3,4‐Phenylenedioxythiophene (PheDOT) Based Hole‐Transporting Materials for Perovskite Solar Cells

Two new electron‐rich molecules based on 3,4‐phenylenedioxythiophene (PheDOT) were synthesized and successfully adopted as hole‐transporting materials (HTMs) in perovskite solar cells (PSCs). X‐ray diffraction, absorption spectra, photoluminescence spectra, electrochemical properties, thermal stabilities, hole mobilities, conductivities, and photovoltaic parameters of PSCs based on these two HTMs were compared with each other. By introducing methoxy substituents into the main skeleton, the energy levels of PheDOT‐core HTM were tuned to match with the perovskite, and its hole mobility was also improved (1.33×10^?4 cm² V^?1 s^?1, being higher than that of spiro‐OMeTAD, 2.34×10^?5 cm² V^?1 s^?1). The PSC based on MeO‐PheDOT as HTM exhibits a short‐circuit current density (J_sc) of 18.31 mA cm^?2, an open‐circuit potential (V_oc) of 0.914 V, and a fill factor (FF) of 0.636, yielding an encouraging power conversion efficiency (PCE) of 10.64 % under AM 1.5G illumination. These results give some insight into how the molecular structures of HTMs affect their performances and pave the way for developing high‐efficiency and low‐cost HTMs for PSCs.     

Azatruxene-Based,Dumbbell-Shaped,Donor–π-Bridge–Donor Hole-Transporting Materials for Perovskite Solar Cells

Three novel donor–π-bridge–donor (D -π-D) hole-transporting materials (HTMs) featuring triazatruxene electron-donating units bridged by different 3,4-ethylenedioxythiophene (EDOT) π-conjugated linkers have been synthesized, characterized, and implemented in mesoporous perovskite solar cells (PSCs). The optoelectronic properties of the new dumbbell-shaped derivatives (DTTXs) are highly influenced by the chemical structure of the EDOT-based linker. Red-shifted absorption and emission and a stronger donor ability were observed in passing from DTTX-1 to DTTX-2 due to the extended π-conjugation. DTTX-3 featured an intramolecular charge transfer between the external triazatruxene units and the azomethine–EDOT central scaffold, resulting in a more pronounced redshift. The three new derivatives have been tested in combination with the state-of-the-art triple-cation perovskite [(FAPbI₃)_0.87(MAPbBr₃)_0.13]_0.92[CsPbI₃]_0.08 in standard mesoporous PSCs. Remarkable power conversion efficiencies of 17.48 % and 18.30 % were measured for DTTX-1 and DTTX-2 , respectively, close to that measured for the benchmarking HTM spiro-OMeTAD (18.92 %), under 100 mA cm⁻² AM 1.5G solar illumination. PSCs with DTTX-3 reached a PCE value of 12.68 %, which is attributed to the poorer film formation in comparison to DTTX-1 and DTTX-2 . These PCE values are in perfect agreement with the conductivity and hole mobility values determined for the new compounds and spiro-OMeTAD. Steady-state photoluminescence further confirmed the potential of DTTX-1 and DTTX-2 for hole-transport applications as an alternative to spiro-OMeTAD.     

Direct C−H Arylation Meets Perovskite Solar Cells: Tin‐Free Synthesis Shortcut to High‐Performance Hole‐Transporting Materials

In contrast to the traditional multistep synthesis, we demonstrate herein a two‐step synthesis shortcut to triphenylamine‐based hole‐transporting materials (HTMs) through sequential direct C?H arylations. These hole‐transporting molecules are fabricated in perovskite‐based solar cells (PSCs) that exhibit promising efficiencies up to 17.69 %, which is comparable to PSCs utilizing commercially available 2,2′,7,7′‐tetrakis[N,N‐di(4‐methoxyphenyl)amino]‐9,9′‐spirobifluorene (spiro‐OMeTAD) as the HTM. This is the first report describing the use of step‐saving C?H activations/arylations in the facile synthesis of small‐molecule HTMs for perovskite solar cells.     

Butterfly-like Shape Liquid Crystals Based Fused-Thiophene as Unidimensional Ambipolar Organic Semiconductors with High Mobility

Mesomorphous butterfly-like shape molecules based on benzodithiophene, benzodithiophene-4,8-dione and cyclopentadithiophen-4-one core moieties were efficiently synthesized by the Suzuki-Miyaura coupling and Scholl oxidative cyclo-dehydrogenation reactions’ tandem. Most of the butterfly molecules spontaneously self-organize into columnar hexagonal mesophase. The electron-deficient systems possess strong solvent-gelling ability but are not luminescent, whereas the electron-rich terms do not form gels but strongly emit light between 400 and 600 nm. The charge carrier mobility was also measured by time-of-flight transient photocurrent technique in the mesophases for some of the compounds. They display hole-transport performances with positive charge mobility in the 10⁻³ cm⁻² V⁻¹ s⁻¹ range, consistent with the high degree of ordering and stability of the columnar superstructures. In particular, the mesogen with a benzodithiophen-4,8-dione core shows ambipolar charge carrier transport with both high electron (μ_e=6.6×10⁻³ cm⁻² V⁻¹ s⁻¹) and hole (μ_h=4.5×10⁻³ cm⁻² V⁻¹ s⁻¹) mobility values.     

Extending the π-Conjugated System in Spiro-Type Hole Transport Material Enhances the Efficiency and Stability of Perovskite Solar Modules

Hole transport materials (HTMs) are a key component of perovskite solar cells (PSCs). The small molecular 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl)-amine-9,9′-spirobifluorene (spiro-OMeTAD, termed “Spiro”) is the most successful HTM used in PSCs, but its versatility is imperfect. To improve its performance, we developed a novel spiro-type HTM (termed “DP”) by substituting four anisole units on Spiro with 4-methoxybiphenyl moieties. By extending the π-conjugation of Spiro in this way, the HOMO level of the HTM matches well with the perovskite valence band, enhancing hole mobility and increasing the glass transition temperature. DP-based PSC achieves high power conversion efficiencies (PCEs) of 25.24 % for small-area (0.06 cm²) devices and 21.86 % for modules (designated area of 27.56 cm²), along with the certified efficiency of 21.78 % on a designated area of 27.86 cm². The encapsulated DP-based devices maintain 95.1 % of the initial performance under ISOS-L-1 conditions after 2560 hours and 87 % at the ISOS-L-3 conditions over 600 hours.     

Charge transport properties of triphenylamine‐pendant polypeptide

The structurally ordered polymer, triphenylamine‐pendant polypeptide (PATPA: poly[γ‐4‐(N,N‐diphenylamino‐phenyl)‐L ‐glutamine]), was prepared in order to obtain high hole mobility and high thermal stability. The hole mobility obtained for PATPA (ca. 10⁻⁵ cm²/Vsec) at room temperature is higher than that for poly(N‐vinylcarbazole) (PVK) (ca. 10⁻⁷ cm²/Vsec) or that of carbazole‐pendant polypeptide (PCLG) (ca. 10⁻⁸ cm²/Vsec). These results are supported by thermally stimulated current (TSC) measurements because the TSC can be correlated with the mobility. The glass‐transition temperature (T_g) of PATPA was estimated to be about 130° by differential scanning calorimetry (DSC). From these results, PATPA is an alternative candidate as a photoconductive polymer with high thermal stability and high hole mobility. The ordered structure along the main chain is thought to facilitate hole transport. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 362–368, 2000     

Economical and Environmentally Friendly Organic hydrazone Derivatives Characterized by a Heteroaromatic Core as Potential Hole Transporting Materials in Perovskite Solar Cells

A series of organic electron-rich π-bridged symmetric hydrazones, composed of two donor moieties connected through a thiophene- or a pyrrole-based π-spacer, has been synthesized as a suitable alternative to 2,2’,7,7’-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9’-spirobifluorene ( Spiro-OMeTAD ), considered the benchmark hole transporting material (HTM) in perovskite solar cells (PSCs). The cheap synthetic protocol is suitable for potential large-scale production. All the compounds were characterized, showing good energy levels alignments with the perovskite and very close energy levels to the Spiro-OMeTAD . Furthermore, computational analysis confirmed the electrochemical trend observed. The costs of synthesis were estimated, as well as the produced waste to synthesise the final HTMs, underlining the low impact of these compounds on the environment with the respect to Spiro-OMeTAD . Overall, the relevant electrochemical properties and the low cost of the synthetic approaches allow these compounds to be a greener and easy-to-synthesize alternative to the Spiro-OMeTAD for industrial development of PSCs.     

Tuning Hole Transport Properties via Pyrrole Derivation for High-Performance Perovskite Solar Cells

Hole transport materials (HTMs) with high hole mobility, good band alignment and ease of fabrication are highly desirable for perovskite solar cells (PSCs). Here, we designed and synthesized novel organic HTMs, named T3, which can be synthesized in high yields with commercially available materials, featuring a substituted pyrrole core and triphenylamine peripheral arms. The capability of functionalization in the final synthetic step provides an efficient way to obtain a variety of T3-based HTMs with tunable energy levels and other properties. Among them, fluorine-substituted T3 (T3-F) exhibits the best band alignment and hole extraction properties, leading to PSCs with outstanding PCEs of 24.85 % and 24.03 % (certified 23.46 %) for aperture areas of 0.1 and 1 cm², respectively. The simple structure and tunable performance of T3 can inspire further optimization for efficient PSCs.     

Hole transport of trans-1,2-biscarbazolylcyclobutane-doped poly(bisphenol A carbonate) film

The hole transport of trans-1,2-biscarbazolylcyclobutane (CB) doped poly(bisphenol A carbonate) (PC) film has been investigated in the CB concentration range of 3.8 × 10^?4 mol cm^?3 (12 wt%) to 1.6 × 10^?3 mol cm^?3 (51 wt%). The hole mobility increased drastically with increasing CB concentration. The hole mobility was analyzed by a random hopping model. The localization radius ρ₀ of the CB/PC system was 1.9 Å, which is larger than that obtained for the N-isopropyl-carbazole-doped PC system. This suggests that the larger localization radius of the CB/PC system is related to the larger spatial extent of the CB molecule. The highest hole mobility of 2.9 × 10^?6 cm² V^?1 s^?1 was obtained when the CB concentration was 1.6 × 10^?3 mol cm^?3 (51 wt%) at E = 1.6 × 10⁵ V cm^?1 and T = 298 K. This mobility is about 10 times higher than that of poly(N-vinylcarbazole) (PVCz). The activation energy of hole mobility for the CB/PC system decreased with increasing CB concentration and was 0.31 eV at 51 wt% of CB, which is lower than the 0.45 eV for PVCz. The low activation energy for the CB/PC system is ascribed to the absence of an excimer-forming site that works as a multiple-trapping site for hole carriers.     

Silaindacenodithiophene‐Based Fused‐Ring Non‐Fullerene Electron Acceptor for Efficient Polymer Solar Cells

In this work, a new A‐D‐A type nonfullerene small molecular acceptor SiIDT‐IC, with a fused‐ring silaindacenodithiophene (SiIDT) as D unit and 2‐(3‐oxo‐2,3‐dihydroinden‐1‐ylidene)malononitrile (INCN) as the end A unit, was design and synthesized. The SiIDT‐IC film shows absorption peak and edge at 695 and 733 nm, respectively. The HOMO and LUMO of SiIDT‐IC are of −5.47 and −3.78 eV, respectively. Compared with carbon‐bridging, the Si‐bridging can result in an upper‐lying LUMO level of an acceptor, which is benefit to achieve a higher open‐circuit voltage in polymer solar cells (PSCs). Complementary absorption and suitable energy level alignment between SiIDT‐IC and wide bandgap polymer donor PBDB‐T were found. For the PBDB‐T:SiIDT‐IC based inverted PSCs, a D/A ratio of 1: 1 was optimal to achieve a power conversion efficiency (PCE) of 7.27%. With thermal annealing (TA) of the blend film, a higher PCE of 8.16% could be realized due to increasing of both short‐circuit current density and fill factor. After the TA treatment, hole and electron mobilities were elevated to 3.42 × 10⁻⁴ and 1.02 × 10⁻⁴ cm²·V⁻¹·s⁻¹, respectively. The results suggest that the SiIDT, a Si‐bridged fused ring, is a valuable D unit to construct efficient nonfullerene acceptors for PSCs.     

Polycyclic Arenes Dihydrodinaphthopentacene-based Hole-Transporting Materials for Perovskite Solar Cells Application

In this paper, two D-π-D type compounds, C1 and C2 , containing dihydrodinaphthopentacene (DHDNP) as a π-bridge, p-methoxydiphenylamine and p-methoxytriphenylamine groups as the donor groups were synthesized. The four 4-hexylphenyl groups at the sp³-carbon bridges of DHDNP were acquainted with control morphology and improving solubility. The light absorption, energy level, thermal properties, and application as hole-transporting materials in perovskite solar cells of these compounds were fully investigated. The HOMO/LUMO levels and energy gaps of these DHDNP-based molecules are suitable for use as hole-transporting materials in PSCs. The best power conversion efficiencies of the PVSCs based on the C1 and C2 are 15.96% and 12.86%, respectively. The performance of C1 is comparable to that of the reference compound spiro-OMeTAD (16.38%). Compared with spiro-OMeTAD, the C1 -based PVSC device showed good stability, which was slightly decreased to 98.68% of its initial efficiency after 48 h and retained 81% of its original PCE after 334 h without encapsulation. These results reveal the potential usefulness of the DHDNP building block for further development of economical and highly efficient HTMs for PVSCs.     

Azobenzene–Hemicyanine Conjugated Polymeric Chemosensor for the Rapid and Selective Detection of Cyanide in Pure Aqueous Media

A water-soluble polymeric probe was designed and synthesized that can be used for the colorimetric selective detection of cyanide ions in pure aqueous media. In particular, P1, a water-soluble random terpolymer (P1) of N,N′-dimethylacrylamide, 2-((E)-4-((E)-(4-((2-(acryloyloxy)ethyl)(methyl)amino)phenyl)diazenyl)styryl)-1,3,3-trimethyl-3H-indol-1-ium (M1), and N-(4-benzoylphenyl)acrylamide was synthesized via traditional free-radical polymerization. Upon the addition of CN⁻ ions to a P1 solution, a macroscopically detectable color change of the solution from brick red to light yellow took place, which was associated with a low limit of analyte detection (1.23 μM). Notably, P1 exhibited excellent selectivity toward CN⁻ over other anions and biothiols, which may be present in the medium. Such highly selective colorimetric response to CN⁻ by P1 originated from the nucleophilic attack of CN⁻ anions onto the electron-deficient polarized CN bonds of P1's indolium moieties, resulting in the perturbation of the intramolecular charge transfer process occurring within the probe via destruction of the polymer's extended π-conjugation. P1 was also immobilized on a quartz slide by spin coating and then exposed to ultraviolet light. The resulting polymeric film displayed a rapid response to CN⁻ consisting in a distinct color change, extending the scope of the usefulness of P1 as a cyanide-ion probe beyond the solution phase. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 124–131     

Conjoint use of Naphthalene Diimide and Fullerene Derivatives to Generate Organic Semiconductors for n–type Organic Thin Film Transistors

In this paper, we described the design, synthesis, and characterization of two novel naphthalene diimide (NDI) core-based targets modified with terminal fullerene (C₆₀) yield – so called S4 and S5 , in which NDI bearing 1 and 2 molecules of C₆₀, respectively. The absorption, electrochemical and thin-film transistor characteristics of the newly developed targets were investigated in detail. Both S4 and S5 displayed broad absorption in the 450–500 nm region, owing to the effect of conjugation due to fullerene functionalities. The electrochemical measurement suggested that the HOMO and the LUMO energy levels can be altered with the number of C₆₀ units. Both S4 and S5 were employed as organic semiconductor materials in n-channel transistors. The thin film transistor based on S4 exhibited superior electron mobility (μe) values ranging from 1.20×10⁻⁴ to 3.58×10⁻⁴ cm² V⁻¹ s⁻¹ with a current on-off ratio varying from 10² to 10³ in comparison with the performance of S5 based transistor, which exhibited μe ranging from 8.33×10⁻⁵ to 2.03×10⁻⁴ cm² V⁻¹ s⁻¹ depending on channel lengths.     

Electron-Deficient Polycyclic Molecules via Ring Fusion for n-Type Organic Electrochemical Transistors

The primary challenge for n-type small-molecule organic electrochemical transistors (OECTs) is to improve their electron mobilities and thus the key figure of merit μC*. Nevertheless, few reports in OECTs have specially proposed to address this issue. Herein, we report a 10-ring-fused polycyclic π-system consisting of the core of naphthalene bis-isatin dimer and the terminal moieties of rhodanine, which features intramolecular noncovalent interactions, high π-delocalization and strong electron-deficient characteristics. We find that this extended π-conjugated system using the ring fusion strategy displays improved electron mobilities up to 0.043 cm² V⁻¹ s⁻¹ compared to our previously reported small molecule gNR, and thereby leads to a remarkable μC* of 10.3 F cm⁻¹ V⁻¹ s⁻¹ in n-type OECTs, which is the highest value reported to date for small-molecule OECTs. This work highlights the importance of π-conjugation extension in polycyclic-fused molecules for enhancing the performance of n-type small-molecule OECTs.     

Kinetics of the gas‐phase reactions of Cl atom with selected C2–C5 unsaturated hydrocarbons at 283 < T < 323 K

The reaction of Cl atoms with a series of C₂–C₅ unsaturated hydrocarbons has been investigated at atmospheric pressure of 760 Torr over the temperature range 283–323 K in air and N₂ diluents. The decay of the hydrocarbons was followed using a gas chromatograph with a flame ionization detector (GC‐FID), and the kinetic constants were determined using a relative rate technique with n‐hexane as a reference compound. The Cl atoms were generated by UV photolysis (λ ≥ 300 nm) of Cl₂ molecules. The following absolute rate constants (in units of 10⁻¹¹ cm³ molecule⁻¹ s⁻¹, with errors representing ±2σ) for the reaction at 295 ± 2 K have been derived from the relative rate constants combined to the value 34.5 × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ for the Cl + n‐hexane reaction: ethene (9.3 ± 0.6), propyne (22.1 ± 0.3), propene (27.6 ± 0.6), 1‐butene (35.2 ± 0.7), and 1‐pentene (48.3 ± 0.8). The temperature dependence of the reactions can be expressed as simple Arrhenius expressions (in units of 10⁻¹¹ cm³ molecule⁻¹ s⁻¹): k_ethene = (0.39 ± 0.22) × 10⁻¹¹ exp{(226 ± 42)/T}, k_propyne = (4.1 ± 2.5) × 10⁻¹¹ exp{(118 ± 45)/T}, k_propene = (1.6 ± 1.8) × 10⁻¹¹ exp{(203 ± 79)/T}, k_1‐butene = (1.1 ± 1.3) × 10⁻¹¹ exp{(245 ± 90)/T}, and k_1‐pentene = (4.0 ± 2.2) × 10⁻¹¹ exp{(423 ± 68)/T}. The applicability of our results to tropospheric chemistry is discussed. © 2000 John Wiley & Sons, Inc. Int J Chem Kinet 32: 478–484, 2000     

Dithieno[3,2‐b:2′,3′‐d]pyrrole Cored p‐Type Semiconductors Enabling 20 % Efficiency Dopant‐Free Perovskite Solar Cells

Organic p‐type semiconductors with tunable structures offer great opportunities for hybrid perovskite solar cells (PVSCs). We report herein two dithieno[3,2‐b:2′,3′‐d]pyrrole (DTP) cored molecular semiconductors prepared through π‐conjugation extension and an N‐alkylation strategy. The as‐prepared conjugated molecules exhibit a highest occupied molecular orbital (HOMO) level of ?4.82 eV and a hole mobility up to 2.16×10^?4 cm² V^?1 s^?1. Together with excellent film‐forming and over 99 % photoluminescence quenching efficiency on perovskite, the DTP based semiconductors work efficiently as hole‐transporting materials (HTMs) for n‐i‐p structured PVSCs. Their dopant‐free MA_0.7FA_0.3PbI_2.85Br_0.15 devices exhibit a power conversion efficiency over 20 %, representing one of the highest values for un‐doped molecular HTMs based PVSCs. This work demonstrates the great potential of using a DTP core in designing efficient semiconductors for dopant‐free PVSCs.     

Quantitative Analysis of Holmium Ion by a Ho3+ Ion‐Selective Sensor Based on a Symmetric Thio‐Schiff's Base

A poly(vinyl chloride) (PVC) membrane sensor for holmium ions was fabricated based on N‐[(Z)‐1‐(2‐thienyl)‐ methylidene]‐N‐[4‐(4‐{[(Z)‐1‐(2‐thienyl)methylidene]amino} phenoxy)phenyl] amine (TPA) as a new ion carrier, acetophenon (AP) as plasticizing solvent mediator and sodium tetraphenyl borate (NaTPB) as an anion excluder. The electrode shows a good selectivity towards Ho³⁺ ions respect to other inorganic cations, including alkali, alkaline earth, transition and heavy metal ions. The constructed sensor displays a Nernstian behavior (19.5±0.3 mV/decade) over the concentration range of 1.0×10⁻⁶ to 1.0×10⁻² mol·L⁻¹ with the detection limit of the electrode being 4.6×10⁻⁷ mol·L⁻¹ and very short response time (ca. 5 s). It has a useful working pH range of 3.2–9.8 for at least 8 weeks. The electrode was successfully applied as an indicator electrode for the potentiometric titration of a Ho³⁺ solution with EDTA and holmium determination in some alloys. The proposed sensor accuracy was studied by the determination of Ho³⁺ in mixtures of three different ions.     

Positional Effect of the Triphenylamine Group on the Optical and Charge‐Transfer Properties of Thiophene‐Based Hole‐Transporting Materials

Hybrid organic‐inorganic perovskite solar cells (PSCs) have shown significant potential for use in the energy field. Typically, hole‐transporting materials (HTMs) play an important role in affecting the power conversion efficiency (PCE) of PSCs. A deep understanding of the structure‐property relationship plays a vital role in developing efficient HTMs. Herein, the relationship between the structure and properties of two small organic HTMs H2,5 and H3,4 were systematically investigated in terms of the electronic and optical properties, the hole‐transporting behavior by using density functional theory (DFT) and Marcus electron transfer theory. The results demonstrated that the high power conversion efficiency of the H2,5‐ based PSC was caused by strong interactions with the perovskite material on the interface and an enhanced hole mobility in H2,5 compared with H3,4 . The strong interaction derives from the short bond length of O atom of HTM and Pb atom of perovskite material, and the highly hole mobility derives from the quasi‐planar conjugated conformation and tight packing model of neighboring molecules in H2,5 . In addition, we found that the planar structure enhances the intermolecular interaction between HTM and perovskite materials compared with the ′V′‐shaped molecule. Importantly, we also note that the HOMO level of the isolated molecule is not always proportional to the open‐circuit voltages of PSCs since the HOMO level might move toward a higher level when the interaction between HTM and interface of perovskite was included. The work gives essential information for rational designing efficient HTMs.     

A 2D cadmium metal–organic framework: Synthesis,structure and luminescence sensing for chromate,permanganate, cupric,silver and ferric

A multi-responsive Cd metal–organic framework {[Cd (ttpe)(H₂O)(ip)]•4H₂O•DMAC}_n ( 1•4H ₂ O•DMAC ) was synthesized using hydrothermal method (ttpe = 1,1,2,2-tetra(4-(1H-1,2,4-triazol-1-yl)phenyl)ethylene, ip = isophthalate, DMAC = N,N-dimethylacetamide), and characterized. 1 exhibits a 2D (4,4) network. The luminescent sensing experimrnts showed that 1•4H ₂ O•DMAC as a new MOF luminescent sensor can detect Cr₂O₇²⁻, CrO₄²⁻, MnO₄⁻, Cu²⁺, Ag⁺ and Fe³⁺ in aqueous solution with simultaneously high efficiency and high sensitivity. The quenching constants K_sv for Cr₂O₇²⁻, CrO₄²⁻, MnO₄⁻, Cu²⁺, Ag⁺ and Fe³⁺ are 4.231 × 10⁴ M⁻¹, 2.471 × 10⁴ M⁻¹, 6.459 × 10³ M⁻¹, 7.617 × 10³ M⁻¹, 1.563 × 10⁴ M⁻¹ and 3.574 × 10⁴ M⁻¹, respectively. The detection limits are 0.094 μM for Cr₂O₇²⁻, 0.108 μM for CrO₄^{2 −} , 0.346 μM for MnO₄⁻, 0.302 μM for Cu²⁺, 0.221 μM for Ag ⁺ , and 0.100 μM for Fe³⁺. 1•4H ₂ O•DMAC exhibits high photocatalytic efficiency for degradation of methylene blue under visible light irradiation.     

Rate constants for the reactions of OH radicals and Cl atoms with Di‐n‐Propyl ether and Di‐n‐Butyl ether and their deuterated analogs

Using relative rate methods, rate constants for the gas‐phase reactions of OH radicals and Cl atoms with di‐n‐propyl ether, di‐n‐propyl ether‐d₁₄, di‐n‐butyl ether and di‐n‐butyl ether‐d₁₈ have been measured at 296 ± 2 K and atmospheric pressure of air. The rate constants obtained (in cm³ molecule⁻¹ s⁻¹ units) were: OH radical reactions, di‐n‐propyl ether, (2.18 ± 0.17) × 10⁻¹¹; di‐n‐propyl ether‐d₁₄, (1.13 ± 0.06) × 10⁻¹¹; di‐n‐butyl ether, (3.30 ± 0.25) × 10⁻¹¹; and di‐n‐butyl ether‐d₁₈, (1.49 ± 0.12) × 10⁻¹¹; Cl atom reactions, di‐n‐propyl ether, (3.83 ± 0.05) × 10⁻¹⁰; di‐n‐propyl ether‐d₁₄, (2.84 ± 0.31) × 10⁻¹⁰; di‐n‐butyl ether, (5.15 ± 0.05) × 10⁻¹⁰; and di‐n‐butyl ether‐d₁₈, (4.03 ± 0.06) × 10⁻¹⁰. The rate constants for the di‐n‐propyl ether and di‐n‐butyl ether reactions are in agreement with literature data, and the deuterium isotope effects are consistent with H‐atom abstraction being the rate‐determining steps for both the OH radical and Cl atom reactions. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 425–431, 1999