Abstract The replacement of Pt based catalysts for HER is still being a bottleneck and efforts have been made for finding new catalysts and here Rhenium nanoparticles (NPs) with the backing of bio-molecule deoxyribonucleic acid (DNA) was prepared as stable solutions. Depending upon the variation in the concentrations of DNA, two stable solutions namely, Re@DNA (0.055 M) and (0.083 M) were prepared. The formed Re NPs were in ultra-lesser size of 5 nm and with chain-like entities. The Re@DNA was stable as solution and directly drop-casted for electrochemical HER studies in 0.5 M H2SO4. The exploitation of DNA here as a scaffold avoids external binders and itself acted as a binder in HER studies. The HER studies revealed that for reaching 10 mA cm−2 current density, Re@DNA (0.055 M) showed lesser overpotential of 228 mV with a Tafel slope value of 137 mV/dec. Cycling study showed the activation of catalysts that is evidenced from the calculated ECSA from the post HER Cdl studies. Moreover, the overpotential required at 10 mA cm−2 was reduced to 152 mV which indicates high active nature of the Re@DNA. The post HER study revealed the stable nature of chain like structures of Re@DNA along with exposed sites after continuous cathodization.

中文翻译：

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使用带有铼电催化剂的 DNA 支架来增强 HER 活性

摘要 用于 HER 的铂基催化剂的替代仍然是一个瓶颈，人们一直在努力寻找新的催化剂，这里以生物分子脱氧核糖核酸 (DNA) 为支持的铼纳米粒子 (NPs) 被制备为稳定的溶液。根据 DNA 浓度的变化，制备了两种稳定的溶液，即 Re@DNA (0.055 M) 和 (0.083 M)。形成的 Re NPs 具有 5 nm 的超小尺寸和链状实体。Re@DNA 作为溶液是稳定的，直接滴铸用于 0.5 M H2SO4 中的电化学 HER 研究。此处利用 DNA 作为支架避免了外部结合剂，其本身在 HER 研究中充当结合剂。HER 研究表明，为了达到 10 mA cm−2 的电流密度，Re@DNA (0. 055 M) 显示较小的过电位，为 228 mV，Tafel 斜率为 137 mV/dec。循环研究显示了催化剂的活化，这可以从 HER Cdl 研究后计算出的 ECSA 中得到证实。此外，10 mA cm-2 所需的过电位降低到 152 mV，这表明 Re@DNA 具有高活性。HER 后研究揭示了 Re@DNA 的链状结构以及连续阴极化后暴露位点的稳定性。