) cations. The behavior of Ce1-x-yZrxTbyO2 illustrates how important can be metal<-->oxygen<-->metal interactions for determining the structural, electronic, and chemical properties of a ternary oxide.

The behavior of mixed-metal oxides: Physical and chemical properties of bulk Ce1−xTbxO2 and nanoparticles of Ce1−xTbxOy

The physical and chemical properties of bulk Ce(1-x)Tb(x)O(2) and Ce(1-x)Tb(x)O(y) nanoparticles (x<or =0.5) were investigated using synchrotron-based x-ray diffraction (XRD), x-ray adsorption near edge spectroscopy (XANES), Raman spectroscopy (RS), and first-principles density-functional (DF) calculations. DF results and Raman spectra point to a small tetragonal distortion after introducing terbium in ceria. The results of XRD show a small contraction (< or = 0.08 A) in the cell dimensions. The presence of Tb generates strain in the lattice through the variation of the ionic radii and creation of crystal imperfections and O vacancies. The strain increases with the content of Tb and affects the chemical reactivity of the Ce(1-x)Tb(x)O(y) nanoparticles towards hydrogen, SO(2), and NO(2). DF calculations for bulk Ce(1-x)Tb(x)O(2) and Ce(8-n)Tb(n)O(16) (n=0, 1, 2, or 4) clusters show oxide systems that are not fully ionic. The theoretical results and XANES spectra indicate that neither a Ce<-->Tb exchange nor the introduction of oxygen vacancies in Ce(1-x)Tb(x)O(y) significantly affect the charge on the Ce cations. In contrast, the O K-edge and Tb L(III)-edge XANES spectra for Ce(1-x)Tb(x)O(y) nanoparticles show substantial changes with respect to the corresponding spectra of Ce and Tb single oxide references. The Ce(0.5)Tb(0.5)O(y) compounds exhibit a much larger Tb(3+)/Tb(4+) ratio than TbO(1.7). A comparison with the properties of Ce(1-x)Zr(x)O(y) and Ce(1-x)Ca(x)O(y) shows important differences in the charge distribution, the magnitude of the dopant induced strain in the oxide lattice, and a superior behavior in the case of the Ce(1-x)Tb(x)O(y) systems. The Tb-containing oxides combine stability at high temperature against phase segregation and a reasonable concentration of O vacancies, making them attractive for chemical and catalytic applications.

Reduction of CuO and Cu2O with H2: H embedding and kinetic effects in the formation of suboxides

Time-resolved X-ray diffraction, X-ray absorption fine structure, and first-principles density functional calculations were used to investigate the reaction of CuO and Cu(2)O with H(2) in detail. The mechanism for the reduction of CuO is complex, involving an induction period and the embedding of H into the bulk of the oxide. The in-situ experiments show that, under a normal supply of hydrogen, CuO reduces directly to metallic Cu without formation of an intermediate or suboxide (i.e., no Cu(4)O(3) or Cu(2)O). The reduction of CuO is easier than the reduction of Cu(2)O. The apparent activation energy for the reduction of CuO is about 14.5 kcal/mol, while the value is 27.4 kcal/mol for Cu(2)O. During the reduction of CuO, the system can reach metastable states (MS) and react with hydrogen instead of forming Cu(2)O. To see the formation of Cu(2)O, one has to limit the flow of hydrogen, slowing the rate of reduction to allow a MS --> Cu(2)O transformation. These results show the importance of kinetic effects for the formation of well-defined suboxides during a reduction process and the activation of oxide catalysts.

Experimental and theoretical studies on the reaction of H(2) with NiO: role of O vacancies and mechanism for oxide reduction

Reduction of an oxide in hydrogen is a method frequently employed in the preparation of active catalysts and electronic devices. Synchrotron-based time-resolved X-ray diffraction (XRD), X-ray absorption fine structure (NEXAFS/EXAFS), photoemission, and first-principles density-functional (DF) slab calculations were used to study the reaction of H(2) with nickel oxide. In experiments with a NiO(100) crystal and NiO powders, oxide reduction is observed at atmospheric pressures and elevated temperatures (250-350 degrees C), but only after an induction period. The results of in situ time-resolved XRD and NEXAFS/EXAFS show a direct NiO-->Ni transformation without accumulation of any intermediate phase. During the induction period, surface defect sites are created that provide a high efficiency for the dissociation of H(2). A perfect NiO(100) surface, the most common face of nickel oxide, exhibits a negligible reactivity toward H(2). The presence of O vacancies leads to an increase in the adsorption energy of H(2) and substantially lowers the energy barrier associated with the cleavage of the H-H bond. At the same time, adsorbed hydrogen can induce the migration of O vacancies from the bulk to the surface of the oxide. A correlation is observed between the concentration of vacancies in the NiO lattice and the rate of oxide reduction. These results illustrate the complex role played by O vacancies in the mechanism for reduction of an oxide. The kinetic models frequently used to explain the existence of an induction time during the reduction process can be important, but a more relevant aspect is the initial production of active sites for the rapid dissociation of H(2).

Real time observation of the hydrothermal crystallization of barium titanate using in situ neutron powder diffraction

The hydrothermal crystallization of barium titanate, BaTiO3, has been studied in situ by time-resolved powder neutron diffraction methods using the recently developed Oxford/ISIS hydrothermal cell. This technique has allowed the formation of the ferroelectric ceramic to be followed in a noninvasive manner in real time and under genuine reaction conditions. In a first set of experiments, Ba(OD)2-8D2O was reacted with two different titanium sources, either crystalline TiO2 (anatase) or amorphous TiO2-H2O in D2O, at 100-140 degrees C and the reaction studied using the POLARIS time-of-flight neutron powder diffractometer, at the ISIS Facility. In a second series of experiments, the reaction between barium chloride and crystalline TiO2 (anatase) in NaOD/D2O was studied at temperatures between 100 and 200 degrees C and at different deuterioxide concentrations using the constant-wavelength D20 neutron powder diffractometer at the Institut Laue Langevin. Quantitative growth and decay curves were determined from analysis of the integrated intensities of Bragg reflections of starting materials and product phases. In both sets of experiments the rapid dissolution of the barium source was observed, followed by dissolution of the titanium source before the onset of crystallization of barium titanate. Using a nucleation-growth model we are able to simulate the growth curve of barium titanate at three temperatures. Our results indicate the predominance of a homogeneous dissolution-precipitation mechanism for the hydrothermal formation of barium titanate, rather than other possible mechanisms that have been discussed in the literature. Analysis of the line widths of the Bragg reflections in the neutron diffraction data indicates that the particle size of the BaTiO3 product phase prepared from the amorphous TiO2-H2O is smaller than that prepared from crystalline TiO2 (anatase).

Crystallization in Nonaqueous Media of Co- and Mn-Substituted Microporous Aluminophosphates Investigated by in Situ Synchrotron X-ray Powder Diffraction

In situ synchrotron X-ray powder diffraction was used to investigate the crystallization of microporous transition metal-substituted aluminophosphates from nonaqueous media. The gels contained ethylene glycol and triethylamine as the template and were heated in quartz glass capillaries at temperatures up to 200 degrees C. The following crystalline products were formed: MnAPO-5, [AFI], CoAPO-5, [AFI], and AlPO(4)-5, [AFI]. Three nonaqueous systems were investigated in situ, where the crystallization of MAPO-5-type materials were followed. Solvothermal crystallization of MnAPO-5 and CoAPO-5 was studied, and the effect of adding HF as a mineralizing agent was investigated. Time-resolved powder diffraction data were collected using a translating imaging plate (TIP) camera, and crystallization curves were extracted using integrated diffraction peaks. Kinetic analysis of the crystallization curves was performed using an Avrami-type expression, alpha(t) = exp(-(kt)(n)()). Apparent activation energies were determined from Arrhenius plots: MnAPO-5, 94 kJ/mol; MnAPO-5(HF), 68 kJ/mol; CoAPO-5, 61 kJ/mol. Crystallization of CoAPO-5 is faster than for MnAPO-5, and the values for n obtained by fitting with the Avrami-type expression were significantly lower for CoAPO-5 than for MnAPO-5.