# Lewis Acid–Base-Driven Anisotropic Crystal Growth of Pyrochlore Pb                    <sub>2</sub>                    Ti                    <sub>2</sub>                    O                    <sub>5.4</sub>                    F                    <sub>1.2</sub>                    with Enhanced Visible-Light H                    <sub>2</sub>                    Evolution Activity

https://mdr.nims.go.jp/datasets/f84dc651-3e29-49d9-8577-55417c13f621

## Files

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## Id

f84dc651-3e29-49d9-8577-55417c13f621

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2026-04-12T23:23:29.053900Z

## Updated at

2026-04-13T00:22:40.388563Z

## Published at

2026-04-13T01:23:12.639907Z

## Doi



## First published url

https://doi.org/10.1021/acs.chemmater.5c03153

## Date published

2026-02-24

## Recorded date published

2026-2-24

## Resource type

journal_article

## Manuscript type

vor

## Collection



## Title

- title: |-
    Lewis Acid–Base-Driven Anisotropic Crystal Growth of Pyrochlore Pb
                        <sub>2</sub>
                        Ti
                        <sub>2</sub>
                        O
                        <sub>5.4</sub>
                        F
                        <sub>1.2</sub>
                        with Enhanced Visible-Light H
                        <sub>2</sub>
                        Evolution Activity
  title_type: original
  lang: en

## Description

- description: Mixed-anion compounds offer unique functionalities unattainable with
    single-anion materials, yet rational morphology control remains largely unexplored.
    Here, we report a Lewis acid–base-driven strategy that enables low-temperature,
    solution-phase morphology control of the oxyfluoride photocatalyst Pb2Ti2O5.4F1.2
    (PTOF). A microwave-assisted solvothermal method with monoethanolamine (MEA) was
    used to tune the particle morphology and size via the precursor-solution pH, which
    was adjusted by the addition of formic acid or acetic acid. PTOF, an A2B2X6X′0.5-type
    pyrochlore with intrinsic anion vacancies (X′2, 4d site), has exposed {111} facets
    composed of alternating Pb-rich and Ti-rich layers. Lewis basic MEA is proposed
    to bind selectively to undercoordinated, strongly acidic Pb2+ sites adjacent to
    Ti4+ and vacancies on Ti-rich {111} facets, suppressing growth along the surface
    direction and stabilizing these facets, thereby driving anisotropic crystal growth
    and forming plate-like nanoparticles. At pH 10 (formic acid), PTOF nanoparticles
    (∼30 nm) with a specific surface area of 37 m2 g–1 were obtained. Compared with
    an analogous PTOF synthesized by a conventional solid–state reaction, the optimized
    sample exhibited ∼29-fold higher H2 evolution activity in an aqueous solution
    containing dissolved disodium ethylenediaminetetraacetate under visible-light
    (λ > 400 nm) with the aid of a Pt cocatalyst. Lewis acid–base-directed facet stabilization
    is thus shown to be a promising approach for the rational morphological design
    of mixed-anion oxyfluorides via solution processing.
  description_type: abstract
  lang: und

## Creator

- name: Gentoku Kido
  role: author
- name: Hiroto Ueki
  role: author
- name: Megumi Okazaki
  role: author
  orcid: https://orcid.org/0000-0003-1167-9453
- name: Jun Kikkawa
  role: author
  orcid: https://orcid.org/0000-0003-0659-1844
- name: Koji Kimoto
  role: author
  orcid: https://orcid.org/0000-0002-3927-0492
- name: Ryosuke Nishikubo
  role: author
  orcid: https://orcid.org/0000-0002-0533-9180
- name: Akinori Saeki
  role: author
  orcid: https://orcid.org/0000-0001-7429-2200
- name: Kazuhiko Maeda
  role: author
  orcid: https://orcid.org/0000-0001-7245-8318

## Contact agent



## Publisher

organization: American Chemical Society (ACS)

## Managing organization



## Keyword

- subject: Catalytic activity
  schema: not_defined
- subject: Nanoparticles
  schema: not_defined
- subject: Organic acids
  schema: not_defined
- subject: pH
  schema: not_defined
- subject: Photocatalysis
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by-nc-nd/4.0/

## Other identifier(s)



## Data origin



## Embargo



## Journal

- title: Chemistry of Materials
  issn: '08974756'
  volume: '38'
  issue: '4'
  start_page: 1980
  end_page: 1990

## Conference



## Related item



## Funding

- identifier: JP25H00899
  funder_name: Japan Society for the Promotion of Science
- identifier: JP22H05142
  funder_name: Japan Society for the Promotion of Science
- identifier: JP22H05145
  funder_name: Japan Society for the Promotion of Science
- identifier: JP22H05148
  funder_name: Japan Society for the Promotion of Science
- identifier: JP23H04626
  funder_name: Japan Society for the Promotion of Science

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



## Software



## Custom property



## Fileset

- id: dffd4d1f-4f33-4494-b1b0-37b7651a0e87
  filename: lewis-acid-base-driven-anisotropic-crystal-growth-of-pyrochlore-pb2ti2o5-4f1-2-with-enhanced-visible-light-h2-evolution.pdf
  content_type: application/pdf
  size: 8038503
  md5: d8518454801e412248448384aa946911

## Thumbnail

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