# Supercritical Hydrothermal Synthesis of Spinel Type Cobalt Gallate Nanoparticles with Controlled  Crystal Defects and Their Magnetic Properties

https://mdr.nims.go.jp/datasets/d3eda5e9-2682-41f0-a891-4bd258b5d7c8

## File

- [【Crystal Growth  Design】draft_Proof_hi.pdf](https://mdr.nims.go.jp/filesets/77bb60a0-f394-450c-adb7-0450a234bdb0/download) ([Detail](https://mdr.nims.go.jp/filesets/77bb60a0-f394-450c-adb7-0450a234bdb0.md))

## Id

d3eda5e9-2682-41f0-a891-4bd258b5d7c8

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2023-12-01T05:53:20.473847Z

## Updated at

2024-01-05T13:13:29.648540Z

## Published at

2023-12-06T04:30:58.913912Z

## Doi

https://doi.org/10.48505/nims.4292

## First published url

https://doi.org/10.1021/acs.cgd.2c01435

## Date published

2023-04-05

## Recorded date published

2023-4-5

## Resource type

journal_article

## Manuscript type

authors_original

## Collection



## Title

- title: Supercritical Hydrothermal Synthesis of Spinel Type Cobalt Gallate Nanoparticles
    with Controlled  Crystal Defects and Their Magnetic Properties
  title_type: original
  lang: en

## Description

- description: There are significant ongoing studies on the production of spinel-type
    CoGa2O4 nanoparticles, regarding its enhanced properties that could be applied
    in fields such as gas sensing and electrocatalysis. To achieve a better performance,
    the implementation of defects like oxygen and metal vacancies could be considered.
    However, trials that have reported on the implementation of crystal defects within
    CoGa2O4 are extremely rare. In this work, we report the synthesis of spinel-type
    cobalt gallate nanoparticles (Co-Ga NPs) using a fast supercritical hydrothermal
    synthesis at around 400 ℃ for 10 min without performing the calcination process
    and effects of pH value of precursor solutions on the final solid production were
    investigated. As consequences, spinel-type Co-Ga NPs with controllable morphology,
    particle size (17~58 nm) and Co/Ga molar ratios were successfully produced using
    precursor solutions with various pH values. Based on the composition measurement
    by inductively coupled plasma (ICP), it was found that Co-Ga NPs produced from
    the precursor solutions with pH value of 7, 9 and 11, were having the Co/Ga molar
    ratios that significantly exceed the stoichiometric molar ratio of 1:2, which
    implied a totally different spinel-type crystal structure compared to CoGa2O4
    . Interestingly, Co-Ga NPs produced by the present technique exhibited a combined
    magnetic behavior of paramagnetism and ferromagnetism based on the results of
    magnetization measurements at room temperature. Moreover, prepared Co-Ga NPs were
    generated mainly from solid starting materials in the precursor solutions containing
    cobalt gallium nitrate layered double hydrates (Co-Ga-NO 3 - LDHs).
  description_type: abstract
  lang: eng

## Creator

- name: Bo Xie
  role: author
- name: Chiya Numako
  role: author
- name: Takashi Naka
  role: author
  orcid: https://orcid.org/0000-0002-0645-6952
  organization: National Institute for Materials Science
- name: Seiichi Takami
  role: author

## Contact agent



## Publisher

organization: American Chemical Society (ACS)

## Managing organization



## Keyword

- subject: supercritical hydrothermal synthesis
  schema: not_defined
- subject: nanoparticle
  schema: not_defined
- subject: magnetic properties
  schema: not_defined

## Rights

- description: This document is the unedited Author’s version of a Submitted Work
    that was subsequently accepted for publication in Crystal Growth & Design, copyright
    © 2023 The Authors. Published by American Chemical Society after peer review.
    To access the final edited and published work see https://doi.org/10.1021/acs.cgd.2c01435.
  identifier: http://rightsstatements.org/vocab/InC/1.0/

## Other identifier(s)



## Data origin

- data_origin_type: other

## Embargo



## Journal

- title: CRYSTAL GROWTH & DESIGN
  issn: '15287483'
  volume: '23'
  issue: '4'
  start_page: 2511
  end_page: 2521

## Conference



## Related item



## Funding



## 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: 77bb60a0-f394-450c-adb7-0450a234bdb0
  filename: "【Crystal Growth  Design】draft_Proof_hi.pdf"
  content_type: application/pdf
  size: 4056515
  md5: bc2d6aff60a8a6a2b06dd7f83ca511b7

## Thumbnail

fileset_id: 77bb60a0-f394-450c-adb7-0450a234bdb0
filename: "【Crystal Growth  Design】draft_Proof_hi.pdf"