NH₄⁺ Charge Carrier Coordinated H‐Bonded Organic Small Molecule for Fast and Superstable Rechargeable Zinc Batteries

Abstract

Organic small molecules as high‐capacity cathodes for Zn‐organic batteries have inspired numerous interests, but are trapped by their easy‐dissolution in electrolytes. Here we knit ultrastable lock‐and‐key hydrogen‐bonding networks between 2, 7‐dinitropyrene‐4, 5, 9, 10‐tetraone (DNPT) and NH4+ charge carrier. DNPT with octuple‐active carbonyl/nitro centers (H‐bond acceptor) are redox‐exclusively accessible for flexible tetrahedral NH4+ ions (H‐bond donator) but exclude larger and rigid Zn2+, due to a lower activation energy (0.14 vs. 0.31 eV). NH4+ coordinated H‐bonding chemistry conquers the stability barrier of DNPT in electrolyte, and gives fast diffusion kinetics of non‐metallic charge carrier. A stable two‐step 4e− NH4+ coordination with DNPT cathode harvests a high capacity (320 mAh g−1), a high‐rate capability (50 A g−1) and an ultralong life (60,000 cycles). This finding points to a new paradigm for H‐bond stabilized organic small molecules to design advanced zinc batteries.

Fabricating N, P-Codoped Hierarchical Porous Carbons from Lignin via Assembled Templating and Activation Strategy for High-Performance Supercapacitors

“…The charge storage mechanism contributed by the capacitive and diffusion-controlled processes within the NP-HPLC-0.75 electrode was investigated. By observing the power-law relationship i = kv b between peak current ( i ) and scan rate ( v ), a power exponent b ranging from 0.5 to 1 can be obtained. , As depicted in Figure S9, both reduction and oxidation peaks of the NP-HPLC-0.75 electrode exhibit a b value of 0.90, indicating a rapid surface-governed process . Dunn’s method ( i v = k 1 v + k 2 v 1/2 ) was further used to investigate the energy storage mechanism of the NP-HPLC-0.75 electrode, where the total current ( i v ) of the CV curve comprises both capacitive-controlled current ( k 1 v ) and diffusion-controlled current ( k 2 v 1/2 ) .…”

Nitrogen-Doped Hierarchical Nanoporous Carbon Materials from Discarded Polyurethane Sponges via One-Step Double-Activation Method for Double-Layer Capacitors

“…In our investigation, both NPC-Z and NPC-CZ demonstrated b values close to 1 (NPC-Z: 0.96; NPC-CZ: 0.95) in Figure c, indicating predominantly surface-dominated capacitive responses and slight diffusion-controlled processes. The capacitive contribution of NPC-Z and NPC-CZ electrodes was further investigated using Dunn’s technique: i = k 1 v + k 2 v 1/2 , , where k 1 and k 2 represent constants, k 1 v and k 2 v 1/2 are the current density contributed from fast capacitive process and diffusion-controlled process, respectively. The surface-controlled capacitive contribution accounts for a significant portion, reaching 89.3% for NPC-Z in Figure S4b and 89.9% for NPC-CZ in Figure d at 50 mV s –1 .…”

Carbonyl Chemistry for Advanced Electrochemical Energy Storage Systems

“…Notably, introducing the special substance into the electrolyte can also stabilize the organic small molecule. − For example, the tetrahedral NH 4 + charge carrier has been employed to link with 2,7-dinitropyrene-4,5,9,10-tetraone (DNPT) for constructing hydrogen-bonding networks. High-density redox-active motifs of DNPT and high-kinetics NH 4 + coordination contribute to a stable two-step four-electron charge storage process, affording the DNPT cathode with a high capacity (320 mAh g –1 ), a high rate capability (50 A g –1 ), and an ultralong life (60000 cycles) …”