发表机构
University of Dhaka（达卡大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过密度泛函理论计算发现，铂掺杂B12N12纳米笼能显著增强光气吸附并实现室温可逆检测，是最有效的策略。
AI 中文摘要
本研究使用色散校正密度泛函理论[B3LYP-D3(BJ)]，考察了光气(COCl2)在纯净及贵金属(Ag、Au、Pd、Pt)掺杂的B12N12纳米笼上的吸附。硼位点取代使HOMO-LUMO能隙的缩小程度远大于氮位点取代(69-82%对41-67%)，因此本研究全程采用硼位点取代。所有体系均经过完全优化；多种初始几何构型收敛到每个掺杂剂的两个稳定极小值，即X-O和X-Cl。纯净B12N12对光气的结合较弱(Eads = -12.8至-24.9 kJ mol^-1)。掺杂增强了结合，经平衡校正后范围为-14.0至-60.7 kJ mol^-1，其中铂表现出最高的亲和力和结构稳定性。自然布居分析表明，光气最多贡献0.33 e，而QTAIM将所有笼-吸附质键临界点归类为闭壳层或中间型，证实了物理吸附。振动频率分析确认所有结构均为真实极小值，并揭示吸附熵惩罚(59-161 J mol^-1 K^-1)具有决定性作用。在Grimme准谐振近似下，纯净笼无法结合光气(Delta G = +23.8至+27.9 kJ mol^-1)，而仅Pt-O (Delta G = -8.8 kJ mol^-1)和Pd-O (-7.2 kJ mol^-1)在298 K下能自发吸附光气。过渡态理论表明室温下快速恢复(tau = 43 ms for Pt-O)，而热力学脱附发生在69.6摄氏度，确保了实用的再生窗口。银掺杂笼提供窄的吸附后能隙和高亲电性，但无法在环境条件下保留光气。因此，铂掺杂是利用B12N12纳米笼进行可逆光气检测的最有效策略。
英文摘要
This study examines phosgene (COCl2) adsorption on pristine and noble metal-doped (Ag, Au, Pd, Pt) B12N12 nanocages using dispersion-corrected density functional theory [B3LYP-D3(BJ)]. Boron-site substitution narrows the HOMO-LUMO gap far more than nitrogen-site substitution (69-82% vs 41-67%) and was adopted throughout. All systems were fully optimized; multiple starting geometries converged to two stable minima per dopant, X-O and X-Cl. Pristine B12N12 binds phosgene weakly (Eads = -12.8 to -24.9 kJ mol^-1). Doping strengthens binding, spanning -14.0 to -60.7 kJ mol^-1 after counterpoise correction, with platinum exhibiting the highest affinity and structural stability. Natural population analysis indicates phosgene donates at most 0.33 e, and QTAIM classifies all cage-adsorbate bond critical points as closed-shell or intermediate, confirming physisorption. Vibrational frequency analysis confirms all structures as true minima and reveals that the adsorption entropy penalty (59-161 J mol^-1 K^-1) is decisive. Under Grimme's quasi-harmonic approximation, pristine cages fail to bind phosgene (Delta G = +23.8 to +27.9 kJ mol^-1), whereas only Pt-O (Delta G = -8.8 kJ mol^-1) and Pd-O (-7.2 kJ mol^-1) adsorb phosgene spontaneously at 298 K. Transition-state theory indicates rapid room-temperature recovery (tau = 43 ms for Pt-O), while thermodynamic desorption occurs at 69.6 deg C, ensuring a practical regeneration window. Silver-doped cages provide narrow post-adsorption gaps and high electrophilicity but cannot retain phosgene at ambient conditions. Platinum doping is therefore the most effective strategy for reversible phosgene detection using B12N12 nanocages.
CommentsKeywords: Density functional theory, B12N12 nanocages, Transition metal doping, Phosgene gas sensing, Adsorption
