TY - JOUR

T1 - Challenges of Mechanochemistry

T2 - Is In Situ Real-Time Quantitative Phase Analysis Always Reliable? A Case Study of Organic Salt Formation

AU - Michalchuk, Adam A.L.

AU - Tumanov, Ivan A.

AU - Konar, Sumit

AU - Kimber, Simon A.J.

AU - Pulham, Colin R.

AU - Boldyreva, Elena V.

N1 - Publisher Copyright: © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

PY - 2017/9/1

Y1 - 2017/9/1

N2 - Mechanochemical methods offer unprecedented academic and industrial opportunities for solvent-free synthesis of novel materials. The need to study mechanochemical mechanisms is growing, and has led to the development of real-time in situ X-ray powder diffraction techniques (RI-XRPD). However, despite the power of RI-XRPD methods, there remain immense challenges. In the present contribution, many of these challenges are highlighted, and their effect on the interpretation of RI-XRPD data considered. A novel data processing technique is introduced for RI-XRPD, through which the solvent-free mechanochemical synthesis of an organic salt is followed as a case study. These are compared to ex situ studies, where notable differences are observed. The process is monitored over a range of milling frequencies, and a nonlinear correlation between milling parameters and reaction rate is observed. Kinetic analysis of RI-XRPD allows, for the first time, observation of a mechanistic shift over the course of mechanical treatment, resulting from time evolving conditions within the mechanoreactor.

AB - Mechanochemical methods offer unprecedented academic and industrial opportunities for solvent-free synthesis of novel materials. The need to study mechanochemical mechanisms is growing, and has led to the development of real-time in situ X-ray powder diffraction techniques (RI-XRPD). However, despite the power of RI-XRPD methods, there remain immense challenges. In the present contribution, many of these challenges are highlighted, and their effect on the interpretation of RI-XRPD data considered. A novel data processing technique is introduced for RI-XRPD, through which the solvent-free mechanochemical synthesis of an organic salt is followed as a case study. These are compared to ex situ studies, where notable differences are observed. The process is monitored over a range of milling frequencies, and a nonlinear correlation between milling parameters and reaction rate is observed. Kinetic analysis of RI-XRPD allows, for the first time, observation of a mechanistic shift over the course of mechanical treatment, resulting from time evolving conditions within the mechanoreactor.

KW - kinetics

KW - mechanochemistry

KW - organic salts

KW - X-ray powder diffraction

KW - ACTIVATION

KW - ACID

KW - X-RAY-DIFFRACTION

KW - OPPORTUNITIES

UR - http://www.scopus.com/inward/record.url?scp=85019110441&partnerID=8YFLogxK

U2 - 10.1002/advs.201700132

DO - 10.1002/advs.201700132

M3 - Article

C2 - 28932677

AN - SCOPUS:85019110441

VL - 4

SP - 1700132

JO - Advanced Science

JF - Advanced Science

SN - 2198-3844

IS - 9

M1 - 1700132

ER -