The Impact of Composition on the Photoelectrochemical Performance of Molybdenum-Modified Tungsten Oxide in Acidic Media

IF 2.7 4区化学 Q3 CHEMISTRY, PHYSICAL

Electrocatalysis Pub Date : 2025-02-03 DOI:10.1007/s12678-025-00931-z

Lalita Sharma, Kateřina Minhová Macounová, Roman Nebel, Petr Krtil

{"title":"The Impact of Composition on the Photoelectrochemical Performance of Molybdenum-Modified Tungsten Oxide in Acidic Media","authors":"Lalita Sharma, Kateřina Minhová Macounová, Roman Nebel, Petr Krtil","doi":"10.1007/s12678-025-00931-z","DOIUrl":null,"url":null,"abstract":"<div><p>The efficiency of photoelectrochemical (PEC) water splitting is considerably controlled by the recombination of photogenerated electron/hole charge carriers at the interface. Herein, the correlation between composition and photoelectrochemical activity is studied by utilizing molybdenum-modified tungsten oxide electrodes. Molybdenum tungsten mixed oxides (Mo<sub><i>x</i></sub>W<sub>1−<i>x</i></sub>O<sub>3</sub>) were synthesized by <i>spray-freeze/freeze-drying</i> approach by varying <i>x</i> from 0 to 1 and studied as a photoanode. The structural changes after Mo substitution in tungsten oxide (Mo<sub><i>x</i></sub>W<sub>1−<i>x</i></sub>O<sub>3</sub>; 0 ≤ <i>x</i> ≤ 1.0) were observed as a function of the composition. In binary oxides, monoclinic structure (ℽ-phase) was observed until Mo substitution (<i>x</i>) reached 0.2. A coexistence of both monoclinic and orthorhombic phases was observed for <i>x</i> varying from 0.2 to 0.8. All synthesized n-semiconducting materials were photoelectrochemically active in water splitting under the acidic condition of HClO<sub>4</sub>. The highest PEC activity was observed for the sample with low Mo content (<i>x</i> = 0.05) for which the narrowest band gap was determined. The overall activity decrease encountered for Mo-rich materials can be related to a higher tendency to photoinduced proton insertion facilitated by rhombohedral structure. The insight into the mechanism was determined by differential electrochemical mass spectrometry (DEMS). Oxygen (<i>m</i>/<i>z</i> 32) and hydrogen peroxide (<i>m</i>/<i>z</i> 34) were identified as main products. The material with small variation in compositions (<i>x</i> = 0.05) significantly influenced catalytic activity and selectivity, highlighting the importance of the material’s design.</p><h3>Graphical Abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":535,"journal":{"name":"Electrocatalysis","volume":"16 3","pages":"451 - 461"},"PeriodicalIF":2.7000,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12678-025-00931-z.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Electrocatalysis","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s12678-025-00931-z","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}

引用次数: 0

Abstract

The efficiency of photoelectrochemical (PEC) water splitting is considerably controlled by the recombination of photogenerated electron/hole charge carriers at the interface. Herein, the correlation between composition and photoelectrochemical activity is studied by utilizing molybdenum-modified tungsten oxide electrodes. Molybdenum tungsten mixed oxides (Mo_xW_1−xO₃) were synthesized by spray-freeze/freeze-drying approach by varying x from 0 to 1 and studied as a photoanode. The structural changes after Mo substitution in tungsten oxide (Mo_xW_1−xO₃; 0 ≤ x ≤ 1.0) were observed as a function of the composition. In binary oxides, monoclinic structure (ℽ-phase) was observed until Mo substitution (x) reached 0.2. A coexistence of both monoclinic and orthorhombic phases was observed for x varying from 0.2 to 0.8. All synthesized n-semiconducting materials were photoelectrochemically active in water splitting under the acidic condition of HClO₄. The highest PEC activity was observed for the sample with low Mo content (x = 0.05) for which the narrowest band gap was determined. The overall activity decrease encountered for Mo-rich materials can be related to a higher tendency to photoinduced proton insertion facilitated by rhombohedral structure. The insight into the mechanism was determined by differential electrochemical mass spectrometry (DEMS). Oxygen (m/z 32) and hydrogen peroxide (m/z 34) were identified as main products. The material with small variation in compositions (x = 0.05) significantly influenced catalytic activity and selectivity, highlighting the importance of the material’s design.

Graphical Abstract

查看原文本刊更多论文

组成对钼改性氧化钨在酸性介质中光电化学性能的影响

光电化学（PEC）分水效率在很大程度上受界面上光生成的电子/空穴电荷载流子重组的控制。本文利用钼改性氧化钨电极研究了成分与光电化学活性之间的相关性。钼钨混合氧化物（MoxW1-xO3）是通过喷雾冷冻/冷冻干燥方法合成的，x 值从 0 到 1 不等。观察了氧化钨（MoxW1-xO3；0 ≤ x ≤ 1.0）中钼取代后的结构变化与组成的函数关系。在二元氧化物中，观察到单斜结构（ℽ-相），直到钼取代度（x）达到 0.2。当 x 在 0.2 至 0.8 之间变化时，观察到单斜相和正交相共存。所有合成的正半导体材料在 HClO4 的酸性条件下都具有光电分水活性。钼含量较低（x = 0.05）的样品的光致化学活性最高，其带隙也最窄。富钼材料的整体活性降低可能与斜方体结构促进光诱导质子插入的倾向较高有关。微分电化学质谱法（DEMS）确定了这一机制。氧气（m/z 32）和过氧化氢（m/z 34）被确定为主要产物。成分变化较小的材料（x = 0.05）对催化活性和选择性有显著影响，凸显了材料设计的重要性。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Electrocatalysis CHEMISTRY, PHYSICAL-ELECTROCHEMISTRY

CiteScore

4.80

自引率

6.50%

发文量

审稿时长

>12 weeks

期刊介绍： Electrocatalysis is cross-disciplinary in nature, and attracts the interest of chemists, physicists, biochemists, surface and materials scientists, and engineers. Electrocatalysis provides the unique international forum solely dedicated to the exchange of novel ideas in electrocatalysis for academic, government, and industrial researchers. Quick publication of new results, concepts, and inventions made involving Electrocatalysis stimulates scientific discoveries and breakthroughs, promotes the scientific and engineering concepts that are critical to the development of novel electrochemical technologies. Electrocatalysis publishes original submissions in the form of letters, research papers, review articles, book reviews, and educational papers. Letters are preliminary reports that communicate new and important findings. Regular research papers are complete reports of new results, and their analysis and discussion. Review articles critically and constructively examine development in areas of electrocatalysis that are of broad interest and importance. Educational papers discuss important concepts whose understanding is vital to advances in theoretical and experimental aspects of electrochemical reactions.