TY - JOUR

T1 - Platinum(IV) Carbonato Complexes: Formation via the Addition of CO2 to the [Pt(OH)6]2- Anion and Generation of Platinum(IV) Oxide Nanoparticles for the Preparation of Catalysts

AU - Vasilchenko, Danila

AU - Tkachev, Sergey

AU - Tkachenko, Pavel

AU - Berdyugin, Semen

AU - Popovetskiy, Pavel

AU - Gerasimov, Evgeny

AU - Zhurenok, Angelina

AU - Kozlova, Ekaterina

N1 - This work was supported by the Russian Science Foundation (RSF grant 21-73-10038). The authors deeply thank Dr. P. E. Plusnin for his assistance with TG analysis, Dr. E. A. Maximovskiy for the collecting of SEM data, Dr. B. A. Kolesov for the recording of Raman spectra, T. Ya. Guselnikova for the help with ICP-AES analysis, and XRD Facility of NIIC SB RAS for the PXRD data collection.

PY - 2023/6/19

Y1 - 2023/6/19

N2 - A combination of multinuclear nuclear magnetic resonance spectroscopy and theoretical calculation based on density functional theory was used for a speciation study of Pt in solutions prepared either by the interaction of [Pt(OH)6]2- with gaseous CO2 in an alkaline solution of platinum(IV) hydroxide ([Pt(OH)4(H2O)2]) or by the dissolution of [Pt(OH)4(H2O)2] in an aqueous KHCO3 solution. The formed solutions contained coexisting Pt(IV) carbonato complexes with κ1- and κ2-coordination modes. The gradual condensation of mononuclear Pt species in such bicarbonate solutions resulted in the formation of PtO2 nanoparticles aggregating into a solid precipitate on prolonged aging. The deposition of PtO2 particles from bicarbonate solutions was adapted for the preparation of Pt-containing heterogeneous catalysts: bimetallic Pt-Ni catalysts were prepared using various supporting materials (CeO2, SiO2, and g-C3N4) and tested for the activity in hydrazine-hydrate decomposition. All prepared materials showed high selectivity with respect to H2 production from the hydrazine-hydrate with PtNi/CeO2 showing the highest rate of H2 evolution. In the long-range evaluation, the PtNi/CeO2 catalyst operating at 50 °C showed an exceptional turnover number value of 4600 producing hydrogen at a 97% selectivity level and with a mean turnover frequency value of about 470 h-1. In the case of the PtNi/g-C3N4 catalyst, for the first time, the photodriven decomposition of hydrazine-hydrate was shown to enhance the productivity of the catalyst by 40%.

AB - A combination of multinuclear nuclear magnetic resonance spectroscopy and theoretical calculation based on density functional theory was used for a speciation study of Pt in solutions prepared either by the interaction of [Pt(OH)6]2- with gaseous CO2 in an alkaline solution of platinum(IV) hydroxide ([Pt(OH)4(H2O)2]) or by the dissolution of [Pt(OH)4(H2O)2] in an aqueous KHCO3 solution. The formed solutions contained coexisting Pt(IV) carbonato complexes with κ1- and κ2-coordination modes. The gradual condensation of mononuclear Pt species in such bicarbonate solutions resulted in the formation of PtO2 nanoparticles aggregating into a solid precipitate on prolonged aging. The deposition of PtO2 particles from bicarbonate solutions was adapted for the preparation of Pt-containing heterogeneous catalysts: bimetallic Pt-Ni catalysts were prepared using various supporting materials (CeO2, SiO2, and g-C3N4) and tested for the activity in hydrazine-hydrate decomposition. All prepared materials showed high selectivity with respect to H2 production from the hydrazine-hydrate with PtNi/CeO2 showing the highest rate of H2 evolution. In the long-range evaluation, the PtNi/CeO2 catalyst operating at 50 °C showed an exceptional turnover number value of 4600 producing hydrogen at a 97% selectivity level and with a mean turnover frequency value of about 470 h-1. In the case of the PtNi/g-C3N4 catalyst, for the first time, the photodriven decomposition of hydrazine-hydrate was shown to enhance the productivity of the catalyst by 40%.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85163729265&origin=inward&txGid=de55990e1f44033e16af2c1e10c8fa08

UR - https://www.mendeley.com/catalogue/7928e625-7b4f-381e-bc98-3d67b57b3e86/

U2 - 10.1021/acs.inorgchem.3c01320

DO - 10.1021/acs.inorgchem.3c01320

M3 - Article

C2 - 37291758

VL - 62

SP - 9732

EP - 9748

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 24

ER -