Unexpected Intrinsic Catalytic Function of Porous Boron Nitride Nanorods for Highly Efficient Peroxymonosulfate Activation in Water Treatment

Abstract

Porous boron nitride (BN) nanorods, which were synthesized via a one-stage pyrolysis, exhibited excellent catalytic performance for organics’ degradation via peroxymonosulfate (PMS) activation. The origin of the unexpected catalytic function of porous BN nanorods was proposed, in which non-radical oxidation driven by the defects on porous BN dominated the sulfamethoxazole degradation via the generation of singlet oxygen (1O2). The adsorption energy between PMS and BN was calculated via density functional theory (DFT), and the PMS activation kinetics were further investigated using an electrochemical methodology. The evolution of 1O2 was verified by electron spin resonance (ESR) and chemical scavenging experiments. The observed non-radical oxidation presented a high robustness in different water matrices, combined with a series of much less toxic intermediates. The used BN was easily regenerated by heating in air, in which the B–O bond was fully recovered. These findings provide new insights for BN as a non-metal catalyst for organics’ degradation via PMS activation, in both theoretical and practical prospects.

Local Electric Field Driving Selective Formation of High-Valent Co(IV)═O Species by Regulating Coordination Microenvironment of Co Single Atom

“…Only two broad peaks at approximately 18 and 44°, respectively, indexed to the (002) and (101) plane of the graphitic carbon, were observed in the obtained X-ray diffraction pattern for samples (Figure 1e), and no characteristic peaks of Co crystals emerged in, which was in line with the AC HADDF-STEM measurements. 26,27 Moreover, energydispersive spectroscopy (EDS) mapping images of Co−P 1 N 3 @ C suggest that the Co, N, and P elements are uniformly distributed on the entire architecture (Figure 1f). The morphologies of Co−S 1 N 3 @C and Co−N 4 @C also showed a similar rhombic dodecahedron structure (Figure S1).…”

Sulfur vacancies on MoS2 enhanced the activation of peroxymonosulfate through the co-existence of radical and non-radical pathways to degrade organic pollutants in wastewater

“…In a word, the reaction system included free radical species such as SO 4 c À , cOH and O 2 c À , and non-radical species like 1 O 2 . Among them, O 2 c À and 1 O 2 were the main reactive oxygen species, as demonstrated in formula (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13). In order to verify the source of these species, the variation in the PMS concentration before and aer the reaction was investigated, and the results are shown in Fig.…”

“…Accordingly, it has to introduce external activation factors including heat, 6 alkaline conditions, 7 and homogeneous 8,9 and heterogeneous catalysts. [3][4][5][10][11][12][13][14][15] Among them, a heterogeneous catalyst for the activation of PMS is a good strategy for repeated use, realization of radical and non-radical routes, etc. The activation of PMS by heterogeneous catalysts containing defect sites has attracted much attention in the past few years.…”

“…as shown in formulas(3)(4)(5)(6)(7)(8)(9)(10) and(3)(4)(5)(6)(7)(8)(9)(10)(11); (ii) the vacancies interacted with PMS; 43 and (iii) O 2 c À reduced Mo(VI),44 as shown in formulas (3-12):2O 2 c À + H 2 O / H 2 O 2 + OH À + 1 O 2 (3-10) O 2 c À +cOH + 2H + / OH À + 1 O 2 (3-11)Mo(VI) + O 2 c À + 2H + / Mo(IV) + 1 O 2(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) …”