ORIGINAL RESEARCH Toxic CO detection by Li-encapsulated fullerene-like BeO Javad Beheshtian 1 & Isa Ravaei 1 Received: 7 June 2017 /Accepted: 2 August 2017 # Springer Science+Business Media, LLC 2017 Abstract We report adsorption energies, structures, ener- gy gap (E g ), charge transfer, and electronic properties of carbon monoxide (CO) on primary, cation Li-, Li-, and two Li-encapsulated fullerene-like beryllium oxide (Be 16 O 16 , Li + @Be 16 O 16 , Li@Be 16 O 16 , and 2Li@Be 16 O 16 , respectively) for several adsorption states. The results have been interpreted by DFT calculations. The presented evidence shows that the CO molecule is not strongly adsorbed on the fullerene-like Be 16 O 16 lead- ing to energy release of - 0.17 to - 0.4 eV while its electronic properties did not show significant change. Li + @Be 16 O 16 , Li@Be 16 O 16 , and 2Li@Be 16 O 16 can ad- sorb carbon monoxide more strongly than their pristine fullerene-like Be 16 O 16 . The energy gap ( E g ) of the Li@Be 16 O 16 and 2Li@Be 16 O 16 significantly decreased from 3.51 and 2.88 to 2.98 and 2.26 eV, upon the CO adsorption corresponding to the most stable configura- tions, respectively. It was also shown that the electrical conductance of the Li@Be 16 O 16 and 2Li@Be 16 O 16 may be increased after the CO adsorption. It was found that the electronic properties of Li@Be 16 O 16 and 2Li@Be 16 O 16 are sensitive to the presence of CO molecule. Keywords CO . Sensor . Beryllium oxide . Li-encapsulated . Fullerene-like . DFT Introduction Nowadays, air pollution is threatening the life of human beings and other living things on the planet in different ways [1]. Carbon monoxide (CO) is a poisonous, color- less, odorless, and tasteless gas which is harmful to the human and is also the leading cause of air pollution. Moreover, as incomplete combustion creates toxic car- bon monoxide, gas sensor is needed to prevent CO poi- soning in homes or factories [2]. So, it is very impor- tant to develop sensitive sensors for the detection of carbon monoxide molecules. Many papers have investi- gated the adsorption of some molecules, especially car- bon monoxide (CO) on the nanostructure material sur- face and much research has focused on the development of suitable gas-sensitive material and hazardous chemi- cal removal [3, 4]. The CO adsorption on the surface of nanomaterials has attracted much theoretical and exper- imental research in recent years [5–9]. Since the discovery of the carbon nanotubes (CNTs) [10], the search for non-carbon nanostructure materials such as BN, SiC, AlN, AlP, ZnS, BP, and BeO has been started [11–18]. Also, many studies have investi- gated cage-like structures such as fullerenes and endohedral [19–22]. As an exceptional member of alkaline-earth oxides, beryllium oxide (BeO) can arise from an important co- valent component in the initially ionic Be–O bond [23]. Additionally, the energy gap (E g ) between the highest occupied molecular orbital and lowest unoccupied mo- lecular orbital is one of the important effective factors on the structural stability. It keeps its properties in the cluster of bulk, while, the E g of all structures are large [24]. Mechanical and physical properties of beryllium oxide arise of distinct bonding feature in BeO that * Javad Beheshtian J.Beheshtian@srttu.edu 1 Chemistry Department, Faculty of Sciences, Shahid Rajaee Teacher Training University, PO Box 16785-163, Tehran, Iran Struct Chem DOI 10.1007/s11224-017-1022-z