Co(Ⅲ) doped-CoFe layered double hydroxide growth with graphene oxide as cataluminescence catalyst for detection of carbon monoxide

Highlights

• The hybridization parameters were studied to obtain Co(Ⅲ) doped CoFe LDH/GO.

• Co(Ⅲ) doped CoFe LDH/GO was first used as the sensing material in CTL.

• The sensor shows wide linear range, low LOD to detect carbon monoxide.

• The sensor was applied for detecting carbon monoxide in automobile exhaust.

Abstract

In this work, the hybridization of Co(Ⅲ) doped-CoFe layered double hydroxide and graphene oxide (CoFe LDH/GO) was first employed as catalyst to establish a cataluminescence (CTL) gas sensor for detection of carbon monoxide. In order to obtain Co(Ⅲ) doped-CoFe LDH/GO with the best CTL performance, synthesis reaction parameters including amount of oxidant, oxidation time and amount of GO were studied. The structure and morphology of Co(Ⅲ) doped-CoFe LDH/GO were characterized. The Co(Ш) doped-CoFe LDH/GO based CTL sensor enabled the selective determination of carbon monoxide with signal response of 0.5 s and restores of 1.0 s. The RSD was 5.6% and CTL intensity remained stable within 10 days. The calibration curve of carbon monoxide is linear in concentration range of 0.01–20 mg/L and the limit of detection(LOD）is 0.002 mg/L. Comparing with the reported CTL sensor, the Co(Ш) doped-CoFe LDH/GO based CTL sensor shows wide linear range, low LOD and use little assistive technology. Carbon monoxide in automobile exhaust was quantified with recoveries of 92.0% to 108.0%. The analytical results were agreed well with gas chromatography method. This work designed high performance catalytic materials for CTL detection of carbon monoxide.

Introduction

Monitoring noxious gas is very significant for public health and environmental pollution. Carbon monoxide is one of the serious air pollutants that have a significant effect on human health [1], [2]. Carbon monoxide has ability to bind hemoglobin, leading to reduce the carrying oxygen capacity of hemoglobin. That is the main cause of carbon monoxide poisoning humans [3], [4]. It's been reported that chronic exposure to air pollutants (such as carbon monoxide) delays the recovery of patients of COVID-19 and leads to severer [5]. Carbon monoxide is undetectable to humans because it is a colorless and odorless gas [6]. Therefore, it is vital to develop an effective method to detect carbon monoxide.

The traditional method of detecting carbon monoxide is gas chromatography [7], [8], which is accurate and reliable, but expensive, complicated and time-consuming. Then researchers designed a variety of economical, convenient and timesaving sensor to sensor carbon monoxide. Chemoreceptive semiconducting or catalytic combustion types of carbon monoxide sensor are the most potential candidates due to high sensitivity, fast response/recovery time, simple electronic interface [9], [10]. Table S1 summarizes carbon monoxide sensing properties of metal oxide semiconductors and catalytic combustion types of CO sensor. It can be seen from Table S1 that the response time of carbon monoxide sensors is between6 s and 3 min, and most of them have no recovery time. R-Pt/SnO₂ based sensor with response and recovery time of 6 s and 66 s [11]. The performance of carbon monoxide sensors needs to be improved. Cataluminescence (CTL) is a special chemiluminescence (CL), occurring in the catalytic oxidation of gas molecules on solid catalyst [12]. In the virtue of economy [13], straightforward operation [14], long-term stability [15], rapid responses [16], CTL are increasingly being uesd in carbon monoxide detection. For example, Na’s group firstly reported that CTL generated from the oxidation of carbon monoxide at room temperature [17]. Lv’s group developed a photocatalysis enhanced CTL sensor for detecting carbon monoxide gases [18], [19], [20], Zhou’s group developed a CTL sensor based on nano-Au/Nd₂O₃-Ca₃Nd₂O₆ for detecting carbon monoxide [21]. This implies CTL can be used to detect carbon monoxide rapidly and sensitively. The development of CTL sensor for detecting carbon monoxide is still a stimulating challenge.

Catalyst is one of the most vital parts in CTL sensing system. For example, layered rare-earth hydroxides showed a superior selectivity toward ethyl ether than Y₂O₃ [22], mesoporous TiO₂ nanoparticles for the detection of diethyl ether [23], Tb doped-La₂O₂CO₃ for the detection of amine vapors [24]. The exploitation of catalytic materials methodologies could enhance CTL performance like selectivity and sensitivity.

Layered double hydroxide (LDH) is a kind of anionic clays with the structure based on brucite (Mg(OH)₂)^- layers of which some the divalent cations have been replaced by trivalent cations yielding positively charged sheets [25], [26], [27]. The anion-exchange ability of LDHs has been utilized to create materials for application in catalysis [28], medicine delivery [29], and environmental remediation [30]. In the field of catalysis, iron-based LDH catches the eye of researchers because of its high catalytic activity. Fe(Ⅲ)-based LDH may cause the local electron transfer effect. The conductivity of materials is improved as well. Thus enhance the catalytic activity of LDH [31], [32]. Meanwhile, cobalt-containing oxides such as Co₃O₄ showed outstanding catalytic performance for carbon monoxide [33], and Co(Ⅲ) has been proved to be the active center for catalysis of carbon monoxide [34]. Therefore, Co(Ⅲ) doped-LDH assisted CTL system could be utilized to detect carbon monoxide. Further, the introduction of graphene oxide (GO) could improve the catalytic performance and absorbability of catalyzer [35]. The absorbability of catalyzer could improve analytical performance of CTL sensor [36], [37]. Hence, Co(Ⅲ) doped-CoFe LDH/GO assist CTL sensor may show excellent performance for detecting carbon monoxide.

In this work, a CTL sensor with Co(Ⅲ) doped-CoFe LDH/GO as catalyst for detection of carbon monoxide was developed. Firstly, reaction parameters of Co(Ⅲ) doped-CoFe LDH/GO synthesis including amount of oxidant, oxidation time and amount of GO were systematically studied to design CoFe LDH/GO. The structure and morphology of CoFe LDH/GO were characterized by SEM, TEM and XRD. Based on Co(Ⅲ) doped-CoFe LDH/GO, we established a selective, rapid response, rapid restore, repeatable and stable CTL sensor, which has promising application in monitoring for carbon monoxide. We investigated the practical feasibility of CTL sensor for detecting carbon monoxide in automobile exhaust. The Co(Ⅲ) doped-CoFe LDH/GO based CTL sensor possesses great potential for fast detection of carbon monoxide.